[House Hearing, 111 Congress]
[From the U.S. Government Publishing Office]
MITIGATING THE IMPACT OF
VOLCANIC ASH CLOUDS ON AVIATION:
WHAT DO WE NEED TO KNOW?
=======================================================================
HEARING
BEFORE THE
SUBCOMMITTEE ON SPACE AND AERONAUTICS
COMMITTEE ON SCIENCE AND TECHNOLOGY
HOUSE OF REPRESENTATIVES
ONE HUNDRED ELEVENTH CONGRESS
SECOND SESSION
__________
MAY 5, 2010
__________
Serial No. 111-93
__________
Printed for the use of the Committee on Science and Technology
Available via the World Wide Web: http://www.science.house.gov
______
U.S. GOVERNMENT PRINTING OFFICE
*61-778 WASHINGTON : 2010
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COMMITTEE ON SCIENCE AND TECHNOLOGY
HON. BART GORDON, Tennessee, Chair
JERRY F. COSTELLO, Illinois RALPH M. HALL, Texas
EDDIE BERNICE JOHNSON, Texas F. JAMES SENSENBRENNER JR.,
LYNN C. WOOLSEY, California Wisconsin
DAVID WU, Oregon LAMAR S. SMITH, Texas
BRIAN BAIRD, Washington DANA ROHRABACHER, California
BRAD MILLER, North Carolina ROSCOE G. BARTLETT, Maryland
DANIEL LIPINSKI, Illinois VERNON J. EHLERS, Michigan
GABRIELLE GIFFORDS, Arizona FRANK D. LUCAS, Oklahoma
DONNA F. EDWARDS, Maryland JUDY BIGGERT, Illinois
MARCIA L. FUDGE, Ohio W. TODD AKIN, Missouri
BEN R. LUJAN, New Mexico RANDY NEUGEBAUER, Texas
PAUL D. TONKO, New York BOB INGLIS, South Carolina
STEVEN R. ROTHMAN, New Jersey MICHAEL T. McCAUL, Texas
JIM MATHESON, Utah MARIO DIAZ-BALART, Florida
LINCOLN DAVIS, Tennessee BRIAN P. BILBRAY, California
BEN CHANDLER, Kentucky ADRIAN SMITH, Nebraska
RUSS CARNAHAN, Missouri PAUL C. BROUN, Georgia
BARON P. HILL, Indiana PETE OLSON, Texas
HARRY E. MITCHELL, Arizona
CHARLES A. WILSON, Ohio
KATHLEEN DAHLKEMPER, Pennsylvania
ALAN GRAYSON, Florida
SUZANNE M. KOSMAS, Florida
GARY C. PETERS, Michigan
JOHN GARAMENDI, California
VACANCY
------
Subcommittee on Space and Aeronautics
HON. GABRIELLE GIFFORDS, Arizona, Chair
DAVID WU, Oregon PETE OLSON, Texas
DONNA F. EDWARDS, Maryland F. JAMES SENSENBRENNER JR.,
MARCIA L. FUDGE, Ohio Wisconsin
PARKER GRIFFITH, Alabama DANA ROHRABACHER, California
STEVEN R. ROTHMAN, New Jersey FRANK D. LUCAS, Oklahoma
BARON P. HILL, Indiana MICHAEL T. McCAUL, Texas
CHARLES A. WILSON, Ohio
ALAN GRAYSON, Florida
SUZANNE M. KOSMAS, Florida
BART GORDON, Tennessee RALPH M. HALL, Texas
RICHARD OBERMANN Subcommittee Staff Director
PAM WHITNEY Democratic Professional Staff Member
ALLEN LI Democratic Professional Staff Member
KEN MONROE Republican Professional Staff Member
ED FEDDEMAN Republican Professional Staff Member
DEVIN BRYANT Research Assistant
C O N T E N T S
May 5, 2010
Page
Witness List..................................................... 2
Hearing Charter.................................................. 3
Opening Statements
Statement by Representative Gabrielle Giffords, Chairwoman,
Subcommittee on Space and Aeronautics, Committee on Science and
Technology, U.S. House of Representatives...................... 10
Written Statement............................................ 11
Statement by Representative Pete Olson, Ranking Minority Member,
Subcommittee on Space and Aeronautics, Committee on Science and
Technology, U.S. House of Representatives...................... 12
Written Statement............................................ 12
Witnesses:
Dr. Tony Strazisar, Senior Technical Advisor, Aeronautics
Research Mission Directorate, National Aeronautics and Space
Administration
Oral Statement............................................... 13
Written Statement............................................ 15
Dr. Jack A. Kaye, Earth Science Division, National Aeronautics
and Space Administration
Oral Statement............................................... 19
Written Statement............................................ 21
Ms. Victoria Cox, Senior Vice President, Nextgen and Operations
Planning, Air Traffic Organization, Federal Aviation
Administration
Oral Statement............................................... 26
Written Statement............................................ 27
Captain Linda M. Orlady, Executive Air Safety Vice Chair, Air
Line Pilots Association, International
Oral Statement............................................... 30
Written Statement............................................ 31
Mr. Roger Dinius, Flight Safety Director, GE Aviation
Oral Statement............................................... 35
Written Statement............................................ 36
Discussion
Characterizing the Risk........................................ 39
The European Response.......................................... 40
Coordinating Research Among Agencies........................... 41
The Use of Simulations for Training............................ 42
Engine Design.................................................. 43
European Consultations......................................... 45
Detecting Contaminants......................................... 45
Human Factor................................................... 46
NASA DC-8 Experience........................................... 46
Detection Systems.............................................. 48
Future Remote Sensing.......................................... 49
Priorities..................................................... 50
Appendix: Answers to Post-Hearing Questions
Dr. Tony Strazisar, Senior Technical Advisor, Aeronautics
Research Mission Directorate, National Aeronautics and Space
Administration................................................. 54
Dr. Jack A. Kaye, Earth Science Division, National Aeronautics
and Space Administration....................................... 57
Ms. Victoria Cox, Senior Vice President, Nextgen and Operations
Planning, Air Traffic Organization, Federal Aviation
Administration................................................. 59
Captain Linda M. Orlady, Executive Air Safety Vice Chair, Air
Line Pilots Association, International......................... 61
Mr. Roger Dinius, Flight Safety Director, GE Aviation............ 63
MITIGATING THE IMPACT OF VOLCANIC ASH CLOUDS ON AVIATION: WHAT DO WE
NEED TO KNOW?
----------
WEDNESDAY, MAY 5, 2010
House of Representatives,
Subcommittee on Space and Aeronautics,
Committee on Science and Technology,
Washington, DC.
The Subcommittee met, pursuant to call, at 10:10 a.m., in
Room 2318 of the Rayburn House Office Building, Hon. Gabrielle
Giffords [Chairwoman of the Subcommittee] presiding.
hearing charter
U.S. HOUSE OF REPRESENTATIVES
COMMITTEE ON SCIENCE AND TECHNOLOGY
SUBCOMMITTEE ON SPACE AND AERONAUTICS
Mitigating the Impact of Volcanic
Ash Clouds on Aviation-
What Do We Need to Know?
may 5, 2010
10 a.m.-12 p.m.
2318 rayburn house office building
I. Purpose
On May 5, 2010 the Subcommittee on Space and Aeronautics will hold
a hearing on the research needed to improve our understanding of the
impact of volcanic ash clouds on aircraft and aircraft operations and
what can be done to mitigate that impact. Last year, when the Mount
Redoubt volcano erupted southwest of Anchorage, one of the operating
airlines grounded its fleet, diverted flights and wrapped the engines
of its parked planes in plastic sealant. Most recently, the eruption of
Iceland's Eyjafjallajokull volcano paralyzed air travel in Europe for
six days, is reported to have inconvenienced hundreds of thousands of
passengers around the world, and is projected to cause airline revenue
losses of at least $1.7 billion. At this hearing, the Subcommittee will
examine the role Federal research can play in:
Characterizing the damage volcanic ash causes to
aircraft and aircraft engines;
Devising ways to minimize the negative effects of
volcanic ash on aircraft and aircraft systems such as engines;
Improving the modeling, detection, and prediction of
how volcanic ash clouds propagate and dissipate, particularly
through the integrated use of civil space-based assets;
Informing guidelines and regulations that establish
what aircraft should do when encountering volcanic ash clouds
and when it is safe to fly in airspace contaminated with
volcanic ash; and
Improving air traffic management procedures,
capabilities and features, including those planned for the new
NextGen air traffic control system, to efficiently circumvent
contaminated airspace.
II. Planned Witnesses:
Dr. Tony Strazisar
Senior Technical Advisor
Aeronautics Research Mission Directorate
National Aeronautics and Space Administration
[Substituting for Associate Administrator Jaiwon Shin]
Dr. Jack A. Kaye
Earth Science Division
National Aeronautics and Space Administration
Ms. Victoria Cox
Senior VP, NextGen and Operations Planning
Air Traffic Organization
Federal Aviation Administration
Captain Linda M. Orlady
Executive Air Safety Vice Chair
Air Line Pilots Association, International
Mr. Roger Dinius
Flight Safety Director
GE Aviation
III. Overview
Following the biggest disruption in air travel since September 11,
2001, there is much discussion in Europe about the response to the
volcanic ash cloud emergency created by the Eyjafjallajokull volcano.
Some of the discussion focuses on whether the closure of European
airspace and its duration were necessary in the first place. The
controversy in Europe over the United Kingdom's Civil Aviation
Authority's (CAA) decision to close British airspace and the
authority's subsequent permission to allow resumption of flights in
specified areas highlights the challenge aviation regulators face in
light of insufficient scientific data to establish (1) the volcanic ash
contaminant level below which air travel is safe and permissible; (2)
the atmospheric location and concentrations of ash such that safe
flying corridors can be determined on a real-time basis; and (3) the
damage, both immediate and long-term, that volcanic ash inflicts on
aircraft, particularly their engines.
Although the disruption caused by the Icelandic volcano is not the
first time air travel has been impacted by volcanic ash, the magnitude
of the disruption is the greatest experienced to date. Anecdotal
evidence from several incidents where aircraft have previously
encountered volcanic ash alerted aviation regulatory bodies on the
dangers of flying through such conditions. Several near-catastrophic
incidents involving volcanic ash have occurred:
In 1982, after flying through an ash cloud, a British
Airways Boeing 747 near Jakarta, Indonesia lost all four of its
engines as they choked on the ash and flamed out. Ash was
reported to have filled the cabin through air vents and the
cockpit window was severely scratched. Subsequently, the pilots
were able to restart three of the four engines and land safely
in Jakarta.
In 1982, one month after the British Airways
incident, a Singapore Airlines Boeing 747 lost two of its four
engines and was forced to land in Jakarta because of an ash
encounter.
In 1989, a KLM Royal Dutch Airlines Boeing 747
encountered an ash cloud caused by Mount Redoubt while
descending into Anchorage International Airport. The aircraft
lost all four engines and about half of its instruments failed.
Pilots were able to restart all four engines and landed safely.
In response to these incidents, and because there were no agreed
upon values of ash concentration that constitute a hazard to aircraft
engines, the International Civil Aviation Organization (ICAO), a U.N.
agency, recommended avoidance of volcanic ash clouds as the preferred
course of action. ICAO also created a worldwide monitoring system
composed of 9 Volcanic Ash Advisory Centers (VAAC). The Washington VAAC
and Anchorage VAAC are operated by the National Oceanic and Atmospheric
Administration (NOAA). [Attachment I shows the VAACs and their areas of
responsibility]. According to the Federal Aviation Administration
(FAA), the problem of ash clouds in the United States generally occurs
in Alaska, Hawaii or the Pacific Northwest. In addition, in part to
address the hazard posed by airborne volcanic ash in the North Pacific,
the U.S. Geological Survey (USGS), in cooperation with the University
of Alaska Fairbanks Geophysical Institute and the Alaska Division of
Geological and Geophysical Surveys, established the Alaska Volcano
Observatory (AVO) with offices in Anchorage and Fairbanks. The AVO
provides hazard assessments, updates and warnings of volcanic activity
in Alaska.
NASA has first-hand knowledge of the effects of flying through
volcanic ash clouds and the delayed effect on jet engine performance.
When its scientists were flying in a DC-8 research aircraft en route to
Sweden in February 2000, they flew for about 8 minutes through an ash
cloud, a fact unknown to the pilots until they were alerted by on-board
scientists who had noticed the event using special instrumentation;
conventional radar equipment is incapable of discerning volcanic ash
clouds. Although the pilots saw no change in performance in the
aircraft, either immediately after being told of the encounter or even
after 60 hours of flying in Sweden, a borescopic inspection was
performed on all four engines following the aircraft's return to the
U.S. Results of the analysis caused NASA to send one of the engines for
an overhaul. The agency found that ash clogged holes that provide bleed
air cooling to turbine blades, and also left deposits on the turbine
blades after ash entered the combustion chamber and melted. [See
pictures of damage to one of the engines in Attachment II] The
maintenance factory told NASA that they had substantially decreased the
life of the engines and that they would have noticed a degradation in
performance in as little as a hundred flight hours because of
overheating of the engine fan blades. All four engines were
subsequently overhauled. Dr. Jaiwon Shin, a witness at the hearing, can
provide details on NASA's related aeronautics research activities. He
will be accompanied by Mr. Thomas Grindle who is familiar with the
events associated with the February 2000 flight.
NASA does not have operational responsibility for observation and
analysis of volcanic gas and aerosol emissions. However, its fleet of
research spacecraft provides data that are directly applicable to
understanding the hazards presented by these phenomena. According to
NASA, in response to the recent European situation, it is providing
near-real-time information on volcanic sulfur dioxide and ash aerosols
from the Ozone Monitoring Instrument aboard the Aura satellite for the
VAACs in London and Toulouse, in collaboration with NOAA. NASA states
that the information provided to the London and Toulouse VAACs had been
previously available for sectors covering the Americas and the Pacific
(in collaboration with the Anchorage and Washington VAACs). Numerous
other NASA spacecraft instruments provide important data relevant to
the problem of volcanic ash clouds. One example is data recently
acquired by the Multiangle Imaging SpectroRadiometer instrument on the
Terra spacecraft that provide not only the horizontal extent of the
plume over Iceland but detailed information about its vertical extent
as well. In addition to providing measurements and information to aid
decision-makers in responding to the volcanic event and its aftermath,
these data from NASA's research satellites are being utilized in
several ongoing NASA-sponsored scientific studies of solid Earth
processes, atmospheric composition and air quality, Earth's radiation
balance and aviation forecasting improvement methodologies within
NASA's Earth Science Division's Research and Analysis (R&A) and Applied
Sciences programs. Dr. Jack Kaye, a witness at the hearing, can provide
additional details on the capabilities of NASA's Earth observation
satellites.
The Airline Pilots Association (ALPA), the largest airline pilot
union in the world, representing nearly 53,000 pilots at 38 U.S. and
Canadian airlines, has devoted several years to expanding the database
of operationally relevant information on the potential hazard caused by
volcanic ash and improving the warning system necessary to reduce
unplanned encounters with hazardous ash clouds. ALPA believes its
information may be useful towards understanding the hazard;
understanding recommended practices for avoidance, if possible;
achieving survival in the event of an unexpected encounter; and
finally, reporting the experience. Regarding the recent situation in
Europe, it warned members to identify alternate routes to avoid ash
clouds. Captain Linda Orlady, a witness at the hearing, can provide
additional details on ALPA's relevant activities.
When the ban over air travel was lifted in Europe, officials broke
the affected areas of airspace into three tiers: normal flight zones
where ash no longer poses a risk, no-fly zones where ash remains in
high concentrations, and intermediate, potentially hazardous zones
where flights can proceed with caution, subject to route restrictions
and other limitations. The UK Civil Aviation Authority (UK's equivalent
of the FAA) lifted flight restrictions after consulting with many
parties, including the FAA and aircraft and engine manufacturers. In a
statement, the FAA indicated its support for the decision by the
European Commission to resume air traffic in parts of continental
Europe. The FAA said, in its press release, that ``This gradual,
cautious return of operations is reliant on the track of the volcanic
ash cloud which is being monitored closely. The FAA is continuing to
work with the European Union and is sharing technical information and
guidance based on previous experience managing weather and volcanic
events that have affected portions of U.S. airspace. The FAA remains
ready to assist both the air carriers and our colleagues in Europe to
do whatever is necessary to help stranded passengers and to safely
return air service between our continents.'' In addition, the FAA
released on April 22, 2010 a Special Airworthiness Information Bulletin
(SAIB) advising ``owners and operators of aircraft equipped with
turbine engines that operate in airspace where volcanic ash may be
present, of recently issued communications from engine manufacturers.''
SAIB Number NE-10-28 recommends that:
``Before flying from the United States to Europe or within
Europe, aircraft owners and operators should review the
following recommendations:
Although the FAA does not recommend engine operation
or flight into a visible volcanic ash cloud, we do recommend
that you obtain definitive information on operational
limitations around ash clouds, if any, from each of the
European National Authority of the State(s), of which you plan
flight operations.
Follow all aircraft and engine manufacturer's
operating and maintenance instructions pertaining to operations
in airspace where volcanic ash may be near or present.
Report any inadvertent encounter with volcanic ash or
relevant findings, including abnormal engine behavior, to the
respective type certificate holders of the aircraft and
engines.''
Ms. Victoria Cox, a witness at the hearing, can provide additional
details on FAA's collaborative efforts to assist other aviation
regulators as well as how similar situations may be managed under the
NextGen air traffic control system. In addition, Mr. Roger Dinius, also
a witness at the hearing, can provide details on GE Aviation's role in
helping European aviation regulators establish conditions for flight
resumption.
There is widespread agreement on the need for a better
understanding of the effects of volcanic ash on aircraft and how
particulates propagate in the atmosphere. Of particular concern is the
small amount of research so far on the cumulative impact of flying for
extended amounts of time through even low levels of volcanic ash. What
knowledge we still lack and how we go about gaining that better
understanding--possibly through additional research, data collection
and computer modeling--will be discussed during this hearing.
IV. Issues
Aeronautics Research and Information Needs
What is known about the impact of aircraft flying
through volcanic ash clouds? What are the areas of greatest
uncertainty in our knowledge and what research is needed to
reduce that uncertainty?
What research is needed to better understand when and
under what conditions (e.g., size of particulates, ash
concentration, and height of the cloud) it is safe to fly
through airspace that has been contaminated with volcanic ash
particulates? Is there a way to characterize the risk of flying
under different conditions?
What research is needed to develop sensors and
instrumentation to warn aircraft operators of volcanic ash
conditions?
Can human factors research enhance the training of
pilots who might deal with volcanic ash conditions?
What is known about how much damage volcanic ash can
inflict on aircraft engines? What research can help engine
designers determine the extent to which the safety of aircraft
engines could be enhanced on future aircraft that inadvertently
fly through volcanic ash conditions?
What is the extent of research on the effects of
aircraft flying through volcanic ash clouds by the National
Aeronautics and Space Administration (NASA) and the Federal
Aviation Administration (FAA)? What has been learned?
What additional research is needed to help establish
limits and conditions under which it is safe to fly in
contaminated airspace? What level of resources would such
research entail?
To what extent are Federal research programs on
aircraft flying through volcanic ash coordinated and how easy
or difficult is it to share the research results with relevant
stakeholders? To what extent are U.S. and international
research programs coordinated?
Are there other sources of research (e.g. by the
commercial, or private, non-government sectors) on the effects
of aircraft flying in volcanic ash conditions?
Detection, Monitoring and Modeling Activities and Assets
What civil Federal capabilities, such as Earth-
observation satellites, are used to assist in detecting and
monitoring volcanic ash cloud propagation and dispersion? How
effective are they?
To what extent will planned Earth observing
satellites contribute to the detection, monitoring and
understanding of volcanic ash clouds and their composition?
What enhancements to space-based or airborne sensors,
technologies, or techniques are needed to further our
understanding of volcanic ash clouds and particulate
dispersion?
How effective are current modeling techniques in
forecasting the propagation of volcanic ash clouds?
How are the scientific results of research and
monitoring of volcanic ash clouds coordinated, analyzed,
filtered and disseminated to decision makers who are
responsible for determining when it is safe to fly, and what,
if any, improvements need to be made to ensure the
effectiveness of coordinating and disseminating the
information?
What is the extent of collaboration, both nationally
and internationally, in the detection and monitoring of
atmospheric volcanic ash conditions and dissemination of
warnings?
Air Traffic Management/NextGen and Voluntary Reporting Mechanisms
What air traffic regulations are currently in effect
to manage aircraft operations in the event of a volcanic ash
cloud event, such as those experienced in Alaska? Are there
contingency plans for dealing with such events? What
information is needed to establish ``safe'' flight corridors?
What was FAA's role in collaborating with
international aviation regulatory bodies to establish safe
conditions for resumption of air travel following the eruption
of the Eyjafjallajokull volcano?
Can research help inform the establishment of
airspace management and air traffic control procedures in the
event of a volcanic ash cloud situation? If so, in what areas
is research needed and who should conduct such research in the
U.S.?
Will the management of aircraft flying in volcanic
ash situations be handled differently under NextGen? What
information does NextGen need to automatically assign safer air
traffic routes? Is that information available today?
Have any of the voluntary safety reporting
mechanisms, such as the Aviation Safety Information and Sharing
(ASIAS) System, identified issues associated with aircraft
flying through volcanic ash clouds?
Chairwoman Giffords. This hearing will now come to order.
Good morning, everyone. It is with real pleasure that we
invite you today to the Subcommittee's hearing. We have an
impressive panel of experts, and I am really fortunate to have
had a chance to speak, before we started, with some of them. We
look forward to having a very good and timely discussion.
As you know, the eruption of the volcano in Iceland forced
the closure of European airspace, paralyzing air traffic travel
for 6 days. Hundreds of thousands of passengers around the
world, including many Americans, in fact, friends and family
members I think of all of us, were stranded and airline revenue
losses may end up reaching at least $1.7 billion.
