[Federal Register Volume 64, Number 130 (Thursday, July 8, 1999)]
[Proposed Rules]
[Pages 37018-37024]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-17360]



[[Page 37017]]

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Part V





Department of Transportation





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Federal Aviation Administration



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14 CFR Part 91



Reduced Vertical Separation Minimum;



Proposed Rule

  Federal Register / Vol. 64, No. 130 / Thursday, July 8, 1999 / 
Proposed Rules  

[[Page 37018]]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 91

[Docket No. FAA-1999-5925; Notice No. 99-10]
RIN 2120-AG82


Reduced Vertical Separation Minimum

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: The Federal Aviation Administration (FAA) intends by this 
proposed rule to enable the implementation of Reduced Vertical 
Separation Minimum (RVSM) in Pacific oceanic airspace. RVSM is the 
reduction of the vertical separation of aircraft from 2,000 feet to 
1,000 feet at flight levels (FLs) between FL 290 (29,000 feet) and FL 
410 (41,000 feet). RVSM is applied only between aircraft that meet 
stringent altimeter and auto-pilot performance requirements. RVSM is 
currently applied only in North Atlantic (NAT) Minimum Navigation 
Performance Specification (MNPS) airspace. The introduction of RVSM in 
Pacific oceanic airspace would make more fuel and time efficient flight 
levels and tracks available to operators and would enhance airspace 
capacity. Since March 1997 in the North Atlantic, RVSM has been shown 
to maintain an acceptable level of safety. International RVSM planning 
groups have agreed to implement RVSM on or before February 24, 2000.

DATES: Comments must be submitted on or before September 7, 1999.

ADDRESSES: Comments on this NPRM should be delivered or mailed, in 
triplicate, to: U.S. Department of Transportation Dockets, Docket No. 
[FAA-1999-5925], 400 Seventh Street SW., Room Plaza 401, Washington, DC 
20590. Comments must indicate the Docket Number. Comments also may be 
submitted electronically to the following Internet address: 9-NPRM-
[email protected]. Comments may be examined in Room Plaza 401 weekdays 
between 10:00 a.m. and 5:00 p.m. weekdays, except Federal holidays.

FOR FURTHER INFORMATION CONTACT: Mr. Roy Grimes, AFS-400, Flight 
Technologies and Procedures Division, Flight Standards Service, Federal 
Aviation Administration, 600 Independence Avenue, SW., Washigton, DC 
20591, telephone (202) 267-3734.

SUPPLEMENTARY INFORMATION:

Comments Invited

    This action is a product of international agreements under which 
the international aviation community, including the United States, 
plans to implement RVSM in Pacific airspace. The International Civil 
Aviation Organization (ICAO) Asia/Pacific Air Navigation Planning and 
Implementation Regional Group (APANPIRG), the Informal Pacific Air 
Traffic Service Coordinating Group (IPACG), and the Informal South 
Pacific Air Traffic Service Coordinating Group have concluded that 
Pacific oceanic traffic will continue to increase significantly in the 
next few years. To accommodate this increase in air traffic, these 
groups have established a goal of implementing RVSM in Pacific Oceanic 
airspace on or before February 24, 2000. Affected FIRs include 
Anchorage Arctic, Anchorage Continental, Anchorage Oceanic, Auckland 
Oceanic, Brisbane, Edmonton, Honiara, Los Angeles, Melbourne, Nadi, 
Naha, Nauru, New Zealand, Oakland, Oakland Oceanic, Port Moresby, 
Seattle, Tahiti, Tokyo, and Vancouver.
    Interested persons are invited to participate in this proposed 
rulemaking by submitting such written data, views, or arguments, as 
they may desire. Comments relating to the environmental, energy, 
federalism, or economic impact that may result from adopting the 
proposals in this notice are also invited. Comments that provide the 
factual basis supporting the views and suggestions presented are 
particularly helpful in developing reasoned regulatory decisions. 
Comments should identify the regulatory docket number and be submitted 
in triplicate to the above-specified address.
    Because this proposed rule was developed as a result of an 
international agreement, comments deemed substantive will be presented 
for consideration and reviewed by the international community under the 
auspices of ICAO. If considered salient, the comments will be included 
for use by all participating member States.
    All comments received will be available both before and after the 
closing date for comments in the Department of Transportation Docket 
for examination by interested persons.
    The FAA will acknowledge receipt of a comment if the commenter 
includes a self-addressed, stamped postcard on which the following 
statement is made: ``Comments to Docket No. FAA-1999-5925.'' The FAA 
will date, time stamp, and return the postcard.