While the ink has yet to dry on that episode, one thing is
certainly clear: Aviation regulators have insufficient
scientific data to establish, one, at what level of volcanic
ash contamination air travel is safe; two, where ash clouds are
and how concentrated they are on a real-time basis; and three,
the extent of damage, both immediate and long-term, that
volcanic ash inflicts on aircraft and particularly on their
engines.
Moreover, the dangers to aircraft and passengers are not
hypothetical, as our witnesses will testify. For example, in
1982, after flying through an ash cloud, a British Airways
Boeing 747 near Jakarta, Indonesia, lost all four of its
engines as they choked on the ash and flamed out. Ash was
reported to have filled the cabin through air vents and the
cockpit window was severely scratched. Also in 1982, one month
after the British Airways incident, a Singapore Airlines Boeing
747 lost two of its four engines and was forced to land in
Jakarta because of an ash encounter. In 1989, a KLM Royal Dutch
Airlines Boeing 747 encountered an ash cloud caused by Mount
Redoubt while descending into Anchorage International Airport
in Alaska. The aircraft lost all four engines and half of its
instruments failed as well.
I strongly believe that this Subcommittee should, as one of
its primary responsibilities, identify space and aeronautics
issues of concern to the Nation and encourage the development
of practical solutions if possible. Oftentimes, focused
research can help.
While we have been fortunate not to have experienced this
type of widespread volcano-induced airspace closure that Europe
just experienced, we should view this as a wake-up call for all
of us. The reality is that we do have some relevant experience
and technologies that can be brought to bear on this problem.
As you will hear later, the inadvertent encounter of a volcanic
ash cloud by a NASA research aircraft in 2000 showed how much
damage volcanic ash can inflict to aircraft engines and the
hidden nature of that damage. And NASA was recently called on
by our European friends to monitor, using its unique satellite-
based instruments, the ash plume as it made its way towards
continental Europe.
As our country's aviation regulator, FAA collaborates with
other Federal agencies to ensure that our Nation's air traffic
safely circumvents any problematic conditions, including
volcanic ash situations.
Avoiding volcanic ash clouds certainly is not as easy as it
sounds. Conventional radar cannot discern ash particulates.
Pilots are keenly aware of this and have been trained on what
to do when advised of potential problems.
Finally, as you will hear today, engine manufacturers
provided assistance during the decision-making period leading
up to the reopening of Europe's skies.
I called today's hearing so that this Subcommittee can help
determine what we know and where our knowledge is still
lacking. Most importantly, I would like to find out if any
additional research can enhance our understanding of the impact
of volcanic ash on aviation so that we can ensure that our
reaction to future situations is based on sound data and
information.
With that, I want to again welcome our witnesses.
[The prepared statement of Ms. Giffords follows:]
Prepared Statement of Chairwoman Gabrielle Giffords
Good morning, it's a pleasure to welcome you to today's
Subcommittee hearing. We have an impressive panel of experts appearing
before us this morning, and I look forward to a good discussion.
Today's hearing is timely. As you know, the eruption of the volcano
in Iceland forced the closure of European airspace, paralyzing air
travel for six days. Hundreds of thousands of passengers around the
world--including many Americans--were stranded and airline revenue
losses may reach at least $1.7 billion.
While the ink has yet to dry on that episode, one thing is clear:
Aviation regulators have insufficient scientific data to establish
(1) at what level of volcanic ash contamination air travel is safe; (2)
where ash clouds are and how concentrated they are on a real-time
basis; and (3) the extent of damage, both immediate and long-term, that
volcanic ash inflicts on aircraft and particularly on their engines.
Moreover, the dangers to aircraft and passengers are not
hypothetical--as our witnesses will testify.
For example, in 1982, after flying through an ash cloud, a British
Airways Boeing 747 near Jakarta, Indonesia lost all four of its engines
as they choked on the ash and flamed out. Ash was reported to have
filled the cabin through air vents and the cockpit window was severely
scratched.
Also in 1982--one month after the British Airways incident--a
Singapore Airlines Boeing 747 lost two of its four engines and was
forced to land in Jakarta because of an ash encounter.
In 1989, a KLM Royal Dutch Airlines Boeing 747 encountered an ash
cloud caused by Mount Redoubt while descending into Anchorage
International Airport in Alaska. The aircraft lost all four engines and
half of its instruments failed.
I strongly believe that this Subcommittee should, as one of its
primary responsibilities, identify space and aeronautics issues of
concern to the Nation and encourage the development of practical
solutions if possible. Oftentimes, focused research can help.
While we have been fortunate not to have experienced the type of
widespread volcano-induced airspace closure Europe just experienced, we
should view this as a wake-up call.
The reality is that we do have some relevant experience and
technologies that can be brought to bear on the problem.
As you will hear later, the inadvertent encounter of a volcanic ash
cloud by a NASA research aircraft in 2000 showed how much damage
volcanic ash can inflict to aircraft engines and the hidden nature of
that damage.
And NASA was recently called on by our European friends to monitor,
using its unique satellite-based instruments, the ash plume as it made
its way towards continental Europe.
As our country's aviation regulator, FAA corroborates with other
Federal agencies to ensure that our Nation's air traffic safely
circumvents any problematic conditions, including volcanic ash
situations.
Avoiding volcanic ash clouds is not as easy as it sounds.
Conventional radar cannot discern ash particulates. Pilots are keenly
aware of this and have been trained on what to do when advised of
potential conditions.
Finally, as you will hear today, engine manufacturers provided
assistance during the decision-making period leading up to the
reopening of Europe's skies.
I called today's hearing so that the Subcommittee can help
determine what we know--and where our knowledge is still lacking.
Most importantly, I would like to find out if additional research
can enhance our understanding of the impact of volcanic ash on aviation
so that we can ensure that our reaction to future situations is based
on sound data and information.
With that, I again want to welcome our witnesses, and I now will
yield to Mr. Olson for any opening remarks he would care to make.
Chairwoman Giffords. And now I yield to Mr. Olson for any
opening remarks that he would like to make.
Mr. Olson. Madam Chairwoman, thank you for calling this
morning's hearing. I greatly appreciate that.
I would like to thank our witnesses for your appearance
today. I appreciate your expertise and your willingness to
share your perspective with us on this very important issue of
how our air traffic management system can best respond to
volcanic eruptions and whether any additional research is
needed to improve safety and system performance.
The recent volcanic eruption in Iceland was a powerful
example of the interconnected world we live in today. Travelers
brace for almost anything but delays due to the eruption of an
Iceland volcano is not something many would have predicted when
they drove to the airport that day.
As a pilot myself, I am very interested to learn what we
know of the impact volcanic ash has on aircraft. I am also
eager to learn how our air traffic system weighs the known and
unknown risks associated with volcanic ash, how our system
responds when confronted with such a circumstance, and coupling
that knowledge with the desire of thousands of travelers
wanting to get to their destinations and airlines eager to get
them there.
Post 9/11, the world has been vigilant to prevent the
disruption of air travel as we saw on that day, but who could
have imagined the second biggest disruption since that day
would have been caused by a volcano in Iceland?
That leads to another topic that we need to discuss today:
What is the appropriate level of funding we should invest in
research and development on events or circumstances that would
be classified as rare or highly unlikely? It is easy to imagine
that prior to the Iceland volcano erupting, many experts would
have likely argued that funding additional research on issues
related to the impact of volcanic ash on airplanes, it would be
a low priority. Some might even say a waste of money. But
events of the previous month may now cause many to reconsider.
Are there other calamities like this that are rare but
highly disruptive that we should be researching? These
questions are difficult and frankly might be impossible to
answer but learning from this situation will help us going
forward, and for that I am pleased we are having today's
hearing.
Thank you much for coming. I yield back my time, Madam
Chairwoman.
[The prepared statement of Mr. Olson follows:]
Prepared Statement of Representative Pete Olson
Madam Chairwoman, thank you for calling this morning's hearing. I'd
like to thank our witnesses for their appearance today. I appreciate
your expertise and willingness to share your perspective with us on the
very important issue of how our air traffic management system can best
respond to volcanic eruptions and whether any additional research is
needed to improve safety and system performance.
The recent volcanic eruption in Iceland was a powerful example of
the interconnected world we live in today. Travelers brace for almost
anything, but delays due to the eruption of an Icelandic volcano is not
something many would have predicted when they drove to the airport that
day. As a pilot myself, I'm very interested to learn about what we know
of the impact volcanic ash has on aircraft. I'm also eager to learn how
our air traffic system weighs known and unknown risks associated with
volcanic ash, how our system responds when confronted with such a
circumstance, and coupling that knowledge with the desire of thousands
of travelers wanting to get to their destinations and airlines eager to
get them there.
Post 9-11, the world has been vigilant to prevent the disruption of
air travel as we saw on that day. But who could have imagined the
second biggest disruption since that day would have been caused by a
volcano in Iceland.
That leads to another topic we need to discuss here today. What is
the appropriate level of funding we should invest in research and
development on events or circumstances that would be classified as rare
or unlikely? It is easy to imagine that prior to the Iceland volcano
erupting, many experts would likely have argued that funding additional
research on issues related to the impact of volcanic ash on airplanes
would be a low priority. Events of the previous month may now cause
many to reconsider. Are there other calamities like this that are rare
but highly disruptive that we should be researching? These questions
are difficult, and frankly might be impossible to answer, but learning
from this situation will help us going forward and for that I am
pleased we are having today's hearing.
I thank you and yield back the balance of my time.
Chairwoman Giffords. Thank you, Mr. Olson.
If there are members who wish to submit additional opening
statements, your statements will be submitted for the record.
At this time I would like to introduce our witnesses. First
up, we have Dr. Tony Strazisar, who will be representing Dr.
Jaiwon Shin of NASA's Aeronautics Research Mission Directorate.
Dr. Shin unfortunately can't be here with us today but we wish
him the best. We understand that he is under the weather, but
Dr. Strazisar is a senior technical advisor for the Aeronautics
Research Mission Directorate at NASA. Welcome. We also have Dr.
Jack Kaye, who is a member of the Earth Science Division at
NASA. Good morning. Ms. Victoria Cox, who is a Senior Vice
President of NextGen and Operations Planning in Air Traffic
Organization at FAA. Good morning. Also, Captain Linda Orlady,
who is the Executive Air Safety Vice Chair of the Air Line
Pilots Association. We are very glad that you are with us this
morning, Captain. And finally we have Mr. Roger Dinius, who is
the Flight Safety Director at GE Aviation. Again, welcome.
Our witnesses should know that you will each have five
minutes for your spoken testimony. Your written testimony will
be included in the record for the hearing. When you have
completed all of your spoken testimony, we will begin with our
first round of questions, and each member will have five
minutes to ask questions. So we are going to begin this morning
with Dr. Tony Strazisar.
STATEMENT OF DR. TONY STRAZISAR, SENIOR TECHNICAL ADVISOR,
AERONAUTICS RESEARCH MISSION DIRECTORATE, NATIONAL AERONAUTICS
AND SPACE ADMINISTRATION
Mr. Strazisar. Madam Chair Giffords, Ranking Member Olson
and members of the Subcommittee, thank you for the opportunity
to appear before you today. I am here to discuss NASA's past
experiences related to the impact of volcanic ash on aircraft
systems and operations and some past and current research
activities conducted by NASA and the aviation community that
could be relevant to the issue.
The International Air Transport Association reported that
the recent eruption of Iceland's volcano cost the world's
airlines at least $1.7 billion and affected as many as 1.2
million passengers a day. Many Americans were directly or
indirectly impacted by this stoppage. Certainly there will be a
significant assessment of this issue by the global aviation
community in the coming months and years.
Detecting, monitoring and understanding volcanic ash clouds
and their composition are critical first steps in addressing
this issue, and my colleague, Jack Kaye from NASA's Science
Mission Directorate, is discussing this issue with the
subcommittee today.
Encounters with volcanic ash are known to have detrimental
effects on modern turbine engines. Particulate erosion testing
is not a part of commercial engine certification testing.
Therefore, today's engines are not certified for volcanic ash
ingestion. Engine manufacturers are currently the best source
of information regarding the impact of volcanic ash on their
engines and various conditions. To be safe, the current
established practice is to avoid flight operations in the
vicinity of known volcanic debris. As a result, volcanic ash
ingestion is not a leading cause of aircraft safety accidents
or issues. In fact, they are quite rare. There have been no
known or reported aircraft fatalities as a result of flying
through volcanic ash. Nonetheless, there are several documented
cases of aircraft experiencing engine shutdowns and/or costly
damage as a result of unintended encounters.
NASA's understanding of the effects of aircraft flying
through volcanic ash clouds comes from its evaluation of an
unplanned in-flight encounter. Early on the morning of February
28, 2000, a NASA DC-8 airplane, a highly instrumented research
platform for conducting atmospheric science research,
inadvertently flew through the fringe of a diffuse volcanic ash
cloud produced by the Mount Hekla volcano in Iceland. This
encounter lasted approximately 7 minutes and occurred in total
darkness during a ferry flight from Edwards, California, to
Kiruna, Sweden. During this flight, scientists on board the DC-
8 monitoring sensitive research instruments reported a sudden
increase in sulfur dioxide measurements that indicated the
presence of a volcanic ash cloud. Except for the reports from
the onboard science team, the DC-8 crew had no indication they
were flying through the plume from Mount Hekla. After the
airplane returned to Edwards Air Force Base, all four engines
were sent to the General Electric Strouther overhaul facility,
where they were disassembled and refurbished. Detailed engine
inspection revealed that even though this was a brief flight
through a diffuse ash cloud, the exposure was long enough and
engine temperatures were high enough that engine hot section
blades and vanes were coated and cooling air passages were
partially or completely blocked.
NASA does not have any ongoing research efforts that are
focused on the understanding of the impact of volcanic ash on
aircraft engines, mainly because the volcanic ash encounters
are very rare events and have been consistently placed at a
very low priority for research needs by the aviation community.
While NASA aeronautics research has not directly addressed
impacts of volcanic ash on aviation, it is possible that some
past and current research activities conducted by NASA and the
aviation community could be of value to industry and airspace
regulators as they seek to better understand the impact of
volcanic ash and devise strategies for addressing similar
situations in the future.
Making the best possible use of available airports and
airspace is critical to sustaining limited service during and
recovering from a major disruption such as occurred last month.
NASA-developed analysis tools can simulate air traffic
scenario, evaluate outcomes and support decisions made by air
traffic managers and airline operators.
Past research in dealing with severe weather has shown that
even the most daunting scenarios provide limited yet workable
operational solutions. Better plume measurements and
propagation forecasts and operational procedures together could
contribute to air traffic management solutions to the problem
of volcanic ash.
Since there are so many factors that contribute to the
severity of damage from volcanic ash, it is likely that even a
robust research effort will lead to engines that are tolerant
of significant amounts of ash ingestion. However, NASA research
on integrated propulsion and control systems and robust engine
control could have potential applicability in mitigating
hazards associated with volcanic ash.
Current research regarding effective interaction or
monitoring methods for the crew under degraded engine operating
conditions could be applied in instances where those
circumstances are due to volcanic ash. NASA aeronautics will
continue to make available our expertise and knowledge in these
areas to other Federal agencies and the broader aviation
community as they assess plans for national and global flight
operations in these conditions.
Thank you for your attention.
[The prepared statement of Dr. Strazisar follows:]
Prepared Statement of Tony Strazisar
Madam Chair Giffords, Ranking member Olson, and Members of the
Subcommittee, thank you for the opportunity to appear before you today.
I am here to discuss NASA's past experiences related to the impact of
volcanic ash on aircraft systems and operations, and some past and
current research activities conducted by NASA and the aviation
community which could be relevant to this issue.
Airlines thrive on reliability and predictability, as witnessed by
their published ``on-time departure'' metrics. As we have recently
learned, volcanic eruptions, and specifically, the dispersal ash clouds
are beyond today's predictive capabilities, thus upsetting the
reliability of airplane operations. In light of the great uncertainty
of the location of volcanic ash, and the extreme hazard it presents to
jet aircraft, airlines and air traffic managers take extraordinary
precautions to avoid flying into these danger zones. In the case of the
recent eruption of Iceland's Eyjafjallajokull volcano, the risk was
deemed so great that the only prudent response was to ground all
aircraft within the danger zone, which encompassed the United Kingdom
and most of northern Europe. The problems associated with the eruption
in Iceland were compounded by the fact that many of the impacted
flights were the trans-Atlantic oceanic routes, where there is no
continuous surveillance (such as radar) and the requirement for
proximity to contingency landing sites presents a significant
constraint to alternate routes.
The International Air Transport Association reported that the
volcanic eruption cost the world's airlines at least $1.7 billion and
affected as many as 1.2 million passengers a day. Many Americans were
directly or indirectly impacted by this stoppage. Certainly there will
be a significant assessment of this issue by the global aviation
community in the coming months and years.
Detecting, monitoring and understanding volcanic ash clouds and
their composition are critical first steps in addressing this issue. My
colleague, Jack Kaye, from the NASA's Science Mission Directorate is
discussing this issue with the Subcommittee at this hearing today.
Volcanic Ash and Aircraft
Encounters with volcanic ash are known to have detrimental effects
on modern turbine engines. Particulate erosion testing is a part of
some engine testing, but these tests are generally focused on abrasive
materials such as sand, which have some material properties that have a
different impact compared to volcanic ash. Therefore, today's engines
are not certified for volcanic ash ingestion.
There has been some notable research on the impact on gas turbine
engines of ingesting dust-laden air that was conducted by the Calspan
Advanced Technology Center in the late 1980s and early 1990s under
sponsorship of the Defense Nuclear Agency. The Calspan team tested
several military gas turbine engines using volcanic ash to better
understand the impacts of dust-laden air on engine operation. An
important research result is that there are a number of factors that
significantly impact the effect of a volcanic ash encounter, including
engine type, operating conditions, constituents of the ash cloud, and
ash concentrations. This research also identified several ways that ash
can damage an engine including: melting of ash on components in the
engine hot sections, erosion of components, blockage of cooling
passages in turbines, and contamination of the oil or bleed air
systems. This research also developed and validated various potential
recovery strategies for addressing in-flight operational problems,
depending upon the engine and conditions encountered.
The signs that an aircraft is in a volcanic ash condition are not
always clear. Previous ground tests of engines by Calspan indicate that
the warning signs of ash damage vary with engine type and that an ash
encounter is often very difficult to discern from existing
instrumentation until a serious problem like an engine surge or flame-
out occurs.
Engine manufacturers currently are the best source of information
regarding the impact of volcanic ash on their engines in various
conditions. The Subcommittee will be hearing directly from industry
sources about this subject at this hearing, including their experiences
recently in facilitating the resumption of commercial operations in
European airspace.
To be safe, the current established practice is to avoid flight
operations in the vicinity of known volcanic airborne debris. As a
result, volcanic ash ingestion is not a leading cause of aircraft
safety accidents or issues--in fact they are quite rare. There have
been no known or reported aircraft fatalities a result of flying
through a volcanic ash cloud. Nonetheless, there are several documented
cases of aircraft experiencing engine shutdowns and/or costly damage as
a result of an unintended encounter.
NASA DC-8 Volcanic Ash Incident
NASA's understanding of the effects of aircraft flying through
volcanic ash clouds comes from its evaluation of one unplanned in-
flight encounter. This evaluation was enabled by the presence of an
onboard science team and specialized instrumentation for unrelated
airborne chemistry research. These findings and lessons were developed
from volcanic ash plume and satellite trajectory analysis, analysis of
ash particles collected in cabin air heat exchanger filters and removed
from engines, and data from onboard instruments and engine conditions.
Early on the morning of February 28, 2000, the NASA DC-8 airplane,
a highly instrumented research platform for conducting atmospheric
science research, inadvertently flew through the fringe of a diffuse
volcanic ash cloud produced by the Mt. Hekla volcano in Iceland. This
encounter, which lasted approximately seven minutes, occurred in total
darkness (no moonlight) during a ferry flight from Edwards, California
to Kiruna, Sweden.
This particular encounter demonstrated the difficulty of predicting
the location of the ash plume produced by a volcanic eruption. Thirty
five hours after the eruption, the London Volcanic Ash Advisory Center
(VAAC), using observatory inputs, satellite pictures, radar imagery and
pilot reports, predicted the ash plume would be south of the proposed
DC-8 track. However, to provide an additional margin of safety, the DC-
8 flight path was adjusted an additional 200 miles north, with the
expectation of totally avoiding any possibility of encountering the ash
plume.
From this research mission, we have learned that a damaging
encounter with volcanic ash can be undetectable, even to an alerted
flight crew. During this flight, scientists onboard the DC-8 monitoring
sensitive research instruments reported a sudden increase in sulfur
dioxide (SO2) measurements that indicated the presence of a
volcanic ash cloud. Except for the reports from the on-board science
team, the DC-8 crew had no indication they were flying through the
plume from Mt. Hekla. In previous ash plume encounters by aircraft, the
events were frequently accompanied by an odor in the cabin air, by
changes in engine readings, by the frosting of windows, and at night,
by the presence of St. Elmo's fire on forward-facing parts of the
aircraft. NASA's DC-8 flight crew noted no change in cockpit readings,
no St. Elmo's fire, no odor or smoke, and no change in engine
instruments. They did notice that no stars were visible, but this is
typical of flight through high cirrus clouds.
Since in-flight performance checks and detailed visual inspections
after landing in Sweden revealed no damage to the airplane or engine
first-stage fan blades, the research campaign was completed, and the
airplane was ferried back to Edwards Air Force Base in California. More
complex engine borescope inspections revealed clogged cooling passages
and some heat distress in the high temperature section of the engines.
One engine appeared to be more heavily damaged.
The DC-8 is powered by four General Electric CFM56-2 high bypass
turbofan engines. All four engines were sent to the manufacturer's
General Electric Strouther overhaul facility near Arkansas City,
Kansas, where they were disassembled and refurbished. Their detailed
engine inspection revealed that even though this was a brief flight
through a diffuse ash cloud, the exposure was long enough and engine
temperatures were high enough that engine hot section blades and vanes
were coated and cooling air passages were partially or completely
blocked. All engines exhibited a fine white powder coating throughout,
leading edge erosion on high-pressure turbine vanes and blades, blocked
cooling air holes, blistered coatings, and a buildup of fine ash inside
passages. A blade with blocked cooling operates at a sufficiently
higher temperature, significantly impacting blade life. Although engine
trending did not reveal a problem, hot section parts may have begun to
fail (through blade erosion) if flown another 100 hours, in contrast to
the normal service life of thousands of hours. The engines were
overhauled, at a total cost of $3.2 million.
Research That Could Benefit Future Situations
NASA does not have any ongoing research efforts that are focused on
understanding the impact of volcanic ash on aircraft engines, mainly
because the volcanic ash encounters are very rare events and have been
consistently placed at a very low priority for research needs by the
aviation community.
While NASA aeronautics research has not directly addressed impacts
of volcanic ash on aviation, it is possible that some past and current
research activities conducted by NASA and the aviation community could
be of value to industry and airspace regulators as they seek to better
understand the impact of volcanic ash and devise strategies for
addressing similar situations in the future.
Operational procedures
Making the best possible use of available airports and airspace is
critical to sustaining limited service during, and recovering from, a
major disruption such as Eyjafjallajokull. NASA-developed analysis
tools can simulate air traffic scenarios, evaluate outcomes, and
support decisions made by air traffic managers and airline operators.
There could be some applicability of these analysis tools to decision
support tools for the oceanic flight realm, benefiting routine daily
operations as well as recovering from system disruptions such as ash
plumes.
Parallels exist between the problems presented by an ash plume and
by severe convective weather: both form in an unpredictable manner,
present a dynamically changing hazard to aviation, and require
coordinated modification of flight routes. The aviation community has
made a large, sustained investment in technology development to address
convective weather, resulting in sensors, models, and tools that have
significantly improved the ability to keep people and aircraft safely
moving when subjected to adverse weather conditions. Past research in
dealing with severe weather has shown that even the most daunting
scenarios provide limited yet workable operational solutions.
Better plume measurements and propagation forecasts and operational
procedures together could contribute to air traffic management
solutions to the problem of volcanic ash. Tracts of useable airspace
could be identified to build routes that can be used to maximize
traffic throughput in constrained airspace. Fleet management options
could be assessed to quantify the advantages and impacts of different
strategies. For example, corridors-in-the-sky that use the available
airspace could be developed and dynamically updated based on the
prevailing wind and plume conditions. Based on the traffic demands,
additional reroutes could be developed as appropriate.
Sharing information about hazards
NASA is developing new display concepts to intuitively convey new
information sets available to pilots. One such concept could improve
the current Notices to Airmen (NOTAM) system. Current NOTAMs of changes
to flight conditions are not instantaneous. Expeditious datalink of
NOTAMs with an appropriate display and notification could shorten this
to seconds to minutes of when such events occur. NOTAMs related to
volcanic ash activity are called ASHTAMs by the International Civil
Aviation Organization (ICAO), and are regularly released when such
events occur across the globe. However, such information today is very
coarse and delayed, and is therefore open to misinterpretation.
Improvements in display concepts, while not developed to specifically
address the issue of hazardous ash conditions, could enable the
provision much more detailed ash information along with real-time
updates as they become available through air traffic service providers.
NASA also has available data mining tools that might be of use to
industry and regulators to make sense of data resulting from recent
operational experiences or future tests.
Engine technologies
Since there are so many factors that contribute to the severity of
damage from volcanic ash, it is unlikely that even a robust research
effort will lead to engines that are tolerant of significant amounts of
ash ingestion. However, some NASA research in novel materials may have
an effect of mitigating some of the negative effects from ash
ingestion. For example, ceramic matrix composite turbine blades may
need fewer cooling channels which would make them less susceptible to
degraded cooling performance due to clogging. These materials may also
have better damage tolerance qualities. Similarly, research in engine
monitoring and instrumentation might also have applicability in this
circumstance.
In the 1990s, NASA conducted flight research to examine
deteriorated engine operation and performance (the Dryden Performance
Seeking Control research project). Extrapolating from that experience,
NASA research on integrated propulsion and control systems and robust
engine control (i.e. controller design and possible modification of
actuators to extend engine operating life) could have some potential
applicability in mitigating the hazards associated with volcanic ash.
Current research regarding effective interaction or monitoring methods
for the crew under degraded engine operating conditions could be
applied in instances where those circumstances are due to volcanic ash.
Conclusion
NASA Aeronautics will continue to make available our expertise and
knowledge in these areas to other Federal agencies and the broader
aviation community as they assess plans for national and global flight
operations in these conditions.
Biography for Tony Strazisar
Chairwoman Giffords. Thank you, Dr. Strazisar.
Dr. Kaye, please.
STATEMENT OF DR. JACK A. KAYE, EARTH SCIENCE DIVISION, NATIONAL
AERONAUTICS AND SPACE ADMINISTRATION
Mr. Kaye. Good morning, Chairwoman Giffords, Ranking Member
Olson and members of the Subcommittee. I appreciate having the
opportunity to appear before you today to discuss NASA's earth
science-related activities to observe and carry out scientific
research of volcanic ash clouds.
The recent eruption of Eyjafjallajokull highlights the
different types of contributions that NASA's Earth Science
program makes to the study of and response to such events.
Through its fleet of 13 major earth-observing missions, NASA is
able to rapidly generate and broadly disseminate imagery and
data products on the locations, heights and densities of ash
plumes and related hazards. These data products fuel a range of
research investigations which enhance our knowledge of solid
earth processes, atmospheric transporting composition and the
impacts that volcanic eruption have on the earth system. NASA
is also able to, and did, provide critical data streams from
these research satellites to the National Oceanic and
Atmospheric Administration to support that agency's operational
prediction of ash plumes.
Although NASA does not have operational responsibility for
observation and analysis of volcanic gas and aerosol emissions,
its fleet of research spacecraft provides data that are
directly applicable to the societal hazards presented by these
phenomena. NASA has been using its research satellites to study
volcanic eruptions, especially their atmospheric impact, for
more than 3 decades.
Several of the research satellite missions that NASA is
currently developing will be able to provide new and advanced
insights into volcanic ash cloud properties. Missions that will
be able to study the presence of aerosols in the atmosphere
include Glory, scheduled for launch later this year, NPP,
scheduled for launch in 2011, and tier 2 missions from the
decadal survey, GEO-CAPE and ACE. NPP will help to track
volcanic ash clouds using sulfur dioxide observations. Two
other decadal survey missions will also support this effort.
The DESDynI mission will improve the determination of the
likelihood of volcanic eruptions and document posteruption
changes while the HyspIRI mission will be able to detect
volcanic eruptions and determine the ash content of volcanic
plumes.
In addition to providing measurements and information to
aid decision makers in responding to the volcanic events and
its aftermath, these data from NASA's research satellites are
being utilized in several ongoing NASA-sponsored scientific
studies of solid earth processes, atmospheric composition and
air quality, earth's radiation balance and aviation forecasting
improvement methodologies within both NASA's Earth Science
Division's Research and Analysis program and its Applied
Sciences program. For example, over the past several years the
project competitively funded through the Applied Sciences
program demonstrated reliable and accurate detection of
volcanic ash clouds using observations of sulfur dioxide from
the ozone monitoring instrument on board NASA's Aura satellite.
Since volcanic eruptions are essentially the only variable
sources of SO2 large enough to be observed by
satellites, false alarms are nonexistent. Satellite
observations of sulfur dioxide thus assist operational agencies
in identifying and locating volcanic ash clouds, in particular
during the first few days after an eruption.
NASA, in collaboration with NOAA, provides near real-time
information on volcanic sulfur dioxide and ash aerosols from
the OMI instrument. NOAA provides this information to its U.S.-
based volcanic ash advisory centers. The international network
of these centers is charged with gathering information on the
presence and motion of volcanic clouds and assessing any
hazards to aviation. In April, NASA products were provided for
the first time to the European volcanic ash advisory centers to
assist in their decision making.
From a research perspective, NASA-developed global models
can be used to simulate the emission of volcanic ash and sulfur
dioxide into the atmosphere and to track its subsequent
transport and dispersion on regional and global scales. NASA
also routinely uses air particle trajectory modeling to
estimate the source regions of features seen in satellite data
that are suspected to have a volcanic origin. However, such
model runs are generally undertaken after an eruption has taken
place in order to advance scientific understanding, leading to
improvements in the accuracy of the models.
At present, our understanding of solid earth processes and
our ability to obtain adequate global measurements to initiate
the models are both insufficient for generating routine,
accurate predictions of volcanic ash plume range and
composition. However, NASA efforts to improve observations will
yield new and more refined data on various aspects of the plume
including area, height, aerosol properties and associated
sulfur dioxide which can be used to help critically evaluate
current models and drive the improvement of such models in the
future.
Thank you again for the opportunity to testify before you
today. I look forward to answering your questions.
[The prepared statement of Mr. Kaye follows:]
Prepared Statement of Jack Kaye
Good morning Chairwoman Giffords, Ranking Member Olson and Members
of the Subcommittee. I appreciate the opportunity to appear before you
today to discuss the National Aeronautics and Space Administration's
(NASA's) Earth Science-related activities to monitor and study volcanic
ash clouds. The recent eruption of Eyjafjallajokull highlights the
different types of contributions that NASA Earth Science makes to the
study of, and response to, such events. Through its fleet of satellite
assets, NASA is able to rapidly generate and broadly disseminate
imagery and data products on the location, heights, and densities of
ash plumes and related hazards. These data products fuel a range of
research investigations which enhance our knowledge of solid Earth
processes, atmospheric transport and composition, and the impacts that
volcanic eruptions have on the Earth system. NASA is also able to--and
did--provide critical data streams from these research satellites to
the National Oceanic and Atmospheric Administration (NOAA) to support
that agency's operational prediction of dust plumes. In response to the
intense public interest in this event, NASA has conducted focused
public outreach activities regarding our research capabilities and
science activities in the areas of volcano research and hazard
prediction. Although NASA does not have operational responsibility for
observation and analysis of volcanic gas and aerosol emissions, its
fleet of research spacecraft provides data that are directly applicable
to the societal hazards presented by these phenomena.
NASA has been using research satellites to study volcanic
eruptions, especially their atmospheric impact, for more than three
decades. NASA pioneered such activities using the Total Ozone Mapping
Spectrometer (TOMS) instrument flying aboard the Nimbus 7 satellite
launched in 1978. The record for the Nimbus 7 TOMS and the flight of
successor TOMS instruments on other missions covers the years 1978-2003
and includes observations of a total of 274 eruptive events from 70
different volcanoes (see http://toms.umbc.edu/). Starting in 2004 and
extending to the present, key successor measurements are provided by
the Ozone Monitoring Instrument (OMI) flying aboard NASA's Aura
spacecraft.
Information on atmospheric composition in the TOMS/OMI data is
based on measurements of ultraviolet radiation; however, this is only
one of the ways in which NASA uses its satellites to study the
atmospheric impact of volcanic eruptions. NASA's currently operating
fleet of 13 satellite missions is being used to generate several data
products which provide complementary information on volcanic effects on
the atmosphere through measurements obtained from different wavelength
regions, viewing geometries, and employing a variety of remote sensing
technologies. These products provide information not only on the
location of ash clouds and sulfur dioxide (SO2) injected
into the atmosphere, but on the height, size, and composition of the
particles. Such data are critically important for the initialization
and evaluation of the models that are used to predict the evolution of
the gas and ash plumes associated with volcanic eruptions, as well as
for direct guidance as to the location and severity of ash plumes.
Monitoring Eyjafjallajokull Using NASA Assets
NASA's satellites have observed the ash plume since the eruption of
Eyjafjallajokull, providing essential data on the size and composition
of the plume as it expanded and moved over Europe. For example, data
acquired by the Multi-angle Imaging SpectroRadiometer (MISR), one of
the instruments on NASA's TERRA spacecraft (launched in 1999) provided
information on both the horizontal and vertical extents of the plume.
The Moderate Resolution Imaging Spectroradiometer (MODIS) instruments
on the Terra and Aqua (launched in 2002) satellites captured images of
the eruption; the multiple wavelength measurements provided by the
MODIS instruments aid researchers in separating ash plumes from clouds
in the imagery. Information on the height of the ash plume was also
provided by MODIS. NASA was able to validate the Terra and Aqua ash
plume height observations using data from the Cloud-Aerosol Lidar and
Infrared Pathfinder Satellite Observations (CALIPSO) satellite,
launched in 2006. CALIPSO's active remote sensing (lidar) approach not
only detects aerosols (small particles such as dust, smoke and
pollution) and thin clouds that are often invisible to radar, but
determines their heights and vertical concentration profiles. The
Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER)
instrument, also onboard Terra, is able to detect and track lava flows,
as well as ash and gas plumes, with high spatial resolution. For the
Eyjafjallajokull eruption, additional thermal and visible images of the
plume were captured using the Atmospheric Infrared Sounder (AIRS)
instrument on Aqua and the Hyperion instrument on Earth Observing-1
(EO-I), launched in 2000. The data and images are archived and
available from the NASA Earth Observing System Distributed Active
Archive Center. Select imagery can be accessed at: http://
earthobservatory.nasa.gov/NaturalHazards/event.php?id=43253.
In addition to providing measurements and information to aid
decision-makers in responding to the volcanic event and its aftermath,
these data from NASA's research satellites are being utilized in
several ongoing NASA-sponsored scientific studies of solid Earth
processes, atmospheric composition and air quality, Earth's radiation
balance, and aviation forecasting improvement methodologies within
NASA's Earth Science Division's Research and Analysis (R&A) and Applied
Sciences programs.
For example, over the past several years a project competitively
funded through NASA's Applied Sciences Program demonstrated reliable
and accurate detection of volcanic ash clouds using observations of
sulfur dioxide (SO2) from the Ozone Monitoring Instrument
(OMI) onboard the NASA Aura satellite. SO2 is a reliable
marker for fresh ash clouds from explosive magmatic eruptions as it
provides a clear discrimination between volcanic plume and ordinary
clouds. Since volcanic eruptions are essentially the only large sources
of stratospheric SO2, false alarms are non-existent.
Satellite observations of SO2 thus assist operational
agencies to identify and locate volcanic ash clouds, in particular
during the first few days after an eruption. In general the ash in a
volcanic plume will drop due to gravity effects faster than the
SO2, so that some distance away from the volcano the ash and
SO2 clouds may be separated. Details of how this Applied
Sciences work is now being used in an operational regime are presented
in the next section.
Collaboration with U.S. and International Organization to Monitor
Volcanic Ash Plumes
NASA works with other agencies to ensure that data from NASA's
research satellites can be used to meet operational needs. For example,
NASA, in collaboration with NOAA, provides information on volcanic
sulfur dioxide (SO2) and ash aerosols from OMI aboard the Aura
satellite every three hours after the data is acquired. This
information is used to supplement data from NOAA's Geostationary
Operational Environmental Satellites (GOES) and Polar Operational
Environmental Satellite (POES) fleets. NOAA distributes these data on-
line to its Volcanic Ash Advisory Centers (VAACs) at: http://
satepsanone.nesdis.noaa.gov/pub/OMI/OMISO2/index.html. Nine VAACs were
founded in 1995 as a part of an international system set up by the
International Civil Aviation Organization (ICAO) called the
International Airways Volcano Watch (IAVW). The VAACs are charged with
gathering information on the presence and motion of volcanic clouds and
assessing any hazards to aviation. They issue advisories and alerts to
airline and air traffic control organizations on the possible danger of
volcanic clouds. VAACs assist the aviation community to utilize
satellite data, pilot reports, and other sources of information to
detect and track ash clouds, and to use trajectory and dispersion
models to forecast the motion of ash plumes.
At the time of the latest eruption, SO2 information was
being made routinely available for sectors covering the Americas and
the Pacific, through the Anchorage and Washington Volcanic Ash Advisory
Centers (VAACs). However, beginning on April 19, 2010, NASA began to
provide this information for sectors covering Iceland and Northwest
Europe to the VAAC in London. This information is now being utilized in
the formulation and validation of Volcanic Ash Advisories over Europe.
As an additional response to the eruption, the Support to Aviation
Control Service (SACS), a support center for the European VAACs, is now
directly linking to the Aura/OMI near-real time products (http://
sacs.aeronomie.be/). The SACS SO2 data and alert service
delivers near-real time data derived from satellite measurements
regarding SO2 emissions possibly related to volcanic
eruptions, and in case of exceptional SO2 concentrations
(``SO2 events'') can use the data to send out alerts by
email to interested parties. When volcanic activity poses a hazard to
aviation, the VAACs issue alerts to air traffic control and airline
organizations to help them decide whether to reroute planes away from
volcanic clouds. In the case of the Eyjafjallajokull eruption, the
satellite measurements and products were also directly shared with
Schiphol Airport (Amsterdam) and the Netherlands Ministry of Traffic
Affairs through the OMI Principal Investigator at the Royal Netherlands
Meteorological Institute.
Future NASA Assets With Volcanic Ash Monitoring Applications
Several of the research satellite missions that NASA is currently
developing will be able to provide new and advanced insights into
volcanic ash cloud properties.
Later this year, NASA will launch the Glory mission to study the
Earth's energy budget and the presence of aerosols in the atmosphere.
Glory will be able to distinguish various species of aerosols,
information which will advance the study of volcanic effluent
composition.
In 2011, NASA is scheduled to launch the NPOESS Preparatory Project
(NPP). The Visible/Infrared Imager Radiometer Suite (VIIRS) instrument
on NPP is designed as an operational follow-on to the research-grade
MODIS instrument on Terra and Aqua. The Ozone Mapping and Profiler
Suite (OMPS) on NPP will provide data that to continue support for the
detection of volcanic ash clouds using SO2 observations,
currently performed by Aura/OMI. Operational availability of VIIRS data
will continue on the Joint Polar Satellite System, scheduled for launch
in 2015.
The 2007 National Research Council (NRC) Decadal Survey recommended
several missions that promise to advance future volcano research. The
Deformation, Ecosystem Structure and Dynamics of Ice (DESDynI) mission,
a Tier 1 mission, has as a key mission objective to improve the
determination of the likelihood of earthquakes, volcanic eruptions, and
landslides. This will enhance our ability to anticipate future
eruptions, whereas the response to the Eyjafjallajokull eruption was
reactive. Likewise, the Tier 2 Hyperspectral Infrared Imager (HyspIRl)
mission would include measurements over a range of optical and infrared
wavelengths useful for detecting volcanic eruptions, determining the
ash content of volcanic plumes, and identifying the occurrence and
effects of associated landslides. The Geostationary Coastal and Air
Pollution Events (GEO-CAPE) mission, also a Tier 2 mission, would
measure aerosols and allow the tracking of pollutants being transported
in the atmosphere. Similarly, data from the Tier 2 Aerosol-Cloud-
Ecosystems (ACE) mission would be able to distinguish volcanic aerosols
from other aerosol types and clouds, and will track the dispersion of
volcanic plumes in three dimensions on a global basis.
Improvements to Volcanic Ash Plume Modeling
NASA-developed global models can be used to simulate the emission
of volcanic ash and SO2 into the atmosphere, and to track
its subsequent transport and dispersion on regional and global scales.
NASA also routinely uses air parcel trajectory modeling to estimate the
source regions of features seen in satellite data that are suspected to
have a volcanic origin. However, such model runs are generally
undertaken after an eruption has taken place in order to advance
scientific understanding, leading to improvements in the accuracy of
the models. At present, our understanding of solid Earth processes and
our ability to obtain adequate global measurements to initiate the
models are both insufficient for generating routine, accurate
predictions.
The mandate of NASA's Earth Science program is to increase
scientific understanding of Earth processes as an integrated system.
NASA thus does not produce routine, operational predictions of volcanic
ash and SO2 cloud transports and evolution. Because there is
a lack of immediately available information on the quantity and
characteristics of emissions from any particular volcano, any forecasts
of ash and SO2 emission and propagation are relatively
crude. With the present ``state of the art,'' estimates of SO2
cloud transport and characteristics are based heavily on estimates of
emitted SO2, and while model results usually match well with
observed cloud dispersion and distribution, they do not produce
reliable estimates of SO2 concentrations. At this time, air
parcel trajectory models, in which columns of air parcels are
initialized over erupting volcanoes at the time of the eruption and
then tracked as the parcels are transported away from the volcano
location by forecast wind fields, estimate the evolution of the ash
cloud but do not consider important loss processes such as fallout,
rainout, and washout, precluding a reliable forecast of ash cloud mass
loading.
The Global Modeling and Assimilation Office at NASA Goddard Space
Flight Center generates weather forecasts for the NASA research
community, using the Goddard Earth Observing System--Version 5 (GEOS-5)
Data Assimilation System. This system includes an aerosol model,
Goddard Chemistry Aerosol Radiation and Transport (GOCART), as part of
its routine twice-daily weather forecast. GOCART must be forced with
appropriate emissions and produces 3-dimensional distributions of
aerosols during the forecast period. At present, the GEOS-5 system
includes an inventory of continuously outgassing volcanoes, but
episodic volcanic eruptions are not included.
Routine forecasts of the propagation of volcanic ash and SO2
clouds following an eruption using the GEOS-5 system would be possible
given some modifications. More detailed observations of the
constituents of the ejecta and their vertical distribution are
required. Observations need to include information about the timing and
duration of the eruptions, the injection altitudes as a function of
time, and the particular characteristics of the emissions (amount,
size, type). The information would need to be made available or
converted to machine-readable data files with time of eruption,
location, plume height and strength of the emission in terms of
SO2 and ash. The GOCART aerosol model would need to be
modified explicitly to include a volcanic ash constituent. A third area
of improvement is the development of statistical models of uncertainty
useful to decision makers. For this, an ensemble forecasting technique
would be necessary, spanning likely scenarios of ejecta and their
vertical distribution as well as weather forecast uncertainty.
The London VAAC runs a version of the Numerical Atmospheric-
dispersion Modeling Environment (NAME) model (http://
www.metoffice.gov.uk/aviation/vaac/eruption-detection.html).