Availability of This Document

    Any person may obtain a copy of this document by submitting a 
request to the Federal Aviation Administration, Office of Rulemaking, 
ARM-1, 800 Independence Avenue, SW., Washington, DC 20591, or by 
calling (202) 267-9677. Communications must identify the docket number 
of this rule.
    Persons interested in being placed on the mailing list for future 
rulemaking actions should request from the above office a copy of 
Advisory Circular No. 11-2A, Notice of Proposed Rulemaking Distribution 
System, that describes the application procedure.
    An electronic copy of this document may be downloaded, using a 
modem and suitable communications software, from the FAA regulations 
section of the Fedworld electronic bulletin board service (telephone 
703-321-3339), the Federal Register's electronic bulletin board service 
(telephone: 202-512-1661), or the FAA's Aviation Rulemaking Advisory 
Committee Bulletin Board Service (800-322-2722 or 202-267-5948).
    Internet users may reach the FAA's web page at http://www.faa.gov 
or the Federal Register's Web page at http://www.access.gpo.gov/
su__docs for access to recently published rulemaking documents.

Background

Statement of the Problem

    Air traffic on Pacific routes between the U.S. and Asia has 
increased steadily in the past few years and is projected to continue 
to increase. The North Pacific Track System (NOPAC) is the densest 
oceanic traffic area in the Pacific. Between 1994 and 198, the annual 
traffic count on the NOPAC increased from 42,305 to 60,772 flights 
which represents an increase of 44 percent. The FAA Aviation Forecast 
for Fiscal Years 1998-2010 estimates that transpacific passenger 
traffic will continue to increase at 6.6 percent per year through 2010. 
Studies conducted by independent aviation industry analysts forecast 
the Pacific area to be the fastest growing area for flights to/from the 
United States.
    Unless action is taken, as traffic increases, the opportunity for 
aircraft to fly at fuel-efficient altitudes and tracks will be 
significantly diminished. In addition, air traffic service providers 
may not be able to accommodate greater numbers of aircraft in the 
airspace without invoking restrictions that can result in traffic 
delays and fuel penalties.
    With air traffic levels increasing annually worldwide, FAA airspace

[[Page 37019]]

planners and their international counterparts continually explore 
methods of enhancing the air traffic control (ATC) system's ability to 
accommodate traffic in a safe and efficient manner. NAT airspace was 
chosen to be the first airspace for RVSM introduction because it is the 
busiest oceanic airspace in the world and traffic is forecast to 
continue to increase. The NAT Traffic Forecasting Group Report shows 
that the number of annual flight operations increased 30 percent 
between 1991 and 1996 with a forecast 67 percent rise over the 1992 
level of 228,200 by 2002.
    Prior to the introduction of RVSM, 27 percent of flights in NAT 
airspace were issued clearances on tracks and at altitudes other than 
those requested by the operators in their filed flight plans. These 
flights were, therefore, generally conducted at less than optimum 
tracks and altitudes for the aircraft, resulting in time and fuel 
inefficiencies.
    The North Atlantic Implementation Management Group has observed the 
following improvements in NAT operations due to the introduction of 
RVSM:
    1. 50 percent of the fuel penalty attributed to NAT system 
operation was eliminated. (The total NAT system fuel penalty is 
estimated based on track design, meteorological forecast, cruise level 
and traffic congestion penalties).
    2. 25 percent fewer fixed tracks were required to be published. 
(This allows more airspace for operators to fly preferred tracks).
    3. There was a 5 percent increase in flights cleared to fly both at 
the altitude and on the track that the operator requested.
    RVSM alleviates the limitation on air traffic management at high 
altitudes imposed by the conventional 2,000-foot vertical separation 
standard. Below FL 290, air traffic controllers can assign aircraft 
operating under Instrument Flight Rules (IFR) altitudes a minimum of 
1,000 feet apart. Above FL 290, however, the Conventional Vertical 
Separation Minimum (CVSM) is 2,000 feet.

    Note: Flight levels are stated in digits that represent hundreds 
of feet. The term flight level is used to described a surface of 
constant atmospheric pressure related to a reference datum of 29.92 
inches of mercury. Rather than adjusting altimeters for changes in 
atmospheric pressure, pilots base altitude readings above the 
transition altitude [in the United States, 18,000 feet] on this 
standard reference. FL 290 represents the pressure surface 
equivalent of 29,000 feet based on the 29.29'' Hg datum; FL 310 
represents 31,000 feet, and so on.)