The London VAAC has used the OMI aerosol index (AI) to validate their
dispersion model output, although their main source of satellite data
has been the Spinning Enhanced Visible and Infra-Red Imager (SEVIRI)
infrared instrument on the European geostationary Meteosat Second
Generation (MSG) satellite, which has better temporal resolution than
the polar-orbiting OMI. However, their automatic system based on SEVIRI
detects only about 2/3 of the eruptions. Using near real time
ultraviolet data, such as OMI Aerosol Index and SO2 (as an
ash proxy) in addition to thermal infrared data could improve early
(thick) volcanic plume detection, not visible in the infrared.
NASA recently began providing OMI near real time SO2 and
AI data to Operations Department of the European Centre for Medium
Range Weather Forecasts (ECMWF) for evaluation in assimilation tests.
The goal is to create an advanced operational data assimilation system
that will: (1) reasonably model a volcanic plume (given the
uncertainties in injection height, and composition of the plume); (2)
assimilate available satellite near-real-time data to constrain the
model forecast; and (3) provide forecasts for the VAACs.
It is important to note that the North American-Asia air traffic
routes overfly the volcanic arcs of the North Pacific from Tokyo, Japan
to Anchorage, Alaska. These are among the most violent and active
volcanoes on Earth. The Washington and Anchorage VAACs, operated by
NOAA, have a stellar record of tracking, monitoring and warning of
volcanic ash dispersion. These VAACs run NOAA's HYbrid Single-Particle
Lagrangian Integrated Trajectory (HYSPLIT) model. They utilize
operational NOAA GOES and POES satellite data, NASA research
observations, as well as data leveraged from European, Japanese,
Indian, and other environmental satellites. The Washington and
Anchorage VAACs' areas of responsibility extend from South America
through the Caribbean and cover the continental United States, Alaska,
and most of the Pacific.
Airborne Assets With Volcano-Monitoring Capabilities
Volcano remote sensing researchers have a strong need for in situ
sampling of eruption plumes and drifting ash clouds to improve,
calibrate and validate ash dispersal models. Airborne assets are
uniquely qualified to measure the gas and ash content of volcanic
plumes at altitude. However, sampling a volcanic plume is also a
hazardous procedure given the dangers that volcanic-ash contamination
poses to aircraft engines.
The United States maintains both research and operational airborne
assets that could be used to monitor future eruptions. However, NASA's
research aircraft and unmanned aerial vehicles are typically engaged in
coordinated field campaigns investigating other science research
questions, but could be diverted to a hotspot on an emergency basis.
Such a decision would constitute an interruption to the baseline
mission profile and would require at least a one week lead time in
order to position the aircraft, instruments, and crew.
One such asset is NASA's ER-2 aircraft, which could be instrumented
with the Cloud Physics Lidar (CPL) and Airborne Visible/Infrared
Imaging Spectrometer (AVIRIS) in order to study atmospheric particles.
In the future, NASA's new high-altitude, long-endurance, heavy-lift
Global Hawk unmanned aerial system might also be utilized for volcanic
plume monitoring. The Global Hawk is still in its development phase, so
rapid response use will be limited for the next few years as NASA gains
operational experience with the Global Hawk and integrates new
instruments onto the platform.
Conclusion
As the Eyjafjallajokull eruption has shown, volcanic eruptions have
a significant impact on the Earth's atmosphere and the planes that
travel through that airspace. Although NASA does not have an
operational requirement to monitor and predict volcanic ash plumes,
existing and planned NASA assets provide essential data on volcanic
emissions that can be used by operational agencies around the world to
determine if there are hazards to aircraft. NASA's satellites and
associated research programs have added significantly to our ability to
observe not just the position of volcanic ash plumes, but to understand
their composition, height, and properties. Through the NASA Applied
Sciences Program, we can facilitate the use of the data collected by
NASA's research satellites in operational regimes. NASA researchers are
developing and improving models that can be used to predict how
volcanic ash plumes will propagate. While there are still areas for
improvement, NASA's Earth Science Division supports this work through
new instruments and satellites and continued work in its Applied
Sciences and Research Programs.
Biography for Jack Kaye
Jack Kaye currently serves as Associate Director for Research of
the Earth Science Division (ESD) within NASA's Science Mission
Directorate (SMD). He has been a member of the Senior Executive Service
since August, 1999, managing NASA's Earth Science Research Program.
Earlier positions in his more than 26 year career at NASA include being
a Space Scientist at the Goddard Space Flight Center and Manager of the
Atmospheric Chemistry Modeling and Analysis Program at NASA HQ. In
addition, he has held temporary acting positions as Deputy Director of
ESD and Deputy Chief Scientist for Earth Science within SMD. His
academic training is in chemistry (B.S. Adelphi University, 1976;
Ph.D., California Institute of Technology, 1982). He also held a post-
doctoral research associateship at the U.S. Naval Research Laboratory.
As Associate Director for Research, Dr. Kaye is responsible for the
research and data analysis programs for Earth System Science, covering
the broad spectrum of scientific disciplines that constitute it.
He represents NASA in many interagency and international activities
and has been an active participant in the U.S. Global Change Research
Program (USGCRP) in which he has served for several years as NASA
principal and Vice Chair of the Subcommittee on Global Change Research
(since Jan. 20, 2009 he has served as the Acting Chair for these
activities). He also serves as NASA's representative to the Senior
Users' Advisory Group for the National Polar Orbiting Operational
Environmental Satellite System and to the Joint Subcommittee on Ocean
Science and Technology. He is a member of the Steering Committee for
the Global Climate Observing System and is an ex officio member of the
National Research Council's Roundtable on Science and Technology for
Sustainability. He has received numerous NASA awards (most recently,
the Outstanding Leadership Medal in 2009), as well as been recognized
as a Meritorious Executive in the Senior Executive Service in 2004. He
was elected to serve as co-secretary of the Atmospheric Sciences
Section of the American Geophysical Union (AGU) for 1998-2000 and
earlier served on the AGU Publications Committee. The AGU has
recognized him on two occasions with a Citation for Excellence in
Refereeing. He has published more than 50 refereed papers, contributed
to numerous reports, books, and encyclopedias, and edited the book
Isotope Effects in Gas-Phase Chemistry for the American Chemical
Society. In addition, he has attended the Leadership for Democratic
Society program at the Federal Executive Institute and the Harvard
Senior Managers in Government Program a the John F. Kennedy School of
Government at Harvard University.
Chairwoman Giffords. Thank you, Dr. Kaye. We appreciate
your testimony. The volcano who normally goes unnamed, I
appreciate your courage in attempting to pronounce the name
correctly. I appreciate that. Welcome.
Ms. Cox, please.
STATEMENT OF VICTORIA COX, SENIOR VICE PRESIDENT, NEXTGEN AND
OPERATIONS PLANNING, AIR TRAFFIC ORGANIZATION, FEDERAL AVIATION
ADMINISTRATION
Ms. Cox. Thank you, Chairwoman Giffords, Ranking Member
Olson, members of the Subcommittee. Thank you for inviting me
to testify today on mitigating the impact of volcanic ash
clouds on aviation.
The FAA has dealt with the issue of volcanic ash clouds
before, both from a research and an operational perspective,
and we are happy to share this information with the
Subcommittee.
Volcanic eruptions are not unusual. In fact, there is
almost always an eruption somewhere in the world that may pose
a hazard to international air navigation. What is rare are
accidents and incidents resulting from encounters with volcanic
ash. FAA's voluntary reporting databases show only five
encounters and 20 complications due to volcanic ash since 2007.
When compared to the thousands of aviation operations taking
place in the national airspace system every day, this is indeed
a small number.
The FAA's primary method of dealing with volcanic ash
events is operator avoidance. Since the geographical location
of areas that may be affected by volcanic ash is weather
dependent, our model of managing air traffic when confronted
with volcanic ash is to treat it much like a major weather
event. That is, we gather the information from the reporting
agencies and disseminate that information to the operators of
aircraft. In turn, the operator makes the decision of go or no
go. If the operator chooses to fly, then our air traffic
controllers will direct the operator around volcanic ash to the
best of our abilities.
Our past participation in volcanic ash research reflects
this. Because the FAA is essentially a consumer of weather
services that can help tell us where the volcanic ash will
disperse, we have worked with the weather reporting agencies to
develop weather products specifically for aviation use.
The European response to last month's volcanic eruption in
Iceland was generally to close the airspace where volcanic ash
could pose a threat to aviation safety. This may have been due
to the constrained airspace over Europe that limited the
possibility of reroutes as well as the need to coordinate the
actions of the multiple civil aviation authorities in the
various countries of the European Commission.
After the shutdown of airspace, European regulators were
faced with the challenge of reopening their airspace, and the
FAA was able to lend its expertise to our counterparts in
Europe. FAA air traffic personnel also participated in daily
telephone conferences with the United Kingdom's Civil Aviation
Authority and the interdisciplinary group that they assembled.
While we primarily offered information on our operator
avoidance practices, we also helped to brainstorm operational
solutions for reopening European airspace such as developing a
collaborative volcanic ash forecasting process and developing
pathfinder test flight traffic patterns between cities with low
ash impact.
I know that this Committee is interested in how the Next
Generation Air Transportation System, NextGen, may affect our
current model of operator avoidance when confronted with
volcanic ash. Because the issue is really based upon receiving
the best information, NextGen will enable an improved
information-sharing process. NextGen focuses on how to best put
information in a format that can be used by pilots, controllers
and dispatchers, and integrated into decision support tools.
Volcanic ash information is treated like significant
weather information. Under NextGen, the NextGen Network Enabled
Weather product enables the publication of the same weather
information to all airspace users. The role of NOAA, the
National Oceanic and Atmospheric Administration, is to provide
quality data to all its users including data that meets the
FAA's air traffic control requirements. The FAA integrates the
information provided by NOAA into tools expressly for air
traffic management. NextGen will help improve the quality and
delivery of information to the FAA and aviation users, enabling
all of us to make better informed operational decisions when
confronted with adverse conditions such as volcanic ash.
Madam Chairwoman, Ranking Member Olson, members of the
Subcommittee, this concludes my prepared remarks. Thank you
again for inviting me here today to discuss the impact of
volcanic ash on aviation operations. I would be happy to answer
any questions you may have.
[The prepared statement of Ms. Cox follows:]
Prepared Statement of Victoria Cox
Chairwoman Giffords, Ranking Member Olson, Members of the
Subcommittee: Thank you for inviting me to testify before you today on
mitigating the impact of volcanic ash clouds on aviation. The Federal
Aviation Administration (FAA) has dealt with the issue of volcanic ash
clouds before, both from a research and an operational perspective, and
we are happy to share this information with this Subcommittee.
Effects of Volcanic Ash on Aircraft
Volcanic ash is extremely damaging to aircraft. Should an aircraft
encounter volcanic ash during flight, it could ingest the ash into the
engines. If the volcanic ash passes through the turbine engines of an
aircraft, the burner section can melt the ash, which then can deposit
on the turbine's nozzles as a hard glaze. This can negatively affect
the engine's operation and can result in a loss of power or total
shutdown of the engine. When an engine loses power or shuts down due to
turbine nozzle glazing, it will cool down rapidly. This can result in
the fracturing of the volcanic ash glaze. Once the glazing breaks up
and falls away, the engine may be able to resume normal operation.
There are additional negative effects of volcanic ash on an
aircraft turbine engine. These may include erosion of compressor blades
and rotor-path components as well as turbine cooling passages,
contamination of the oil system and bleed air system, and plugging of
the engine's inlet pitot static probes. These effects can cause severe
and costly damage to an aircraft and its components.
FAA Volcanic Ash Response
While the severe impact of a major volcanic event such as we saw in
Europe last month is extremely unusual, volcanic eruptions are not
unusual. There is almost always an eruption somewhere in the world that
may pose a concern to international air navigation. In certain parts of
the United States, such as Alaska, volcanic eruptions are enough of a
possibility that the FAA has developed an operational response.
FAA Orders 7900.5B and 7110.65T and JO 7930.2M Notice to Airmen
(NOTAM) provide operational information regarding volcanic ash. The
FAA's primary method of dealing with volcanic ash events is operator
avoidance. Since the geographical location of areas that may be
affected by volcanic ash is weather-dependent, our model of managing
air traffic when confronted with volcanic ash is to treat it much like
a major weather event. That is, we gather the information from the
reporting agencies and disseminate that information to the operators of
aircraft. In turn, the operator makes the decision to fly or not. If
the operator chooses to fly, then our air traffic controllers will
direct the operator around the volcanic ash to the best of our
abilities.
As an additional safety precaution, on April 22, 2010, the FAA
issued a Special Airworthiness Information Bulletin, NE-10-28,
regarding turbine engine operation in volcanic ash airspace. The FAA
noted that before flying from the United States to Europe or within
Europe, aircraft owners and operators should review the following
recommendations:
Although the FAA does not recommend engine operation
or flight into a visible volcanic ash cloud, we do recommend
that aircraft owners and operators obtain definitive
information on operational limitations around ash clouds, if
any, from each of the European National Authority of the
State(s), over which they plan flight operations.
Follow all aircraft and engine manufacturer's
operating and maintenance instructions pertaining to operations
in airspace where volcanic ash may be near or present.
Report any inadvertent encounter with volcanic ash or
relevant findings, including abnormal engine behavior, to the
respective type certificate holders of the aircraft and
engines.
FAA Past Volcanic Ash Research Efforts
In the 1990s, the International Civil Aviation Organization (ICAO)
established Volcanic Ash Advisory Centers (VAAC) that disseminate
information worldwide on atmospheric volcanic ash clouds that may
endanger aviation. There are nine VAACs located around the world run by
local weather forecasting organizations. In the United States, the
National Oceanic and Atmospheric Administration (NOAA) runs VAACs in
Anchorage, Alaska and Washington, D.C.
In the past, the FAA has participated with other Federal agencies
on developing a national plan for dealing with volcanic ash with regard
to aviation operations. Under the auspices of the Office of the Federal
Coordinator for Meteorological Services and Supporting Research (OFCM),
led by NOAA, the FAA helped develop the National Volcanic Ash
Operations Plan for Aviation.
Because the FAA is essentially a consumer of weather services, we
work with the weather-reporting agencies to develop weather products
specifically for aviation use. Our role in that partnership is to set
the requirements of what the weather products must provide in order to
be useful for aviation users, whether they are air traffic controllers
or pilots. Accordingly, our participation in the OFCM project was
primarily to set the requirements for the development of volcanic ash
information products for the FAA and aviation operators to use.
Aviation operations in volcanic ash situations rely on information
based on detection and monitoring, alerting, modeling, and post event
assessments. The U.S. Geological Survey (USGS) provides seismic
monitoring for early detection and passes the information directly to
the FAA to provide early warnings when an eruption is imminent or has
occurred, which is especially important for en route aircraft. NOAA
uses satellite monitoring as a core element in detection, tracking, and
monitoring eruptions, and the resultant ash plume. Pilots also make
observations, and the FAA disseminates pilot reports or PIREPS along
with NOTAMs and Significant Meteorological Information (SIGMETs).
SIGMETS originate from NOAA's National Weather Service.
Much of the capability to predict dispersion of volcanic ash clouds
is based on mathematical modeling. The HY-SPLIT (HYbrid Single-Particle
Lagrangian Integrated Trajectory) model is the current model in use by
NOAA and Australia's Bureau of Meteorology and its Darwin VAAC. Other,
similar, models are used by other VAACs. Post assessment is carried out
by the USGS, NOAA and the Smithsonian to determine how we can improve
the services provided to industry and the FAA's air traffic management.
FAA Assistance in Response to Eyjafjallajokull Eruption
The European response to last month's volcanic eruption in Iceland
was generally to close the airspace where volcanic ash could pose a
threat to aviation safety. This was due in part to the constrained
airspace over Europe and the need to coordinate the actions of the
multiple civil aviation authorities of the various countries of the
European Commission.
After the shutdown of airspace, European regulators were faced with
the challenge of reopening their airspace, and the FAA was able to lend
its expertise to our counterparts in Europe. FAA air traffic personnel
also participated in a daily telephone conference with the United
Kingdom's Civil Aviation Authority and the inter-disciplinary group
they assembled. While we primarily offered information on our operator
avoidance practices, we also helped to brainstorm operational solutions
for reopening European airspace such as developing a collaborative
volcanic ash forecasting process and developing ``pathfinder'' test
flight traffic patterns between cities with a low ash impact.
NextGen and Volcanic Ash
I know that this Committee is interested in how the Next Generation
Air Transportation System (NextGen) may affect our current model of
operator avoidance when confronted with volcanic ash. Because the issue
is really based upon receiving the best information, NextGen will
enable an improved information sharing process. NextGen focuses on how
to best put information in a format that can be used by pilots,
controllers, and dispatchers and integrated into decision support
tools.
Volcanic ash information is treated like significant weather
information. Under NextGen, the NextGen Network Enabled Weather (NNEW)
product will enable the publication of the same weather information to
all airspace users. NOAA's role will be to provide quality data to all
its users including data that meets the FAA's air traffic control
requirements. The FAA will integrate the information provided by NOAA
into tools expressly for air traffic management. NextGen will help
improve the quality and delivery of information to the FAA and aviation
users, enabling all of us to make better informed operational decisions
when confronted with adverse conditions such as volcanic ash.
Madame Chairwoman, Ranking Member Olson, Members of the
Subcommittee, this concludes my prepared remarks. Thank you again for
inviting me here today to discuss the impact of volcanic ash on
aviation operations. I would be happy to answer any questions that you
may have.
Biography for Victoria Cox
As the Air Traffic Organization's Senior Vice President for NextGen
and Operations Planning, Vicki Cox provides increased focus on the
transformation of the nation's air traffic control system by providing
systems engineering, research and technology development, and test and
evaluation expertise. She is also responsible for the NextGen portfolio
and its integration and implementation.
Within the FAA, Cox has served as the Director of the ATO's
Operations Planning International Office, the Director of Flight
Services Finance and Planning and the Program Director of the Aviation
Research Division.
Prior to joining the FAA, Cox was Director of International
Technology Programs in the Office of the Director of Defense Research
and Engineering in the Office of the Secretary of Defense. She has an
extensive research and development and program management background,
having supported the Deputy Undersecretary of Defense for Science and
Technology as the DOD Laboratory Liaison. She also worked as a Program
Manager for a number of ballistic missile defense technology programs
for the U.S. Air Force. A physicist, Cox served as Chief of Physics and
Scientific Director of the European Office of Aerospace Research and
Development in London. She also worked as a scientist responsible for
thermal vacuum conditioning and testing of the Hubble Telescope for
NASA.
Cox graduated from Converse College and received a Master's degree
from East Carolina University. She has a certificate in U.S. National
Security Policy from Georgetown University and is a DOD Level III
Certified Acquisition Professional in Systems Planning, Research,
Development and Engineering. She also earned her private pilot's
license in 1985.
Chairwoman Giffords. Thank you, Ms. Cox. We are glad you
are here with us.
Captain Orlady.
STATEMENT OF CAPTAIN LINDA M. ORLADY, EXECUTIVE AIR SAFETY VICE
CHAIR, AIR LINE PILOTS ASSOCIATION, INTERNATIONAL
Ms. Orlady. Madam Chair, Ranking Member Olson, members of
the Subcommittee, I am Captain Linda Orlady, Executive Air
Safety Vice Chair of the Air Line Pilots Association
International representing the safety interests of more than
53,000 professional pilots in the United States and Canada. On
behalf of our members, I thank you for this opportunity to
testify on volcanic ash and the risks it poses to aviation.
Fifty-five to 60 volcanic eruptions annually worldwide and
resulting ash and gases reach altitudes routinely traveled by
the airlines. As vividly demonstrated during the recent
Icelandic eruption, ash cloud can drift for days, weeks,
contaminate large areas of airspace. Flying in volcanic ash and
gases poses a significant but little understood threat to the
integrity of aircraft, its engines and to the health of its
occupants.
Although no fatal airline accidents have been attributed to
volcanic ash, damage to aircraft, potential damage to
passengers and crew have been well documented. Two notable
involved a British Airways 747 flight over Indonesia in 1982
and a KLM 747 flying over Alaska in 1989. Both of these
aircraft lost power to all four engines during an inadvertent
volcanic ash encounter. In each case, the pilots struggled to
restart engines, handle other malfunctions and managed to
safely land badly damaged aircraft. The encounters caused
extensive damage to the engines, windshields and other aircraft
systems. Documented volcanic ash encounters have revealed these
vulnerabilities. Further study is required to fully understand
our susceptibilities to volcanic ash and gas cloud
contamination.
Additionally, volcanic gases pose serious health hazards to
aircraft crew and passengers including breathing difficulties,
headaches, itchy eyes. Volcanic gases can produce an acrid odor
which may mislead a flight crew into thinking they have an
electrical problem or might mask the presence of an actual
electrical problem. Volcanic ash cloud gases are not displayed
on cockpit radar nor on radar at air traffic control. They are
extremely difficult to detect at night. Pilots must rely on
information from dispatchers, other pilots to determine the
location of these hazards. Coordinating and standardizing this
information is further complicated by the number of different
entities who supply it.
The recent Icelandic eruption demonstrated a lack of
standardization between the various forecasts available to
flight crews and dispatchers. As operations resumed in Europe,
we received reports from pilots at different airlines who were
given conflicting information in their dispatch release
documents. In some cases, pilots had one depiction showing
extensive air coverage while others showed nothing at all.
While we have made progress in predicting where and when an
eruption may occur, work must be done to improve forecasting
and standardizing information about where and how an ash cloud
will spread.
The recent air travel disruption demonstrated the benefit
of having data to reliably and objectively define a specific
hazard area, potentially allowing flights into some regions.
However, we did not have scientifically reliable data to make
that determination. Arrays of potential hazards cannot
currently be defined in terms that flight crews can use for
dispatching while airborne.
ALPA is encouraged the Senate version of the FAA
reauthorization bill supports research on volcanic ash hazards.
We urge Congress to enact this legislation. Without such
research to improve the understanding of the hazards and ways
to mitigate them, ALPA continues to advocate that the only safe
course of action for flight crews is to avoid any encounter
with volcanic ash. We need to determine if scientifically
validated threshold levels developed with stakeholder
participation can define an acceptable ash encounter. This
determination must be based on rigorous, structured testing and
produce reliable, scientifically quantifiable results. It will
never be acceptable to hope for the best as we see how close we
can fly to an ash cloud.
To continue operating in areas where there is a risk of
flight into volcanic ash, ALPA believes we need several
improvements. First, onboard systems to detect ash clouds
concentrated volcanic gases which allow pilots enough time to
identify potential hazards and sufficient time to provide for
safe navigation around them. Secondly, more vigorous aircraft
certification standards. Thirdly, new procedures and training
programs for flight crews, dispatchers, mechanics and air
traffic controllers.
As a rare but positive example, Alaska Airlines has
developed volcanic ash training scenarios. They provide tools,
techniques for both avoidance and recovery from inadvertent
entry into volcanic ash and gas cloud conditions.
Unfortunately, this type of comprehensive training is not
universal for airlines operating in the vicinity of potential
volcanic activity.
Thank you for the opportunity to testify on this important
topic.
[The prepared statement of Captain Orlady follows:]
Prepared Statement of Linda Orlady
Ms. Chairwoman and members of the Subcommittee, I am Captain Linda
Orlady, Executive Air Safety Vice-Chair of the Air Line Pilots
Association, International (``ALPA'') which represents the safety
interest of over 53,000 professional pilots at 38 airlines in the
United States and Canada. On behalf of our members, I thank you for
this opportunity to testify before you on the issue of volcanic ash and
the risk it poses to aviation.
There are 1,500 known volcanoes around the world, and 600 (40%) of
them are currently listed as active. Collectively, there are 55 to 60
volcanic eruptions annually, and the ash and gases propelled from these
eruptions reach altitudes that are routinely traveled by the airlines.
Flying in the presence of volcanic ash and gases poses a significant,
but unfortunately little understood threat to the integrity of an
aircraft, its engines, and to the health of all occupants onboard.
Adding to these threats is the disturbing fact that volcanic ash clouds
and gases are not displayed on either radar installed in the aircraft
or on radar used by air traffic controllers. Furthermore, volcanic ash
and gas conditions are extremely difficult to identify at night. When
trying to avoid drifting ash clouds or gases, pilots must rely on
forecasts from dispatchers, reports from air traffic controllers, or
feedback from other pilots flying in the area to determine the location
of these potential hazards. The coordination and standardization of
this information is further complicated by the number of different
entities who supply information to airlines and their crews.
The recent Icelandic eruption demonstrated quite clearly that there
is a lack of standardization between the various forecasts available to
flight crews and dispatchers. As operations resumed in Europe last
week, we received several reports from crews at different airlines who
were given conflicting information in their dispatch release documents.
In some cases, crews had one depiction showing extensive ash coverage
and yet another which showed nothing at all.
Although there have been no fatal commercial airline accidents
attributed to volcanic ash, the occurrence of damage to aircraft and
potential dangers to the passengers and crew have been well documented.
The two most notable incidents involved a British Airways 747-200
flight over Indonesia in 1982 and a KLM 747-400 flying over Alaska in
1989. Both of these aircraft lost power to all four engines during an
inadvertent volcanic ash encounter. In the case of the British Airways
incident, all four engines lost power when the flight, operating in
darkness, encountered a volcanic ash cloud invisible to them or the
aircraft's weather radar. The crew declared an emergency as the
airplane descended to about 12,000 ft where they were beneath the ash
cloud but near mountainous terrain. They were able to restart three of
the four engines but lost power to one of the three remaining engines
when they again encountered ash while attempting to remain clear of the
mountains! The crew was finally able to safely land the crippled
airplane with only two of the four engines operating and with badly
scratched windshields that impaired their visibility. Similarly, in the
case of the KLM incident, the crew was able to restart the engines and
safely land a crippled airplane, averting the loss of human life and a
catastrophic aviation event. In both cases, there was extensive damage
to the airplane engines, windshields, and environmental control
systems. Documented volcanic ash encounters such as these have revealed
the known vulnerabilities in current aircraft systems; however, as
aircraft are constructed and equipped with newer technologies such as
sophisticated electronic systems, we will need to study and understand
those susceptibilities to volcanic ash contamination.
The flight safety risk associated with operations in the vicinity
of volcanic ash clouds is not limited to just the vulnerability of the
aircraft, engines, and the onboard systems. There is also a potential
health hazard from the volcanic gases such as Sulfur Dioxide
(SO2) or Hydrogen Sulfide (H2S). For example,
SO2 can cause breathing difficulties if inhaled at
significantly high concentration levels. H2S may cause
headaches and itchy eyes. Indications that volcanic gases are present
include an acrid odor similar to electrical smoke, which may mislead
the crew into thinking they have an electrical problem and cause
further distractions or, worse yet, mask the presence of an actual
serious electrical problem. Prolonged exposure to H2S may
dull the sense of smell causing the flight crew to believe erroneously
that they are clear of the gaseous environment.
Since the occurrence of the two near catastrophic events cited
above, there has been an increased awareness in the airline community
of the potential hazards of ash encounters. The improved availability
of satellites coupled with technologies to transform satellite data
into useful information along with improved coordination among
international volcano monitoring facilities has helped to reduce the
number of volcanic ash encounters worldwide. To date, ALPA along with
the aviation industry has advocated for continued improvements in
forecasting capabilities and dissemination of information to enable
crews to safely avoid areas where there is a potential for a volcanic
ash encounter. One outcome of this advocacy has been the creation of
the Volcanic Ash Advisory Centers (VAAC), which is a network of nine
facilities located worldwide. Each VAAC monitors the status of the
active volcanoes within their assigned areas and disseminates
information as needed to enable aircraft to safely avoid flying in
hazardous volcanic ash conditions. ALPA continues to advocate for
improved monitoring and forecasting capabilities but currently
maintains the position, as is stated in the FAA Aeronautical
Information Manual, to avoid any encounter with volcanic ash.
As vividly demonstrated during the recent eruption of the
Eyjafjallajokull Volcano in Iceland, an ash cloud can drift for several
days, travel thousands of miles, and envelop large areas of airspace.
And while we have made progress in predicting where and when an
eruption may occur, as previously stated, there is still work needed in
forecasting and standardizing the information on where and how the
resulting ash cloud will spread. The seismic activities and events
leading up to the Eyjafjallajokull eruption were well monitored by the
London-based VAAC, and as a consequence, flight crews had ample
awareness of the imminent hazard and the possible need to re-route
their flights accordingly. Unfortunately, the resulting ash cloud was
so widespread that re-routing flights around European airspace to avoid
potentially hazardous areas was not a viable option. European
regulators, to their credit, recognized that in the absence of data
demonstrating that safe flight was possible, the prudent course of
action was to cease operations in the interest of safety. The
disruption in air travel service cost billions of dollars to the
industry and extreme inconvenience to the traveling public. The
conservative approach taken by authorities--to put safety ahead of
economic considerations--ensured that no lives were lost. However, the
extent of the impact on worldwide operations demonstrated clearly that
the strategy of circumventing an area of ash and gas is not necessarily
a practical solution. Just as clearly, the situation demonstrated the
benefit of having data to make it possible to reliably and objectively
define a specific hazard area, potentially making it possible for
flights to operate in some regions. The dilemma is that currently we do
not have scientifically reliable and valid data which tells us how that
might be accomplished. The areas of potential hazard cannot currently
be defined in terms that are useable to flight crews both for dispatch
and for use while airborne. Furthermore, the nature of potential damage
to airframes and engines is not well understood. ALPA agrees that
action is warranted to address future disruptions in service, however,
as the economic impacts are assessed and mitigation strategies
considered, the safety risk of flight operations in the vicinity of
volcanic ash clouds cannot be compromised. ALPA is encouraged that the
Senate version of the current FAA reauthorization bill contains
language supporting the importance of research into volcanic ash
hazards as well as other weather phenomena, and we urge the Congress to
continue efforts to enact this legislation. Without such research to
improve understanding of the hazards and ways to mitigate them, ALPA
continues to advocate that the only safe course of action is for flight
crews to avoid any encounter with volcanic ash.
If in the future, flight crews are allowed to fly in areas where
there is a potential to encounter volcanic ash or gas concentrations,
then any acceptable threshold established for safe operations within
this environment must be based upon credible scientific data, analysis,
and sound verification processes. New technologies will be needed to
ensure all associated hazards within the allowable pre-established
threshold are anticipated for and can be detected, measured, and safely
mitigated by the flight crew prior to any encounter.
Anticipate the hazard: Better forecasting methods and information
dissemination will be needed to enable crews to plan for and to
implement, if necessary, safe exit strategies in the event of a
volcanic ash encounter that exceeds the pre-determined limits of the
airplane. As noted earlier, the current products available to flight
crews vary widely in their interpretation of available data. These
products must be standardized so that flight crews operating in an
area, dispatchers on the ground, and air traffic controllers have a
common understanding of where the threats areas may be and what
mitigations may be possible. In addition, flight crew training programs
must accommodate scenarios designed to help crews understand when
volcanic effects are a potential hazard, how to recognize and cope with
those effects, and how to develop effective exit strategies. This
challenge is particularly true for carriers whose typical route
structure involves flight in areas of known volcanic activity. Alaska
Airlines, for example, has developed extensive classroom and scenario-
based simulator training that provides crews with effective tools and
techniques that can be used in the event of inadvertent airborne ash
cloud exposure. In this training, pilots face a full range of hazards,
both to the aircraft and to its occupants, and develop strategies for
successfully recovering from such an emergency. More importantly,
awareness of and simulated exposure to ash and gas clouds underscores
the need for avoidance of these hazards. This type of comprehensive
training, however, is not universal for airlines that may operate in
the vicinity of volcanic activity. Detailed study of the effects of ash
and gas on aircrews and airplanes must be undertaken and this
information must be incorporated in training programs for crews
operating in potential threat areas.
Detect & Measure the hazard: Currently, ATC and aircraft radars do not
distinguish ash clouds from other weather related clouds. Crews may not
realize they have entered a hazardous volcanic ash situation until they
are already in it. By that time damage may have already occurred to the
airplane engines and/or other flight systems. Forward looking systems
are needed to detect an ash cloud and gases ahead of the airplane at
sufficient distances to allow adequate time for the crew to safely
divert around an unacceptable hazard. The forward looking system will
also need to measure vital characteristics of the volcanic cloud, such
as density and hazardous gas levels, to enable the crews to evaluate
the hazard relative to pre-determined threshold levels and decide if it
safe to proceed through an area of concern or to divert. Aircraft
certification requirements will need to be updated to provide for more
ruggedized aircraft health monitoring systems and management processes.
Both flight and maintenance crews will need to know and act accordingly
if an aircraft engine or other vital component has been damaged or has
deteriorated at an accelerated rate that would compromise the continued
safety of flight. Finally, we need to understand if any encounter with
ash might be considered acceptable. This understanding must be based on
rigorous, structured testing and produce reliable and scientifically
quantifiable results. It will never be acceptable to simply see how
close to an ash cloud we can fly and hope for the best.
Mitigate the hazard: Regarding the establishment of an acceptable
threshold for flight near or into known volcanic ash or gaseous
conditions, there are important and applicable lessons learned from the
regulatory and operational experiences that have enabled allowable
flight into known icing conditions. Extensive wind tunnel research,
studies, and flight testing has been done over many years to assess and
certify the safety of flight into icing. Though flight into known icing
conditions is allowed and can be safely conducted under certain
conditions and with specific aircraft anti-icing and de-icing equipment
and appropriately trained crews, icing-related accidents and incidents
still remain an important flight safety issue in the airline community.
As we have learned with icing, mitigating the risk of flight into
acceptable volcanic cloud conditions will not be a quick process but
evolutionary as we learn more about the nature of the hazards. As
testing, research, and development mature enough to establish initial
acceptable threshold levels and to identify the required equipment
changes, new procedures will also be needed.
Government and industry must work together to develop consistent
regulatory and operational guidance and training plans to ensure the
new technologies and information is properly transitioned to the
primary users such as airline dispatchers, air traffic controllers,
mechanics, and pilots.
In conclusion, we have made good progress over the past several
years in monitoring worldwide volcanic activity and alerting the
affected aviation community of an imminent eruption. However once an
eruption has occurred, there is still work needed to better forecast
and standardize information so that hazards associated with drifting
volcanic ash clouds and gases can be safely avoided in flight. ALPA
currently maintains that flights into volcanic ash environments are to
be completely avoided. There is a significant amount of research and
coordination needed to fully understand the hazards, vulnerabilities,
and mitigation strategies to ensure safety is not compromised before we
would support the dispatch and operation of aircraft into areas of
known volcanic ash, even with a pre-determined threshold level
considered to be safe.
Thank you again, for the opportunity to testify on this important
subject.
Biography for Linda Orlady
Captain Linda Orlady presently holds two positions for the Air Line
Pilots Association, International (ALPA). She was appointed as the
Executive Air Safety Vice-Chair in January, 2009 and serves as the
Safety Management System (SMS) Project Director. Captain Orlady is a
member of the FAA SMS Focus Group and the Joint Planning and
Development Office (JPDO) Safety Working Group. She was appointed by
the FAA to serve as one of the tri-chairs for the FAA's SMS ARC
(aviation rulemaking committee).
Captain Orlady has been involved in aviation and human factors for
thirty years as author, researcher, instructor and lecturer. She helped
organize the first International Symposium on Aviation Psychology in
1981 and later served as Technical Chair. She has been a NASA-sponsored
researcher for Yale and Harvard University on a research project
investigating crew complement, procedures and automation. With her late
father, Harry Orlady, Linda co-authored a 600-page book, Human Factors
in Multi-Crew Flight Operations, published by Ashgate Publications in
1999.
Captain Orlady is a third-generation pilot. She received her
initial flight training at the Ohio State University while completing a
Masters in Business Administration with concentration in organizational
behavior and human factors. She flew for several corporations and for
Henson and Comair Airlines in the early '80s. She was hired by United
Airlines as a line pilot in 1985 and has flown the Airbus A-319, A320,
Boeing B-737, and B-747-400. Captain Orlady also worked in United's
Crew Resource Management Department and was the program manager. She
presently flies domestic and international routes on the Boeing B-757
and B-767 out of Washington, DC. She also holds a commercial rotorcraft
rating.
Captain Orlady is the Chair of the Flight Safety Foundation Icarus
Committee and serves on the Board of Governors for the Foundation. She
also serves as a Trustee for the Vaughn College of Aeronautics and
Technology in New York.
Captain Orlady resides in Lothian, Maryland with her husband, John
Cirino, and four dogs.
Chairwoman Giffords. Thank you, Captain.
Mr. Dinius.
STATEMENT OF ROGER DINIUS, FLIGHT SAFETY DIRECTOR, GE AVIATION
Mr. Dinius. Madam Chair, members of the Subcommittee, I am
Roger Dinius, Flight Safety Director for GE Aviation. Thank you
for providing the opportunity to share these observations of
the impact of volcanic ash on engines.
In 1989, we supported the NTSB investigation of a KLM 747
which experienced multi-engine power loss as a result of a
severe volcanic ash encounter over Alaska. In this event,
approximately one minute after the aircraft entered the dense
volcanic ash cloud, power loss occurred. After exiting the
volcanic ash cloud, the engines started and the aircraft landed
safely.
Volcanic ash impacts the engine in three significant ways.
One is corrosion of the compressor blades plugging cooling
holes. It also accumulates on hot parts, deposits on hot parts.
This last failure mode is the least understood and the most
impactful on engine operation. Ash melts as it passes through
the combustor and deposits on turbine nozzles, which can lead
to stalls and subsequent power losses. This is the KLM event.
In the KLM event, ash accumulation on high-pressure turbines'
nozzles led to the engine stall and power loss. The rate of
accumulation from a specific threat is unknown but likely a
function of local volcanic ash concentrations, ash chemistry,
engine design and engine power setting. Compressor erosion and
plugged cooling nozzles or cooling holes are longer-term
deterioration, leading to failure.
In the days following the volcanic eruption in Iceland, GE
issued communications to airlines, the procedures to inspect
and maintain engines post-exposure to volcanic ash. GE
participated in a series of international phone calls dealing
with the volcanic ash crisis. We researched records, relevant
data of the past. We freely shared this information on the
safety matter with agencies, airframers and other engine
companies. The three large engine manufacturers reached
consensus with the FAA and CAA that a no-fly zone would be
established based on a model that predicted volcanic ash
concentration and visible volcanic ash. In addition, a volcanic
ash advisory area with a lower predicted concentration was
established. Operations in this advisory area outside the no-
fly zone would be monitored to determine the impact to engine
operation. We reached this consensus based on industry
experience and engineering judgment.
One quick example. A core engine on a 737-sized aircraft on
hold at 20,000-feet altitude will ingest approximately one pack
of Sweet and Low per minute. This seems like a low amount but
this amount can accumulate as debris and cause engine failure,
leading to premature engine failure. Industry practices have
been to avoid volcanic ash. Such avoidance is made possible by
worldwide weather services, air traffic control and proper
flight planning.
Volcanic ash is a flight safety hazard and can impact
multiple engines on a given flight. Ash has caused failures
within minutes after encounter. GE recommends avoiding flight
into visible ash. If industry is not satisfied with avoidance
as a solution, additional research into two areas is
recommended to reduce risk. The first is volcanic ash
prediction, validation of the models, and the second is to
quantify the impact ash damage has on commercial engines
through controlled experimentation.
Thank you for the opportunity to discuss this with you.
[The prepared statement of Mr. Dinius follows:]
Prepared Statement of Roger Dinius
Madame Chair, Members of the Committee, I am Roger Dinius,
Director, Aviation Safety for GE Aviation. Thank you for providing us
this opportunity to present our views and observations to the
Subcommittee today.
GE aircraft engines and CFM International engines fly approximately
50 million flight hours per year worldwide. Every two seconds, a GE or
CFM-powered airplane is taking off somewhere in the world. At any given
moment, more than 2,200 of these aircraft are in flight, carrying
between 50 and 300 passengers. That's more than 300,000 people, right
now, who are depending on our engines.
In order to appreciate the potential hazard posed by volcanic ash
on commercial aviation, and in particular on aviation gas turbine
engines powering these aircraft, one has to have a basic understanding
of how these engines operate. The modern turbofan engines that power
today's commercial airliners are complex machines that contain more
than 10,000 individual parts. In today's commercial aviation
operations, the engine is expected to remain on the wing for 20,000
hours, or about five years. Therefore, the engines have to be very
reliable while being capable of operating in all kinds of environments.
Each commercial engine is certified to 14 CFR part 33. This
regulation requires specific design characteristic, design analysis,
and testing be completed and approved by the FAA prior to being
certified for installation on a commercial aircraft. There are
currently ingestion requirements for birds, ice, rain and hail, but no
requirement for volcanic ash ingestion. Sand ingestion is no longer a
certification requirement, since effects of sand ingestion are more of
a longer-term maintenance issue and not a flight safety issue
typically. Volcanic ash ingestion is not a certification requirement
for commercial engines. Historically, engines have not been required to
meet a specific volcanic ash threat as a result of the relatively
infrequent encounters.
Before I discuss GE Aviation's experience with volcanic ash
ingestion, a short lesson on engine technology is needed. A gas turbine
engine is comprised of five basic sections: the fan, compressor,
combustor, high-pressure turbine and low-pressure turbines.
The fan brings in a large amount of air from the outside and
pressurizes it. This is either exhausted directly to product thrust,
the force that pushes an airplane through the air, or passes it to the
compressor. The fan is typically made up of a single row of blades
(airfoils--wings) to pressurize the air.
The compressor takes the air from the fan and pressurizes it
further. This compressed air is passed to the combustor. The compressor
is typically made up of 9 to 14 rows of blades (airfoils) to pressurize
the air. Each one of these blade rows contains between 30-76 blades
(airfoils). These compressor blades are aerodynamically shaped for
efficient air pressurization. Additionally the compressor provides air
for cooling hot metal parts in the turbine stages of the engine,
enabling long reliable life.
The combustor takes the air, mixes a portion of it with fuel and
then burns it to increase the temperature of the air stream. Since the
fire in the combustor is so hot, the remainder of the compressors
supplied air is typically used to cool the metal liner of the combustor
and first stage turbine nozzle and blades. Without this cooling the
combustor liner would crack and subsequently lead to a rupture failure,
and engine shutdown.
The high-pressure turbine takes the hot high-pressure air from the
combustor and takes work out of the air stream to drive the compressor.
The high-pressure turbine is comprised of two main components: the
turbine nozzles and turbine blades. The turbine nozzles set the area
behind the combustor to maintain the pressure and turn the air to
efficiently interact with the rotating turbine blades. The turbine
nozzle section is a row of stationary vanes (airfoils). The turbine
blades are typically one or two rows of airfoils that receive the
discharged hot high-pressure air from the turbine nozzles and convert
it to rotational force to turn the compressor. The turbine is like a
waterwheel in operating concept, or a windmill. The high-pressure
turbine operates at very high temperatures, in excess of 2500 degrees
Fahrenheit. At these temperatures the base materials lose their
strength properties, so in order to survive under these conditions and
provide long reliable life, the blades and nozzles are cooled with un-
burned compressor discharge air.
The low-pressure turbine receives the air exhausted from the high-
pressure turbine and takes work out of the air stream to drive the fan.
The low-pressure turbine is comprised of both nozzles and blades
similar to the high-pressure turbine, except the low-pressure turbine
is typically not cooled or cooling is limited to structural frames and
nozzles.
For a jet engine to operate properly and produce continuous thrust,
it is imperative that the air continuously flows from the fan section
and proceed to exit the low-pressure turbine. When this continuous flow
of air is disrupted in the compressor, the engine is said to ``stall''.
To maintain the continuous flow of air it is important that the
airfoils, both stationary and rotating, maintain their shape.
With this understanding of the engine, we can now look at how and
why volcanic ash poses a hazard to aviation. Volcanic ash can hazard an
aircraft if the encounter is of high enough concentration and long
enough duration. There have been a number of engine temporary power
losses due to volcanic ash cloud encounters. GE's first experience with
volcanic ash came in 1989 when we supported the investigation after a
KLM 747-400 experienced a multi-engine power loss while encountering
severe volcanic ash. In this event, approximately a minute after the
aircraft entered a dense volcanic ash cloud, a multi-engine power loss
occurred. After exiting the volcanic ash cloud, the engines restarted
and the aircraft landed safely. The volcanic ash damaged the engines,
causing power loss as well as a permanent performance loss from the
engines. It should be noted that while this is an extreme case, there
are many cases of minor volcanic ash encounters that go unnoticed by
the crew, but contribute to reduced engine on-wing life.
Industry wide experience with the volcanic ash threat has been
acceptable because when aircraft avoid volcanic ash clouds, the
airborne hazards are mitigated. This is a result of worldwide weather
services, Air Traffic Control, and proper flight planning. Volcanic ash
advisories occur across the globe on a weekly basis. Operators respond
to these advisories by avoiding the troublesome area.
Volcanic ash damages engines and can lead to engine failure. The
volcanic ash impacts the engine in at least three significant ways:
erosion of compressor blades, plugging of cooling circuits, and
accumulation on turbine nozzles.
Of these three failure modes, the volcanic ash deposits on turbine
nozzles is the least understood and most impactful on engine operation
as a result of high concentrations of volcanic ash. Volcanic ash can
melt as it passes though the combustor and is then deposited on turbine
nozzles, leading to a reduction in flow area, making the compressor
work harder and resulting in subsequent engine stall (loss of airflow
and thrust). This failure mode was likely the most operationally
disruptive on the KLM 747/CF6 event for which GE has detailed data. In
this event, the ash accumulated on the high-pressure turbine nozzles in
approximately one minute, which led to the engine stall. The rate of
ash accumulation on turbine nozzles in a specified volcanic ash
environment (estimated to be 2 grams per cubic meter in this event) is
unknown and likely a function of volcanic ash density in the
atmosphere, volcanic ash chemical make-up, engine design, and engine
power setting.
The next most impactful failure mode is airfoils erosion. Volcanic
ash, like sand, erodes compressor blades, changing their shape. This
change in shape reduces the efficiency of the airfoil and reduces its
aerodynamic capability to maintain the airflow. Taken to the engines
limit, erosion will lead to an engine stall (loss of airflow and
thrust). Depending on the volcanic ash density in the environment and
particle size of the volcanic ash encountered this can be more severe,
from an erosion stand point, than a sand storm.
The last of the most impactful failure modes is the disruption in
airflow in the hot section cooling circuits. Long life of the turbine
hardware is predicated on maintaining the temperatures within design
limits. As volcanic ash passes through an engine it will find its way
into the cooling circuits and deposit, which results in limiting, or
loss of, cooling flow. This loss of cooling will lead to premature
combustor, turbine blade and/or turbine nozzle failure.
Additionally, volcanic ash contaminates oil systems, air
conditioning systems, erodes flowpath hardware and piping, and deposits
ash in the combustor. While these failure modes are real, and impact
engine operation, they're not typically the most significant failure
modes from a time to failure standpoint when exposed to significant
volcanic ash density. These are expected to be longer-term failure
modes resulting from light to moderate levels of volcanic ash exposure.
The week following the eruption of the Eyjafjallajokull volcano, GE
provided support to our customers to minimize disruptions in service,
and supported U.S. agencies and European agencies to establish safe
guidelines for the resumption of operations in European airspace while
volcanic ash may be present.
On April 14, following the eruption of Eyjafjallajokull volcano, GE
initiated efforts to ensure airlines had information to continue
operations with a volcanic ash threat. The following day, we issued an
update to all operators to inform airlines of procedures to inspect and
maintain engines post-exposure to volcanic ash. Also on that day, the
UK Civil Aviation Authority (CAA) suspended flight operation, due to
volcanic ash in the environment.
On April 16, we received an invitation from the FAA New England
Regional Office to participate in an international teleconference to
deal with the European volcanic ash issue. GE initiated efforts to
understand past volcanic ash events with engines. On April 17 and 18,
we supported additional international phone calls hosted by the UK CAA.
Actual ash concentration predicted based on the UK National Weather
Service (MET) office model for volcanic ash concentration was discussed
and the group worked to establish an appropriate level to prevent a
hazardous environment for civil flights. GE freely shared our
knowledge, observations and experience on this potential safety matter
with agencies, airframers and other engine companies (Pratt & Whitney,
& Rolls-Royce). We researched records to gather relevant data on past
volcanic ash encounters with engines. The UK CAA was acting on guidance
within the International Civil Aviation Organization (ICAO) ``Manual on
Volcanic Ash, Radioactive Material, and Toxic Chemical Clouds'' DOC
9691, which states in paragraph 3.4.8: ``. . . the recommended
procedure in the case of volcanic ash is . . . . regardless of ash
concentration--AVOID AVOID AVOID''.
The group worked to understand the UK MET office model and its
validation. The UK MET office initiated flights to support model
validation. On April 19th, there were further phone calls to establish
consensus on the concentration level of volcanic ash an engine could
tolerate without causing a safety hazard.
On April 20th, engine manufacturers (RR, P&W, & GE) reached
consensus with FAA NE office that flights in volcanic ash would be
acceptable up to volcanic ash concentration levels of up to 2milligrams
per cubic meter and in absence of visible volcanic ash. Additionally
the London Volcano Area Advisory Center IVAAC) would issue volcanic ash
advisories for predicted concentration in excess of 0.2 milligrams per
cubic meter. Operation in volcanic ash concentrations between 0.2 and 2
milligrams per cubic meter and clear of visible volcanic ash would be
monitored to determine the long-term impact on engine operation. This
consensus was based on industry experience and engineering judgment.
GE continues to support regulating agencies and airlines with
volcanic ash inquires, and mature sampling plans. In addition, GE
issued All Operator Wires and Service Bulletins to socialize the
agreement above and to provide guidance for operators on sampling plans
to access longer-term engine impact. In summary, government and
industry working together determined that the Volcanic Ash threat can
be mitigated as long as aircraft avoid visible volcanic ash.
Volcanic ash can pose a threat to safe aviation flights. It has
caused engine failure within minutes of the encounter in severe
volcanic ash cloud environments. Much work still needs to be done to
understand the effects on aircraft gas turbine engines. The
quantitative flight safety risk due to volcanic ash is dependent on a
number of factors, some known and some unknown. These unknowns make
establishing a quantitative limit on volcanic ash a challenge. GE
provided and continues to provide support to our customers and
regulatory agencies to maintain safe operation in light of the recent
volcanic ash threat. The current best practice for abating the volcanic
ash hazard is to avoid visible volcanic ash. GE supports further
research to better define the volcanic ash threat and to establish
working limits, that maintain safe environment for flight and provide
meteorologists a metric to establish a forecast volcanic ash area to
allow ATC and flight crews a known area to avoid.
Thank you again for the opportunity to discuss this issue with you.
Chairwoman Giffords. Thank you, Mr. Dinius, and thank you
to all of our witnesses today. I honestly don't think we could
have assembled a more senior expertise and really diverse group
of witnesses to an issue that is very important. And of course,
what strikes me is, as Mr. Olson said in his opening comments,
that really not since 9/11 have we had such a large disruption
in air traffic. We have yet to have any fatalities or
catastrophic incidents associated with volcanic ash but the
possibility is great and our job here on the Subcommittee is to
make sure that we are doing everything we can so that we have
the research and the information to keep air travelers safe, to
keep airlines running and to make sure that we can have the
information also to explain it to passengers and to the general
public as well.
Characterizing the Risk
We are going to begin our first round of questions, and the
Chair will recognize herself for five minutes.
I would like to begin with Captain Orlady. Speaking of
expertise, she is a third-generation pilot, which is
tremendous, and as I said when we had a chance to meet before
the hearing, those of us who commute here to Washington every
week feel like we have a very close relationship with all the
pilots and we have a lot of trust in the FAA and other
organizations that of course keep us safe as well as obviously
the general public. But Captain, you indicated in your written
statement that the dilemma is that currently we do not have
scientifically reliable and valid data which tells us how we
might--how that might be accomplished in terms of the need for
research and development. So I was hoping that you could and
then the other members as well, if you could talk about the
research that you feel is needed to better understand when it
is safe to fly through airspace that has been contaminated with
volcanic ash and is there a way to characterize the risk of
flying under such conditions?
Ms. Orlady. Thank you very much, Madam Chair, and I
appreciate your business and the confidence you have in the air
transportation system because we work hard and it is a process
to keep working with that.
There is not an acceptable level of contamination right
now. Part of the dilemma I think is twofold. One, we don't
get--we do not receive, rather, good real-time data. There is
data that is collected, and these folks, my fellow panel
members can talk much more precisely about it than I can, but
there are models that are interpreted. There are different
models that are used. Even if they are using the same model,
there are different interpretations that are used, and in fact,
my husband made, I think, a good analogy last night when we
were talking about this as I was driving through some DC.
traffic and looking at a display. He said well, that is not
real-time data so just go ahead and plow through even though it
is red. We can't do that up in the air. You know, if you don't
like it on the beltway, you pull over and park or something
else perhaps but you can't do that airborne. We cannot afford
to take that risk so we don't get good real-time data as well
we don't have a high level of confidence. It has gotten much
better but in terms of the forecasting methods, in terms of are
we all talking on the same terms, with agreement on the same
terms and understanding as to what they mean.
So I don't mean to seem a little bit skeptical with that
but at this point there is no acceptable level of contamination
that we think we know enough about to accept. I wish we did,
given how the economic problems that we had with, as my partner
here suggested with the big E volcano because it was quite
disastrous.
Chairwoman Giffords. And in terms of characterizing the
risk of this, can you put it in layperson's terms of--I mean,
we have heard a lot of information, but as a pilot, with all of
us in the cabin, I mean, how do you quantify that?
Ms. Orlady. This would not be that difficult. So you have
your power plants, your engines. They potentially stop working.
You become a glider. Your windshield can be very quickly
eroded. In fact, one of the procedures I have seen from one of
our member airlines mentions specifically if the windshields
are eroded, consider diverting to an airport where an auto land
can be made. This does not exactly make your day. Then you have
what sort of things are you breathing, you know, in terms of
this and how much do we really know about it in terms of the
itchy eyes, in terms of breathing difficulties. There is
nothing about this that sounds appealing. If it was just one
item, one factor, maybe we would do that. Maybe we will have
engines that will be able to withstand some of this. That would
power plants, that would be good, but we have so many other
issues and aircraft systems that are affected that we really do
not understand. I think of all of the ramifications. We have a
learning to do. But mostly for passengers and certainly for
pilots, no interest in kind of going there. There are just too
many things that kind of go wrong, and heaven forbid not being
able to see out the windshield to land.
Chairwoman Giffords. Thank you.
Would others care to comment?
Mr. Kaye. I will just comment briefly then. In terms of one
of the real challenges is both having the observations and the
models. For NASA as a research organization, the satellites can
overfly a particular volcano at a regular time based on durable
mechanics. There are other satellites that NOAA as an
operational agency and particularly has used geostationary
satellites that do get enhanced temporal coverage, but you can
only--for most of the satellites that we have, we can only
overfly them in a certain time period but we can use models to
help. We can initialize models and the data can help evaluate
them and improve them for the future.
Chairwoman Giffords. Thank you.
Mr. Olson.
The European Response
Mr. Olson. Thank you, Madam Chairwoman. I don't know if you
all had an opportunity this morning to see there was an article
in the Wall Street Journal this morning, and let me read the
headline: ``E.U. ministers to speed up talks on aviation
rules,'' and there was just one little paragraph here that I
thought was pretty appropriate for what we are taking about
today. ``The 27 ministers also agreed that there is a need to
urgently come up with limits as to how much ash is dangerous
for the airplane engines,'' and so sort of taking up on that
and following up on some of the comments you made, Mrs. Cox, in
your opening statement, how would you characterize--this is a
question for all of you but how would you characterize the
European Civil Aviation Authority's response to the Icelandic
volcano? I mean, was the breadth and duration of the shutdown a
sensible approach based on sound science? Was it kind of a
play-it-safe reaction because of a lack of scientific
knowledge? And also, just sort of want comments on what was the
impact of a balkanized air traffic control system here?
Ms. Cox. So I don't want to second-guess the Europeans'
decision to close the airspace not having been there with the
actual data that they were looking at. I will say that
certainly the geographic layout of Europe probably contributed
to their decision. In the United States, we largely handle
volcanic ash by routing around it. Their particular situation
probably prohibited their ability to do that. So that was a
contribution. But certainly there is no known level of volcanic
ash that is known to be safe to fly through.
And as I mentioned in my testimony, the fact that there
were 27 civil aviation authorities who had to contribute to the
decision probably contributed to the difficulty in once the
decision was made in deciding what to do about resuming flight.
Mr. Olson. Captain Orlady, any comments?
Ms. Orlady. I agree with Ms. Cox. I am not sure--Europe has
some different challenges that I think they handled very, very
well most of the time but we handle things a little bit
differently. We have a little bit more airspace here so it is
difficult, you know, when one is going to the other and you
want to be safe, but basically I agree with everything Ms. Cox
has just said.
Mr. Olson. Any other panel members want to comment on that
issue? Okay. We will take that as a big no.
Coordinating Research Among Agencies
All right. Dr. Kaye, the next question is for you then.
This is about coordinating research among the Federal agencies.
It appears that other operational agencies are heavily reliant
on NASA-provided data to enable their own capabilities to
characterize, measure and forecast volcanic ash cloud
movements. To what degree are research efforts being
coordinated among Federal agencies to develop future sensor and
modeling products?
Mr. Kaye. Well, there is an interagency coordinating effort
carried out under the auspices of the Office of the Federal
Coordinator for Meteorological Services and Supporting
Research, so I think that deals with some of these kinds of
things on a regular basis. In the longer term, there is any of
a number of ways in which we will work together to help develop
plans. Some of the things that we are trying to do at NASA,
especially as we look towards the future and some of the future
missions, those that have been identified by NRC and the
decadal survey is to bring the users into the mix as early as
possible so, for instance, one thing that we did this past
February was hosted, we call it essentially an applications
workshop between our Applied Science program and our Flight
program so that we could have a way for those who would be
potential users of the data that we would be able to provide
with the next generation of satellites talking with us so we
better understand what their needs are and the relationship
between what we can provide and what they do need. So those
kinds of conversations, especially for NASA, bringing people,
potential users in at an early stage helps us understand and
potentially tailor things where it makes sense. For instance,
one of the--the HyspIRI mission, which is a SO2
decadal survey mission, some of the wavelength bands are
specifically chosen to provide information on volcanic
SO2.
Mr. Olson. Thank you very much. Just in closing, I would
like to make a statement. I mean, it is pretty clear to me that
we need to develop onboard equipment and a thorough
communication network, so as Captain Orlady said, the pilots on
board the traffic can get real-time information about any
volcanic ash activity. I mean, the only thing that is going to
be 100 percent safe is avoidance, and I was in the Navy, a P-3
pilot. As a young patrol plane commander, I made a mistake and
we are coming home after an 8-hour mission about 4:00 in the
morning, had some get-home-itis and we had a radar on board
that wasn't weather certified but guys kind of made guesses and
they said we have got a thunderstorm here in front of us, Mr.
Olson, it is about 10 miles wide. I am big and bad, I am a new
patrol plane commander, all-weather aircraft, we will just
punch it through, guys, rather than spend another 45 minutes
going around it. We punched it through. We got through fine.
The lightning bounced off the aircraft. That is very
uncomfortable. You know you have gotten yourself in a position
you shouldn't be in, and, you know, I threw the people around
on the aircraft for a good three, four minutes and that was
completely unnecessary. And of course, when I got back to the
ground and had to deal with 11 crew members walking around,
``Oh, Mr. Olson, my back, it's so sore.''
The point of it is, is we got to get them the information.
If I had had the information and seen how dense that cloud was
when we punched through it, I would have never done it. I would
have gone around it and we would have been 100 percent safe.
Same thing with volcanic ash. If we avoid it, if we get the air
crews the information they need to that aircraft, they will
make the right decision every time.
Thank you, Madam Chairwoman.
Chairwoman Giffords. Thank you, Mr. Olson.
We are going to hear now from Ms. Kosmas.
The Use of Simulations for Training
Ms. Kosmas. Thank you, and thank you all for being here
today. I happen to represent the central Florida area which has
the National Center For Modeling and Simulation, which is in
Orlando, and that develops the simulator tools that are used to
increase skills, mostly in my area for the military at this
current time but of course all of that information leads to
simulation that helps us in nearly every scientific endeavor
that we are working on these days.
Captain Orlady, you had discussed the use of simulators by
American Airlines in training their crews to provide them with
advanced training in the event of ash cloud exposure, and so I
was curious whether you or any of the other members could
discuss the use of simulators for advanced training for crews
in this type of situation and whether it can or should be
incorporated into crew training universally?
Ms. Orlady. Thank you very much, and just for the record,
it is Alaska Airlines rather than American that----
Ms. Kosmas. Oh, I am sorry.
Ms. Orlady. --that had that, and as you might imagine,
because they have the chance to--their exposure rate is quite a
bit higher. I have talked to in fact a captain 2 days ago who
had just been through some recurrent training, and recurrent
training at the airlines, as you may know, will have different
things every year. Wouldn't you know this year they have some
scenario for volcanic ash and inadvertent entry? Obviously this
was planned well before Iceland decided to kind of get active
so the timing is quite curious. It can be very effective in
terms of putting you through the scenario and the checklists
that we have and seeing how it works, and I am reminded from
talking with him and your question, one of the symptoms also
that I did not mention or potential consequences, all the
avionics we have in today's aircraft, the radios, navigation
radios and particularly with the newer generation aircraft,
they needed to be cooled just like our computers at home. They
don't get the cooling of the airports if you will, our cooling
ports are blocked. They do not-desirable things. They blank and
they just kind of disappear. So that isn't very helpful.
So it is very good with training scenarios. The high-
fidelity simulators that we have do allow a high degree of
realism. It is helpful to do it and it is good to go through it
and I think it certainly sends home the message quite loudly
that you do not want to be in this air and don't try be a P-3
trying to get home kind of quickly so you can be done with it.
It is just, you know, not worth it. So the simulations can be
very good although the message at least for us right now is,
you don't want to get in this, it reinforces. Thank you.
Ms. Kosmas. Thank you. I appreciate that.
Does anyone wish to comment on that particular question?
Obviously the desire is not to be there but should the occasion
come up where someone is, the ability to be prepared and to
make the right kinds of decisions is helped, I think, by early
training and simulation training.
Thank you very much.
Chairwoman Giffords. Thank you, Ms. Kosmas.
Mr. Rohrabacher.
Engine Design
Mr. Rohrabacher. Thank you very much, and thank you, Madam
Chairman, for calling this hearing. It is obviously of great
interest to the overall public and to those of who travel every
week on jet airplanes. I flew in last night. I would like to
identify myself with the statement by Ranking Member Olson, who
put this in perspective in terms of threats. What we have here
is a threat that rarely is confronted, but when we do confront
it, it becomes something of utmost importance because it could
result in a tragic loss of life, and we hear this argument a
lot on Near-Earth Objects. I mean, the chance of a meteorite
hitting the earth, what is that. But of course if it does, it
could kill hundreds of thousands if not millions of people, so
these are the threats that we need to pay attention to.
Unfortunately, and how that relates to our committee, is that
research is skewed or at least directed towards threats that
are a little bit more frequent than these threats that don't
happen very often, but when they do happen, they pose a great
danger.
Let me ask, is there any--first of all, Mr. Dinius, your
Sweet and Low package, you are saying that that much debris in
a jet engine could actually bring down a plane?
Mr. Dinius. Okay, so to clarify. No, sir, it will not.
Mr. Rohrabacher. Okay.
Mr. Dinius. That was just a particular example for a one-
minute time. If that same kind of concentration were to be
taken, for instance, from London to Paris and back on five
trips a day, you are talking multiple pounds of contaminant
that can get in the engine to either deposit on turbine blades,
plug cooling holes and potentially lead to failure.
Mr. Rohrabacher. And right now is there any research
efforts going on that would--with your company or that you know
of in the Federal Government that is taking this threat into
consideration in terms of jet engine design or is this
something that is just not being addressed now?
Mr. Dinius. Sir, from a very obvious standpoint,
contaminants in the engine and the small cooling holes in these
parts, the reality is, we have to keep those clean for long
life. We expect these engines to stay on wing for 20,000 hours,
five years. Flying through this type of debris shortens the
life of the engine, could lead to failure. It is a cumulative
thing. You know, you fly through it----
Mr. Rohrabacher. Do you know of any efforts or is there
anyone looking at this and saying here would be an engine
design that would be less susceptible to that?
Mr. Dinius. Not that I know of, sir.
Mr. Rohrabacher. Anybody else know of any research like
that? Again, this might be one of those instances where because
the threat is not frequent, that we are paying attention to
other threats rather than this and it may be worthy of us
looking into that.
Mr. Olson's experience in terms of cloud density, let me
just ask, when we are talking about cloud density, Mr. Olson,
that turbulence that you experienced, did that affect the
engines of the plane or is it just the other dynamics of the
plane?
Mr. Olson. It did not affect the engines on the aircraft. I
mean, the big problem that I encountered that I didn't
appreciate was the fact that the equipment on board my aircraft
wasn't weather radar and it was an operator who could make
guesses, and I took that as something, okay, we can punch
through this and decided to punch it through, but it was not
anything that damaged the aircraft.
Mr. Rohrabacher. So the research that we are talking about
might--if there is a research and a scientific solution or
something that would help might take in, for example, research
into radar and that would then--or methodology of determining
density of what people are flying into, the density of the air,
the clouds, et cetera. What about materials research? Mr.
Dinius or anyone else who would have this, is there something
that we could do in terms of the materials that engines are
made out of or is this simply the design of those engines?
Mr. Dinius. I am not aware of any material work that could
be done to avoid this at this point.
Mr. Rohrabacher. Any other thought on that? This is a
materials issue then, it is an actual design issue. Well, thank
you very much for your testimony.
Madam Chairman, again, thank you for putting together an
expert panel for us to enlighten us on this issue, and I have
gotten a lot out of this. Thank you.
Chairwoman Giffords. Thank you, Mr. Rohrabacher.
Now we are going to hear from Ms. Edwards.
European Consultations
Ms. Edwards. Thank you, Madam Chairwoman, and I will tell
you, for weeks I have been dying to say, what is it,
Eyjafjallajokull or something.
My question actually, Mr. Dinius, goes to you. Was GE
Aviation consulted by the Europeans before resuming flights,
and was NASA's DC-8 experience taken into consideration in that
consultation?
Mr. Dinius. So yes, we were invited to participate in a
series of teleconferences with the FAA and the CAA over the
weekend that followed the eruption in Iceland. We took into
consideration the data we knew of, the DC-8 NASA, we knew of
that one. There are other events that we have data from. It
should be pointed out that the DC-8 event NASA had was not an
engine failure, it was an economic impact but not an engine
failure.
Detecting Contaminants
Ms. Edwards. And I guess I am curious, on the ground like
in testing engines, because you have to do some kind of cost-
benefit analysis, I mean, it is not as though aircraft are
flying through volcanic ash all the time, although it is
significant. How do you actually--how would you design and test
an engine for whatever level of volcanic ash would be
acceptable?
Mr. Dinius. Ma'am, there is no certification requirements
today for sand and dust or volcanic ash. However, you could run
engineering tests or you can control the level of contaminants
that are put in the engine and then see how the engine responds
as well as look at the engine afterwards to see its condition,
its health.
Ms. Edwards. And over time, you could have a number of
given contaminants that might impact an engine or other
aircraft parts so you might know on a first run, for example,
on one flight it might be sand, depending on where that flight
is going. On another flight it might be volcanic ash. I think
what the discussion hasn't come to is, what combination of
those things, even if it is not one or the other, is there a
combination of those kind of environmental materials that
really could contribute to engine failure and measuring one and
not the combination might not tell you very much about whether
the aircraft could travel safely?
Mr. Dinius. So the chemical constituents inside the
volcanic ash make a difference on the failure modes. The
melting point of the contaminant, the volcanic ash, make a
difference. If it doesn't melt, it is not going to stick to the
turbine blades. It may erode them but it won't stick to them.
So that is a different failure mode than your classic sand and
dust. We have good history with sand and dust. We understand
how blades erode. With volcanic ash, the data is fairly sparse.
Human Factor
Ms. Edwards. And Captain Orlady, one of the things that you
pointed to was the fact that, you know, so for example, with
volcanic ash, for one pilot it might result in itchy eyes, for
another it might result in not being able to see out of a
windshield where some other pilot actually might be able to see
out of that windshield but wouldn't have itchy eyes, so there
are a whole number of human factors that one couldn't possibly
account for. I guess what I am getting to is that when the
question becomes do you shut down an entire system or not, I
think it is very hard to measure the point of your testimony
that you get to which is do you really want to take that
chance. I mean, it is a huge economic cost but it may be better
to shut down the system because you could never really account
for the factor or other human or mechanical that could
contribute to a failed flight.
Ms. Orlady. I think that is an accurate perception. It
really is a multi-pronged problem. The questions that were
asked of Mr. Dinius about the engine, perhaps----
Chairwoman Giffords. Captain, your microphone.
Ms. Orlady. I pushed it. We will put it closer. But it is a
multi-prolonged problem because let us say we determine
something with the engines and maybe we do--but that just
doesn't solve the avionics that still need to be cooled. It
still doesn't solve the windshield that if I can't see out of,
even if I don't have breathing difficulties and itchy eyes, if
I can't see out of it, then it doesn't make much difference. So
I wish I was more optimistic but I think your description is
correct in terms of looking at the severity, potential severity
and consequences. We don't have much choice until we get better
data at this point.
Ms. Edwards. Thank you, Madam Chairwoman.
Chairwoman Giffords. Thank you, Ms. Edwards.
We are going to have a second round. We have got a couple
of follow-up questions that would like the panel to answer.
Following up on Mrs. Edwards' point about the DC-8, with us in
the audience we have Mr. Thomas Grindle, who is a propulsion
engineer, and I was hoping that he could come up to answer a
couple of questions. Thank you, Mr. Grindle.
NASA DC-8 Experience
A report that you wrote indicates the pilots did not notice
anything out of the ordinary after flying through volcanic ash
clouds. After landing, could you talk about what parts of the
aircraft that you did look at and did any other aircraft
besides yours go through the same areas and did they also reach
similar no-problem conclusions?
Mr. Grindle. Thank you, Madam Chairwoman. Yes, once we--the
scientists on board were the ones that alerted the flight crew
that we were currently flying a diffuse ash cloud from the
Hekla volcano. The pilots noticed no onboard indications
whatsoever. Engine parameters were normal. No smells in the
cockpit. Because it was night, we looked for the St. Elmo's
fire. No indications whatsoever. The scientists were the only
ones because of their instrumentation on board to notice that
we were flying through the cloud. The incident lasted for about
seven minutes, and the aircraft continued on to Sweden.
Once there, they contacted us back at NASA Dryden and asked
about, you know, what they should and we recommended to do a
complete visual inspection on all the leading surfaces of the
airplane, the windshield, the leading edges, to look at the
engine fan blades, engine cowls, anything that could have had
any abrasive damage or anything. They performed those
inspections, found no damage whatsoever. Our recommendation
from Edwards was to then replace the air conditioning filters
and the engine oil on all four engines and hold samples for us
for once they returned back to NASA Dryden. They flew for about
68 hours in Sweden doing other atmospheric research missions
and returned back to Dryden where we were able to do a complete
engine borescope on all four engines and there we noticed some
clogged cooling holes and abraded leading edges on the turbine
section. We removed one of the engines, which was getting close
to an overhaul maintenance requirement, and sent it to the
engine manufacturer in Strother, Kansas. They tore it down and
found more damage inside. We then removed the other three
engines and sent them to the same manufacturer as well, and
upon those teardowns they found more of the same contaminations
inside and the same damage listed in all four engines.
Chairwoman Giffords. Mr. Grindle, can you talk about the
lessons learned from this experience? What are the key take-
aways for us that we should be focusing on, and in your view,
from all the knowledge and information that you have gathered,
are these lessons actually being applied today?
Mr. Grindle. I can only speak about the DC-8 incident which
we had, and prior to us leaving Edwards we knew about the
eruption and so we purposely made our course as far north as
possible, and in fact on the way over we added another 200
miles, so I think our total distance from the volcano was
almost 800 miles, and at the altitude and the latest
information we had gotten from the London Volcanic Ash Advisory
Center, we were well north of any kind of ash cloud whatsoever,
and upon the engine teardown and the scientific data
evaluation, some of the particles we flew through were less
than one micron in diameter, and even at those limits, we
didn't experience any engine parameter failures or any
indications whatsoever but the engine manufacturer who did the
work specified that we probably would have started seeing
performance degradation in some of the engines in as little as
100 flight-hours because of the loss of cooling and other
things.
And as far as I know, we were the only aircraft to fly in
that area through the ash cloud, and once we did realize we
were in it, we updated the London center and told them that we
had experienced it in that area and they were able to update
their predictions in those areas as well.
Chairwoman Giffords. Thank you.
Mr. Grindle. Thank you.
Detection Systems
Chairwoman Giffords. I have a follow-up question for either
Dr. Strazisar or Dr. Kaye, and this builds on Mr. Olson's
comments about having an onboard display. How far away are we
technologically speaking or even from an implementation
standpoint from a cost perspective for an onboard volcanic ash-
type detection system that ALPA was talking about in terms of
really giving the pilots the information that they need? I am
curious, I mean, do we know how to build them and do we know
when we will have them?
Mr. Strazisar. We are in our aviation safety program
working constantly on instrumentation that is forward looking,
primarily to provide better indications of weather because
convective weather is actually on a probability basis a much
greater problem than volcanic eruptions. Some of those forward-
looking systems have the potential to detect ash but that is
not their primary purpose. So we are continuing to do research
on constantly improved instrumentation. We will keep our eyes
open in the future for any technologies that would have a side
benefit of being able to also detect ash, but we are not
working currently on any system specifically to detect ash.
Chairwoman Giffords. Ms. Cox or Mr. Dinius or Dr. Kaye, any
additional--because Captain Orlady is looking a little nervous,
so maybe wants some reassurance that we are working on this
technology.
Ms. Cox. I can comment on some of the work the FAA is
investing in with our NextGen research and our NextGen
programs. While we are not focusing on onboard sensors on
aircraft, we are focusing on delivering better information to
the pilot, to the controllers, to the airline dispatchers so
that they would all have the same information in real time that
they could use to make better decisions collaboratively about
how to proceed in these conditions. Reports--there was a very
good report done by NOAA after the Mount Redoubt eruption in
2009. It was just published this January, actually. And they
published best practices and findings and recommendations.
Overall, one of the best practices was web-based communications
that they had during the Mount Redoubt eruption. Findings and
recommendations focused in large part around better
communication and better collaboration, so this is where our
focus is.
Chairwoman Giffords. Anyone else?
Mr. Kaye. I think what I will have to do is to take an
action to try to get additional information and report back,
especially as to what precisely the sensors were that were
aboard the DC-8. I don't know if we know exactly what they were
doing that provided us some information, whether they were in
situ measurements that actually made air sampling in the
vicinity of the aircraft or remote sensing kinds of things. It
is an answerable question. I just don't have that. If it is in
situ, of course, then that becomes an issue because then you
essential have to have a detector which if that involves
cutting a hole in the plane, that is a whole separate set of
issues for that, and if it is a remote sensing thing, then you
have to find out, you know, radar is--for very small aerosol
particles, radars typically don't work. That is the way we do a
lot of optical wavelengths and LIDARs, but I will have to get
back to our people and find out specifically what the
instrumentation was that detected that and then see whether
that is something that potentially would be applicable or not.
Chairwoman Giffords. We would appreciate that, Dr. Kaye, if
you could report back to the Subcommittee. Obviously we are
interested. This is a timely hearing, and you know, the general
public is also very interested. You know, we hadn't focused on
this for many years but with this eruption certainly it was all
on our radar screens.
Mr. Olson, do you have any follow-up questions?
Mr. Olson. Two more questions. Home stretch.
Future Remote Sensing
The first one is for you, Dr. Kaye. You outlined a number
of instruments found on orbital NASA research satellites that
have been key towards helping understand the composition
physics of volcanic plumes. What is the future of doing these
kinds of capabilities from space related to what is the
likelihood that NOAA or the USGS will be able to absorb these
capabilities into their own operational systems?
Mr. Kaye. A number of the sensors that we have and the
satellites that we have are past their--what we call their
prime life period. They are in extended operations. But thanks
to good engineering, we can nurture these things for quite a
while, the satellites, for a very long period of time. There is
some evolution that is planned, future satellites that we have
planned, the Glory satellite, which is specifically designed to
measure aerosols using polar metric technique, so that will add
significantly to our body of knowledge because those
observations will help provide information not just about
aerosol presence, where something is, but what something is,
which is very important as well, especially for initializing
models.
For including a lot of the optical infrared observations
that are done through our modus instrument, the NPP mission, we
will do the launch in 2011, we will continue those, and that is
a precursor to the Joint Polar Satellite System, which will
provide enhanced operational capability into the future.
There are some other things that we do that there is no
sort of near-term plans but people look at in the long term. We
use multi-angle viewing with the MISR instrument that looks in
nine different directions and helps provide information about
altitude, composition. One of our decadal survey missions, the
ACE mission would use multiple-angle techniques but that one is
further out into the future, and one of the neat things that we
have right now is the Calypso. It is a LIDAR-based measurement
which can get very accurate and very precise information about
thin layers. It looks straight down but it is an optical
equivalent of radar so you can see very thin layers and know
precisely what altitude they are at. That has been flying since
2006, and we don't have--the next LIDAR I think that we will be
looking at for aerosol purposes would be also the ACE mission,
which is one of the DOD decadal survey missions.
One thing I can say is that for a lot of these things we
don't have to go it alone. There is a good record of data
sharing with our international partners to the extent that the
Europeans will do things or the Japanese will do something, the
Europeans in particular I think are looking at LIDAR missions.
So we will have some opportunities there.
You mentioned U.S. Geological Survey. I haven't talked
about them. They have the primary responsibility for surface-
based measurements, especially about what is going on and at
the surface of volcanoes, so that is a different kind of thing
than what we normally do. We work with them on land cover
observations as well and that is a good relationship.
Priorities
Mr. Olson. Thank you very much. One last question, and I
don't mean to put words in your mouth but given the constrained
spending environment we are dealing with up here, if we had to
prioritize our efforts going forward, what do you believe makes
the most sense? And I think the group, if I could summarize,
and if you disagree with this, please hit the button and chime
in. But I think the first priority should be developing
technology both on board and within the aircraft tracking
system, get real-time information to the pilots as these
volcanic plumes developed. The second priority should be
develop a better understanding of engine performance and
degradation, and the third priority should be trying to harden
the engines and make them where they can fly through things
that they probably can't fly through now. And again, to me that
seems to be the consensus here of our priorities going forward
with our limited dollars. If anybody has a disagreement with
that, I would certainly like to hear it. All right. Amen. Thank
you very much.
Chairwoman Giffords. Thank you, Mr. Olson. Before we bring
this hearing to a close, I want to thank all of our witnesses
for being here. We have just scratched the surface today. The
Subcommittee hearing is timely. Obviously your expertise is an
asset and a real value to the Congress, to the American people
and to the international community as well. So we look forward
to any additional information that you would have for us,
updates of course we would welcome, and thank you for taking
time out of your busy schedules to be here, and Mr. Grindle as
well, thank you for coming in from California. We very much
appreciate all that you do to keep our skies safe. We sincerely
appreciate it. And again, as mentioned many times, this is an
unusual incident but the potential of catastrophic loss of life
and risk to the airline industry is great, so we appreciate
particularly Captain Orlady. Again, I think because all of us
commute so much, we really feel like we have a personal
relationship with all of our pilots, so appreciate everything
you do on behalf of all of our airline pilots and of course all
the flight attendants and everyone who we, you know, spend a
lot of our time with as well.
The record will remain open for two weeks, so if there are
any additional statements from members and any answers to any
of the questions that we would like our witnesses to follow up
on, please submit that for the record.
The witnesses are excused and the hearing is now adjourned.
Thank you again.
[Whereupon, at 11:23 a.m., the Subcommittee was adjourned.]
Appendix:
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Answers to Post-Hearing Questions
Answers to Post-Hearing Questions
Responses by Dr. Tony Strazisar, Senior Technical Advisor, Aeronautics
Research Mission Directorate, National Aeronautics and Space
Administration
Questions submitted by Chairwoman Gabrielle Giffords
Q1. It is clear that from the difficulties European aviation
regulators experienced while deciding when to reopen airspace, some
fundamental data was missing. Yet, the negative impact of flying into
volcanic ash clouds has been demonstrated. And, thanks to NASA, we have
been warned that engines may not show signs of damage until after 100
flying hours. So why do you think there hasn't been greater focus on
this area by the world's aeronautics research community? What research
needs to be performed?
A1. We believe there has not been greater focus on the issue of
commercial aircraft operations in and around volcanic ash clouds
because an event such as the recent eruption in Iceland is rare.
Hazardous weather conditions such as convective weather (thunderstorms)
and icing pose daily disruptions to commercial air traffic around the
world. As a result, the aviation community has focused research and
development efforts on the development of capabilities such as airborne
and ground weather radar, air traffic re-routing procedures, and
aircraft icing protection systems. Satellite assets are capable of
detecting volcanic ash clouds, but the dispersion of the cloud and the
concentration of ash are difficult to accurately predict with current
weather modeling capability. Research leading to improved prediction of
ash cloud extent and ash concentration within the cloud would enable
more accurate air traffic re-routing to avoid flying into airspace in
which ash concentrations are unacceptable.
Q2. What technology is needed such that aircraft can have onboard
warning of volcanic ash conditions? What research is needed to develop
and demonstrate that technology? Who should perform such research?
A2. Technologies capable of detecting small-diameter particles
suspended in the atmosphere are required if onboard indication of
volcanic ash conditions is desired. Although techniques such as Cloud
Physics Lidar and Visible Infrared Imaging Spectrometry are available
for NASA research aircraft, it would be prohibitively expensive to
equip the commercial aircraft fleet with such capability. NASA
continues to develop capability for airborne forward-looking sensing of
atmospheric hazards. This research is looking across a suite of state-
of-the-art sensing technologies that have potential to detect various
hazards types, which could include volcanic ash. Improvements in
technologies such as LiDAR (Light Detection and Ranging), FLI (Forward-
Looking Interferometry), and X-band radar hold potential for detecting
volcanic ash and aiding pilots to determine the safety of flight
through volcanic ash areas. Current NASA aviation safety research on
LiDAR seeks, encourages, and emphasizes the ability to detect multiple
hazards (which to date have primarily included icing, wake turbulence,
and limited visibility). Some current research, such as the forward-
looking interferometer research, has looked at volcanic ash detection
capability. NASA will continue to support the development of sensing
technology capable of detecting multiple hazards, including volcanic
ash. This month EasyJet airlines announced plans to test a system
consisting of two infrared sensors carried in a plane's tail fin http:/
/www.guardian.co.uk/world/2010/jun/04/easvjet-volcanic-ash-radar. The
system, developed by the Norwegian Institute for Air Research, has the
potential to detect volcanic ash particles up to 62 miles ahead of a
plane's flight path.
As an alternative to onboard ash detection, research leading to
improved forecasting of plume location and ash concentration would be
beneficial. Improved plume prediction models would enable the Volcanic
Ash Advisory Centers (VAAC) to pass more accurate information through
the aviation advisory capability of the aeronautical fixed services
operated by the Federal Aviation Administration so that plume location
information could be used for flight planning for plume avoidance. The
NASA Science Mission Directorate testimony outlined several improved
modeling activities.
Q3. It is probably impractical and uneconomical to design a jet engine
that can withstand all volcanic ash conditions. From what we know about
aircraft engines, aviation safety, and the economics of the airline
industry, what is the best that we can expect from future engine
technology improvements?
A3. The most immediate effect on a modern aircraft engine of ingesting
volcanic ash is the melting of the ash in the hot section of the
engine. The ash then forms glassy deposits that alter the airflow
through the turbine blades downstream of the combustor. Continued
buildup of these deposits can restrict airflow through the engine and
cause the engine to stall. In several well-publicized incidents, engine
stall has occurred in a matter of minutes after passing through severe
concentrations of ash. In addition, volcanic ash can clog the cooling
holes and damage the thermal barrier coatings which are used to protect
the turbine blades from combustor exhaust temperatures that exceed the
melting point of an unprotected blade. This reduced thermal protection
can over a longer period of time reduce the remaining safe life of the
turbine components. To increase cycle efficiency and reduce fuel bum,
future engine technology is pushing toward ever-increasing combustor
exit temperatures, which will only exacerbate the problems caused by
melting ash and reduced cooling system performance. There is current
research on adaptive engine technology being performed under the DOD
Versatile Affordable Advanced Turbine Engine (VAATE) initiative. This
research is developing technology to enable gas turbine engines to
alter their operating mode to adapt to varying mission requirements.
Once these technologies are demonstrated for military applications they
may find their way into commercial applications and could enable an
engine to re-configure its operating conditions in response to the
accumulation of ash deposits and a reduction of cooling flows to
turbine components. This technology is several years away from reaching
a maturity level at which it could be included in new commercial
aircraft engine designs.
Q4. Captain Orlady indicated in her statement that Alaskan Airlines
has developed extensive classroom and scenario-based simulator training
that provides crews with effective tools and techniques that can be
used in the event of inadvertent airborne ash cloud exposure.
Considering NASA's unique expertise in human factors in aviation, is
there value in more focused research on developing technologies that
can simulate volcanic ash conditions to pilots and crew?
A4. There is value in educating pilots and crew in proper procedures to
follow in the event that an unintended encounter with a volcanic ash
cloud impacts engine performance. However, it is not clear that any
additional research on simulating ash conditions is required. In the
late 1980s and early 1990s, research on the effects of dust ingestion
on gas turbine engine performance was led by Dr. Michael Dunn at the
Caispan Corporation in Buffalo, N.Y. Dr. Dunn is currently at Ohio
State University. Dr. Dunn used volcanic ash as a source of dust during
those investigations. In the course of that research, Dr. Dunn
discovered that glassy deposits of volcanic ash that accumulated on the
surface of turbine blades could be cleared by reducing engine power to
idle and then returning to a cruise throttle setting. During the brief
return to idle the turbine blades cooled and shrank slightly, causing
the glassy ash deposits to break off. This finding was incorporated in
a flight crew briefing video created by the Boeing Company in 1992,
Volcanic ash avoidance--flight crew briefing: Boeing Commercial
Airplane Group, Customer Training and Flight Operations Support, which
is available as Video 4V703 from the International Civil Aviation
Organization (ICAO). The video discusses what pilots and airline
dispatchers can do to avoid volcanic eruption clouds, and the
recommended steps a pilot should take in the event of an unexpected
encounter. This training video also shows how volcanic ash can affect
jet aircraft and provides a pilot's first-hand account of an incident
in which a Boeing 747 encountered an eruption cloud and temporarily
lost power in all four engines. ICAO provides translations of the video
into French, Russian, and Spanish. Presently, neither that video nor
other volcanic-ash information developed by airframe and engine
manufacturers is mandated for inclusion in training material for
pilots. http://volcanoes.usgs.gov/ash/trans/
aviation-threat.html
Q5. To what extent are Federal research programs on aircraft flying
though volcanic ash coordinated, and how easy or difficult is it to
share the research results with relevant stakeholders? What about
coordination with non-U.S. research programs?
A5. Federal agencies including the Federal Aviation Administration
(FAA), NASA, the National Oceanic and Atmospheric Administration, the
National Weather Service, and the National Satellite, Data, and
Information Service are working to improve the state-of-the-art of the
global transport models needed to accurately predict volcanic ash plume
location and dispersion.
Information has been shared through two international forums to
date--one in Seattle, Washington in 1991 and a second in Alexandria,
Virginia in 2004.
The International Civil Aviation Organization (ICAO) continues to
advocate increased scientific understanding of ash cloud dynamics. In
May 2010 ICAO called for establishment of the International Volcanic
Ash Task Force (IVATF) to develop during the next year a global safety
risk management framework that will make it possible to determine the
safe levels of operation in airspace contaminated by volcanic ash. The
IVATF will closely coordinate with ICAO's International Airways
Volcanic Watch Operational Procedures Study Group and ICAO's European
and North Atlantic Volcanic Ash Task Force. Mr. Steve Albersheim of the
FAA has been nominated to represent the United States on the IAVTF and
will coordinate U.S. participation in the task force activities.
Answers to Post-Hearing Questions
Responses by Dr. Jack A. Kaye, Earth Science Division, National
Aeronautics and Space Administration
Questions submitted by Chairwoman Gabrielle Giffords
Q1. I understand that NASA's MODIS instrument that is flying aboard
the Terra satellite has collected data that provided information on the
horizontal as well as the vertical extent of the volcanic ash plume
over Iceland. To what extent will future planned instruments be capable
of maintaining these types of observations?
A1. The Terra platform, launched in 1999, has two instruments that
provide information about atmospheric particulates: the Moderate
Resolution Imaging Spectroradiometer (MODIS) (http://
modis.gsfc.nasa.gov/) and the Multi-Angle Imaging SpectroRadiometer
(MISR) instrument (http://www-misr.ipl.nasa.gov/). The MODIS instrument
on Terra and its twin on the Aqua satellite provide information about
the horizontal and temporal variability of aerosols, but do not provide
information about their vertical location. However, the MISR
instrument, which is unique to Terra, has demonstrated global
stereoscopic measurement of the heights of many volcanic plumes,
including Eyjafjallajokull. MISR makes height estimates by taking
measurements at nine different viewing angles, ranging from 70.5
degrees in front of the spacecraft to 70.5 degrees behind it. The
multi-angle and multispectral capability of MISR also allows additional
information to be acquired such as wind speed in the plumes and
particle properties such as size and shape.
The Visible Infrared Imaging Radiometer Suite (VIIRS) instrument
will continue the MODIS observations of the horizontal extent of
volcanic ash clouds. The Ozone Mapping and Profiling Suite (OMPS) will
continue the Ozone Monitoring Instrument's (OMI) measurements of
volcanic ash and volcanic sulfur dioxide. Both instruments, VIIRS &
OMPS will fly first on NASA's NPOESS Preparatory Project (NPP) mission
in late 2011 and then on subsequent Joint Polar Satellite System (JPSS)
missions.
The next NASA mission that might produce a data set using both
multispectral (like MODIS) and multi-angle (like MISR) approaches is
the Aerosol/Cloud/Ecosystems (ACE) Mission (http://dsm.gsfc.nasa.gov/
ace/index.html), described by the National Research Council in its 2007
Decadal Survey (Earth Science and Applications from Space: National
Imperatives for the Next Decade and Beyond). The ACE mission is one of
the Survey's ``Tier 2'' missions, and no launch date is currently
scheduled. NASA is currently investing in technology through its Earth
Science Technology Office in order to advance the techniques and
instrumentation that will ultimately be part of the ACE mission (see
ACE-related links in http://esto.nasa.gov/
about-esto-documents.html). Infrared observations
from current (e.g. the AIRS instrument on NASA's AQUA satellite) and
future research (e.g. the CRIS instrument aboard NPP) as well as
operational (e.g. the IASI instrument aboard MetOp) instruments also
contribute to our knowledge of volcanic gases and ash.
Q2. How challenging is it to fuse data from weather satellites,
volcano observatories on the ground and science instruments in orbit?
Is it mostly a technical issue or are there organizational
considerations?
A2. The fusion of data from different types of instruments and
platforms for scientific and/or operational uses certainly constitutes
a technical challenge and can constitute an organizational one as well.
Scientifically, the fusion of very different data types is best done
within the context of a data assimilation system. The more different
the data type, the greater the challenge in the assimilation process
simply because they measure different aspects of the environment. These
challenges include addressing differences in data formats, spatial
resolution, measurement uncertainties, and temporal coverage among the
data sources, along with subtle differences in the actual quantities
being measured. Scientists at NASA and other Federal agencies, most
notably the National Oceanic and Atmospheric Administration (NOAA),
have significant capability in data assimilation. At NASA, most data
assimilation expertise resides within the Global Modeling and
Assimilation Office at the Goddard Space Flight Center--see http://
gmao.gsfc.nasa.gov/. Most of NASA's efforts in data assimilation have
emphasized atmospheric (meteorology, i.e., temperature, moisture,
winds, and non-volcanic aerosols) and also oceanic and land surface
data; assimilation of atmospheric aerosols is currently under
development.
While satellite measurements are important for constraining the
aerosol composition of the atmosphere on a global scale, much
information about the timing and intensity of the volcanic emissions
(most notably ash and sulphur dioxide) can be obtained from ground-
based volcanic observatory data. The improved information of a volcanic
event afforded by accurate surface emissions greatly enhances our
ability to utilize the satellite-based measurements. Although volcanic
emissions have been incorporated in retrospective data assimilation of
the climate record, global multi-agency coordination is still necessary
for this information to be utilized in near real time applications. In
order for NASA's observation and model results to be most useful for
operational purposes, continuing and enhanced cooperation between NASA
personnel and the those of the Volcanic Ash Advisory Centers (VAACs),
building on current successes, will be necessary.
Substantial organizational challenges do not exist, in part owing
to long-time investments in comprehensive data systems, format
standards, and multi-agency science centers such as the Joint Center
for Satellite Data Assimilation and Short-term Prediction Research and
Transition Center (SPoRT).
Q3. It has been reported that Europe needs better models to predict
the path of volcanic ash and that this had been done in other parts of
the world. I understand that more accurate models would allow us to be
surgical in what airspace to close down and what to keep open. So how
does one make a model ``better''? Is more empirical data what is needed
to verify the model's accuracy? What is the most effective way to
collect such empirical data?
A3. There are several approaches which can be used to improve forecast
models. The first step is to improve the initial conditions for such
models so that they start off from conditions as close to reality as
possible. For the volcanic ash case, that means knowledge about the
spatial distribution of particulates and gas phase molecules ejected by
the volcano, as well as the underlying meteorology (temperature,
moisture, clouds) in near-real time. For particulates, it is important
to know not only where they occur, but also their properties (size,
chemical composition, radiative properties). The discrimination of ash
from condensate clouds both horizontally, and especially vertically, is
also important. Other improvements in models can come from sustained
use of observations and advances in theory and modeling approaches in
order to improve the representation of atmospheric processes and
quantitative evaluation of models. Frequently, it is through detailed
comparison of observations with models that modelers best understand
the shortcomings of the models and can focus their energies on their
improvement. The availability of such data is particularly important
when there are only a limited number of case studies for comparison,
which is the case when dealing with major volcanic clouds. These data
are obtained from diverse sources: geosynchronous satellite imagers,
multi-spectral techniques, polar-orbiting satellite instruments, and
high-altitude airborne lidar, creating data fusion challenges. Model
improvement can also come from the ability to resolve more fully the
processes represented in them and the spatial scales at which they
operate. Achieving enhanced resolution in these areas is dependent on
the availability of adequate computational resources, without which
approximations that may degrade model quality are required. The
development, improvement, and utilization of forecast models is a
labor-intensive effort that requires sustained effort by a multi-
disciplinary team able to harness the power of observations, theory,
and computation to provide results for real-time use.
Answers to Post-Hearing Questions
Responses by Ms. Victoria Cox, Senior Vice President, Nextgen and
Operations Planning, Air Traffic Organization, Federal Aviation
Administration
Questions submitted by Chairwoman Gabrielle Giffords
Q1. The FAA Administrator was reported to have suggested that Europe
take the lead in establishing a standard for future volcano situations
but offered FAA's technical assistance. What type of technical
assistance was he referring to and why does he believe Europe should be
taking the lead in establishing a standard?
A1. The FAA will provide assistance to the European community in
establishing a standard for situations related to volcanic eruptions.
This assistance involves many different levels of expertise. The FAA
has already established a team of experts who will be supporting the
FAA on the International Civil Aviation Organization (ICAO) Volcanic
Ash Task Force. The FAA will work in a collaborative decision making
process through the ICAO on the establishment of any global standards
for volcanic ash in support of aviation. Specifically, the FAA in
consultation with the NOAA/NWS/NESDIS will examine the current state-of
the-art of global transport models and define the operational
performance requirements for these models for decision support tools
for operators. In addition, the FAA will work collaboratively with the
United States Geological Survey on the development of good scientific
practices for any proposed international standards that support
modeling.
Q2. What was the extent of FAA's consultation with international
aviation regulatory agencies and aircraft manufacturers in developing
the Special Airworthiness Information Bulletin on volcanic ash
operations FAA released on April 22, 2010?
A2. The FAA participated in a series of international volcanic ash
teleconferences that started on April 17, 2010. On April 22, the FAA
issued Special Airworthiness Information Bulletin (SAIB) NE-10-28 after
close consultation with European and Canadian regulatory agencies and
aviation industry. The FAA worked closely with the European Aviation
Safety Agency as each authority shared their draft safety bulletins
with each other. The regulatory agencies and industry reached consensus
prior to final issuance of our respective bulletins. In addition, the
FAA held separate teleconferences with engine manufacturers to assure a
coordinated industry/regulator response. The FAA also requested each of
the manufacturers to issue immediate guidance to the airlines on
inspections after an ash encounter.
Q3. To what extent are Federal research programs on aircraft flying
through volcanic ash coordinated, and how easy or difficult is it to
share the research results with relevant stakeholders? What about
coordination with non-U.S. research programs?
A3. The FAA does not sponsor any specific Federal research program that
addresses aircraft flying through volcanic ash. There is research
supported by other Federal agencies that examines the state-of-the-art
in modeling, forecasting, and using remote sensing to provide greater
accuracy on the location of ash clouds. These combined programs result
in a body of knowledge that supports the issuance of warning messages
to avoid or mitigate ash encounters. Similar to our work in forecasting
convective weather, this research is focused on ash avoidance--not on
engine tolerance. The International Civil Aviation Organization, the
World Meteorological Organization, and the International Union Geodesy
and Geophysics work collaboratively to promote scientific understanding
of volcanic eruptions and subsequent ash clouds that affect aviation.
The information is shared at international fora and through peer review
of published papers. All information garnered from these fora are
shared with all interested stakeholders.
Q4. As you know, the National Weather Service's (NWS) Volcanic Ash
Advisory Centers (VAAC) and Meteorological Watch Offices (MWO) provide
warnings and advisories to the aviation industry regarding volcanic ash
hazards. Such weather products area a vital component of FAA's air
traffic control system.
a. During recent volcanic ash incidents, how would you
characterize the role of the NWS and the working relationship
between FAA and NWS?
A4a. The FAA and NWS work collaboratively in a positive manner on
detecting and reporting volcanic ash that can pose a hazard to
aviation. As you have noted, the NWS provides advisories and warning
messages from VAAC and the MWO respectively. The FAA's responsibility
is to disseminate the information to flight crews and airline operation
centers. The FAA operates and maintains the aeronautical fixed services
(AFS) that disseminate all ICAO-compliant messages to stakeholders.
These messages receive high priority distribution over the AFS and are
immediately integrated into support decision tools for flight planning
purposes.
With regard to the eruption of Mount Eyjafjallajokull, the NWS had
no direct involvement because the ash cloud did not affect a U.S.
Flight Information Region under the responsibility of a NWS VAAC. The
role of the Washington VAAC was to advise users to check the London
VAAC for information on the ash cloud. The FAA also worked
collaboratively with National Air Traffic Services on contingency plans
for the overseas tracks that were available to avoid the ash cloud.
b. How did the NWS work products mitigate the impact these
incidents had on aviation?
A4b. Although the ash cloud that resulted from the eruption of Mount
Eyjafjallajokull did not affect a U.S. Flight Information Region, the
Washington VAAC, if requested by the FAA, would provide any pertinent
information in support of traffic flow management as to how the ash
cloud might affect operations.
Answers to Post-Hearing Questions
Responses by Captain Linda M. Orlady, Executive Air Safety Vice Chair,
Air Line Pilots Association, International
Questions submitted by Chairwoman Gabrielle Giffords
Q1. A Wall Street Journal article reported the following:
Meanwhile, commercial pilot groups remain concerned
about the safety implications of the current situation.
For instance, the Air Line Pilots Association, the
largest pilot union in North America, on Friday warned
members to identify alternate or escape routes to avoid
ash clouds. Descending and turning around is
recommended by the union, rather than climbing through
such clouds. Upon encountering volcanic debris, ALPA
recommends that pilots reduce engine thrust to idle and
don oxygen masks. And the union's update stressed that
if an engine shuts down, it may take longer and be
harder to restart than normal.
Is such a warning from ALPA unusual? What has been the feedback
from your members?
A1. Safety guidance provided by ALPA to its member pilots is not
unusual. When ALPA becomes aware of a safety concern such as a
potential volcanic eruption which could have an immediate impact to a
broad spectrum of our members, the applicable information is then
distributed to our members via ALPA Safety Alerts and/or Operational
Bulletins. For example, since 2005 ALPA has issued 64 Safety Alerts and
Operational Bulletins, four of which have been related to volcanic
activity. In the case of potential volcanic ash encounters, the
guidance provided by ALPA is considered by its members as useful backup
information which is complementary and consistent with guidance from
operators, aircraft manufactures and the FAA. The feedback received
from our membership is that these Safety Alerts and Operational
Bulletins are quite helpful and are often shared with the management of
their airline for further dissemination.
Q2. In your statement, you raised an issue that has been seldom
mentioned by the media following the Icelandic volcano eruption, namely
that volcanic gases such as Sulfur Dioxide (SO2) or Hydrogen
Sulfide (H2S) could pose potential health hazards to
passengers and crews. Who do you believe should be conducting research
in the health effects of volcanic ash on aircraft passengers and crews?
A2. ALPA believes the FAA should take the lead in sponsoring and
conducting research on the effects of volcanic gases on aircraft
occupants, and in particular the FAA Civil Aerospace Medical Institute
(CAMI) located in Oklahoma City. CAMI is the medical certification,
research, education, and occupational health wing of the FAA's Office
of Aerospace Medicine. The goal of CAMI is to enhance aviation safety.
Q3. At the hearing, we discussed the need for onboard warning of
volcanic ash conditions. How high a priority is it for pilots that we
have such an airborne capability?
A3. Currently aircraft weather radar systems cannot detect volcanic ash
clouds. Consequently, at night or in low visibility conditions, pilots
have no way of knowing where the potential danger areas are other than
by weather forecast or reports from other pilots who have encountered
the ash cloud. Forecast information is by its nature an estimation
rather than a direct observation of actual conditions. Even reports
from other pilots do not necessarily reflect what may be occurring
immediately around another aircraft. If in the future, pilots are
expected to consider operations in some scientifically pre-determined
acceptable levels of volcanic ash concentration, then there must be
some onboard sensing and warning capability to enable the pilot to
remain clear of the danger areas. Until such capabilities are available
to the pilots, flight into known volcanic ash areas of any
concentration level is to be avoided.
Questions submitted by Representative Pete Olson
Q1. Your statement emphasized the importance of developing
standardized data products for use by flight crews, dispatchers and air
traffic controllers to track volcanic clouds. Presumably, your peers at
other carriers here and abroad would similarly benefit from a common
set of standards and definitions. What organization, in your view,
should lead this effort, and why hasn't this type of standardized data
format already been implemented?
A1. In our view, the FAA would be the lead organization within the U.S.
for coordinating the development of standardized data products to track
and detect volcanic ash clouds. And to effectively achieve a global
standardization of definitions and products, the International Civil
Aviation Organization (ICAO) would lead with the FAA participating. The
FAA can better answer the status of any such activity and why products,
if available, have not already been implemented.
Q2. Following resumption of air operations in Europe, including
flights into or near airspace containing volcanic ash, what has been
the anecdotal experience of operators and flight crews? Are they seeing
any surprises with respect to engine damage, abrasion, or degradation
of other aircraft systems? Have air service authorities become more
adept at coordinating traffic? Have the volcanic could models proved
reliable?
A2. Since the resumption of air operations in Europe we have seen a
heightened awareness by the aircrews concerning the potential dangers
of volcanic ash encounters. There has also been significant activity
among the European aviation regulators and industry to determine if an
acceptable concentration level of volcanic ash can be established for
safe flight. But until any new policy or technology is provided, we
have advised our membership to stay fully cognizant of and to abide by
their particular airline's policy for flight in the vicinity of
volcanic ash. To the best of our knowledge the U.S. air carriers and
the FAA, although looking into the matter, have not changed their
previous policies that flight into known volcanic ash conditions is to
be avoided. Consequently, we have not seen a rise in the amount of
damage to aircraft due to inadvertent volcanic ash encounters. We are
not aware if there has been any change in the difficulty of
coordination of air traffic with respect to volcanic activity or if the
forecast models have been updated. However, we are concerned that
flight safety would be compromised if new policies are implemented
where pilots are expected to enter into known areas of volcanic ash
concentration, yet are not equipped with the means to measure if the
concentration levels are within pre-determined acceptable thresholds.
Answers to Post-Hearing Questions
Responses by Mr. Roger Dinius, Flight Safety Director, GE Aviation
Questions submitted by Chairwoman Gabrielle Giffords
Q1. It is probably impractical and uneconomical to design a jet engine
that can withstand all volcanic ash conditions. From what we know about
aircraft engines, aviation safety, and the economics of the airline
industry, what is the best that we can expect from future engine
technology improvements?
A1. Today GE & our partners have approximately 25,000 engines operating
world wide in commercial service. It is expected to be economically
impractical for all engines in the fleet to be retrofitted if a
``volcanic ash kit'' were identified.
It is not anticipated that significant technology advances will be
made to ``harden'' modern commercial turbojet engines to volcanic ash
exposure. There is not an anticipated commercial market for an engine
robust to volcanic ash, if it costs any more than today's engines.
Technologies would be required to: 1) eliminate the need for hot
section cooling, 2) an ``ash-phobic'' coating would be required on all
hot section components, and 3) advances would be required in anti-
erosion materials. Additionally, oil system components would need to be
designed to be robust to ash contamination.
Q2. Captain Orlady indicated in her statement that aircraft
certification requirements will need to be updated to provide for more
ruggedized aircraft health monitoring systems and management processes.
Recognizing that GE aircraft engines are part of the aircraft's overall
system, what are your views on Captain Orlady's suggestion?
A2. If the industry elects intentionally fly into volcanic ash, a
``history record'' will likely be required to keep track of the
volcanic ash exposure. This ``history record'' will likely involve a
volcanic ash exposure record that will likely be a function of power
setting of engine, engine operability margin available, local ash
concentration and exposure time. Today, technology does not support a
sensor that can determine the local ash concentration on-board
commercial aircraft. This is not expected to be operationally
economical, and it will likely degrade overall aviation safety. GE does
not recommend flight into visible volcanic ash.
Q3. I understand that engine manufacturers and international aviation
regulators had been in discussion for a few years on trying to
establish the concentration level of volcanic ash an engine could
tolerate without causing a safety hazard. Six days after the closure of
European airspace, consensus was reached. Why was consensus so
difficult to achieve and what finally precipitated an agreement?
A3. GE was not involved in establishing an engine tolerance level for
volcanic ash over the past few years, until April 16, 2010. The
difficulty in establishing a tolerable level of volcanic ash centers on
the assumption that a concentration level is all that is important to
understand engine damage. Actually it is only one of several factors
critical to assess the impact. It is anticipated to understand engine
tolerance requires knowledge of exposure time, engine condition prior
to encounter, particle size distribution, and ash chemistry. The
airspace closure over Europe brought engine manufacturers and
government agencies together to assess available data to establish the
current interim ash concentration limits. Long-term engine impacts of
operations in these levels of volcanic are unknown. GE continues to
recommend against flight in visual volcanic ash.
Questions submitted by Representative Pete Olson
Q1. Your written statement noted that it is `acceptable' for jets to
fly through volcanic clouds having ash equal to or less than 2
milligrams per cubic meter. What do you mean by using the term
`acceptable'? Are modem turbojet engines capable of operating in such
an environment without enduring any lasting, long-term damage? Would
operators be at risk of having to overhaul their engines on a shorter
cycle because of this level of exposure?
A1. ``Acceptable'' here referred to a qualitative engine impact
assessment where engines impacts are limited to economic impacts and
not operational safety impacts. If engines are operated in volcanic ash
environments, up to 2 milligrams per cubic meter, cumulative engine
damage is anticipated which will drive engines off wing early and
require a shop level overhaul to restore engine performance. GE does
not recommend flight into visible volcanic ash.
Q2. Following resumption of air operations in Europe, including
flights into or near airspace containing volcanic ash, what has been
the anecdotal experience of operators and flight crews? Are they seeing
any surprises with respect to engine damage, abrasion, or degradation
of other aircraft systems? Have air service authorities become more
adept at coordinating traffic?
A2. No unserviceable conditions have been observed to date from
volcanic ash exposure following the April 2010 Icelandic volcanic
activity, to my knowledge. No flight crew reports of volcanic ash
encounters impacting engine operation have been reported, to my
knowledge. Based on inspection results to date engines accumulated ash,
but not to a point of being unserviceable. I don't have an expertise in
air traffic or the air service authorities capabilities, so can't
comment on their past or current capabilities.