    The 2,000-foot minimum vertical separation restricts the number of 
flight levels available. Flight levels 310, 330, 350, 370, and 390 are 
flight levels at which aircraft crossing oceanic airspace operate most 
economically. At peak hours these FLS can become congested. When all 
RVSM FLs are utilized, six additional flight levels are available: FLs 
300, 320, 340, 360, 380, and 400. Increasing the number the FLs 
available in the Pacific region is projected to achieve operator 
benefits similar to those achieved in the NAT (i.e., mitigation of fuel 
penalties attributed to the inability to fly optimum altitudes and 
tracks). In the Pacific, RVSM is initially planned to be implemented 
between FL 290 and FL 390 (inclusive). At this time, traffic density 
above FL 390 does not warrant implementing RVSM at FL 400 and FL 410.
    Another factor that has led Pacific planners to believe that RVSM 
implementation should be pursued aggressively is that a large 
percentage of Pacific operators and aircraft have already received 
approval to conduct RVSM operations. This is due to the fact that 
Pacific operators conduct operations worldwide and therefore, have been 
required to obtain RVSM approval to operate in NAT RVSM airspace. 
Aircraft that have been approved for RVSM are approved for RVSM in any 
area of the world where it is applied. The Pacific RVSM Implementation 
Task Force (Task Force) has reviewed the RVSM approval status of 
Pacific operators and aircraft and found that approximately 36 percent 
of Pacific operations are already conducted by RVSM approved operators 
and projected that this figure will grow to 56 percent in the near 
term.

History

    The ICAO APAN/PIRG develops and provides oversight for plans and 
policy related to air navigation in the Pacific and Asia. The APAN/PIRG 
established the Task Force to develop and implement RVSM policy and 
programs in the Pacific. The Task Force is using the policy and 
criteria developed in other ICAO forums to build the RVSM program for 
the Pacific. The following reviews the RVSM program development in U.S. 
and ICAO forums.
    Rising traffic volume and fuel costs, which made flight at fuel-
efficient altitudes a priority for operators, sparked an interest in 
the early 1970s in implementing RVSM above FL 290. In April 1973, the 
Air Transport Association of America (ATA) petitioned the FAA for a 
rule change to reduce the vertical separation minimum to 1,000 feet for 
aircraft operating above FL 290. The petition was denied in 1977 in 
part because (1) Aircraft altimeters has not been improved 
sufficiently, (2) improved maintenance and operational standards has 
not been developed, and (3) altitude correction was not available in 
all aircraft. In addition, the cost of modifying nonconforming aircraft 
was prohibitive. The FAA concluded that granting the ATA petition at 
that time would have adversely affected safety. Nevertheless, the FAA 
recognized the potential benefits of RVSM under certain circumstances 
and continued to review technological developments, committing 
extensive resources to studying aircraft altitude-keeping performance 
and necessary criteria for safely reducing vertical separation above FL 
290. These benefits and data showing that implementing RVSM is 
technically feasible have been demonstrated in studies conducted 
cooperatively in international forums, as well as separately by the 
FAA.
    Because of the high standard of performance and equipment required 
for RVSM, the FAA advocated initial introduction of RVSM in oceanic 
airspace where special navigation performance standards were already 
required. Special navigation areas require high levels of long-range 
navigation precision due to the separation standard applied. RVSM 
implementation in such airspace requires an increased level of 
precision demanded of operators, aircraft, and vertical navigation 
systems.
    On March 27, 1997, RVSM was implemented in one such special 
navigation area of operation, the NAT MNPS, established in the ICAO NAT 
Region. In designated NAT MNPS airspace, tracks are spaced 60 nautical 
miles (NM) apart. Between Fs 310 and 390 (inclusive), aircraft are 
separated vertically by 1000 feet. All aircraft operating in this 
airspace must be appropriately equipped and capable of meeting required 
lateral navigation performance standards of part 91, section 91.705 and 
vertical navigation performance standards of part 91, section 91.706. 
Operators must follow procedures that ensure the standards are met, and 
flight crews are trained and qualified to meet the standards. Each 
operator, aircraft, and navigation system combination must receive and 
maintain authorization to operate in the NAT MNPS. The NATSPG Central 
Monitoring Agency monitors NAT MNPS. The NATSPG Central Monitoring 
Agency monitors NAT aircraft fleet performance to ensure that a safe 
operating environment is maintained.
    FAA data indicate that the altitude-keeping performance of most 
aircraft flying in oceanic airspace can meet the

[[Page 37020]]

standards for RVSM operations. The FAA and ICAO research to determine 
the feasibility of implementing RVSM included the following four 
efforts:
    1. FAA Vertical Studies Program. This program began in mid-1981, 
with the objectives of collecting and analyzing data on aircraft 
performance in maintaining assigned altitude, developing program 
requirements to reduce vertical separation, and providing technical and 
operational representation on the various working groups studying the 
issue outside the FAA.
    2. RTCA Special Committee (SC)-150. RTCA, Inc., (formerly Radio 
Technical Commission for Aeronautics) is an industry organization in 
Washington, DC, that addresses aviation technical requirements and 
concepts and produces recommended standards. When the FAA hosted a 
public meeting in early 1982 on vertical separation, it was recommended 
that RTCA be the forum for development of minimum system performance 
standards for RVSM. RTCA SC-150 was formed in March 1982 to develop 
minimum system performance requirements, identify required improvements 
to aircraft equipment and changes to operational procedures, and assess 
the impact of the requirements on the aviation community. SC-150 served 
as the focal point for the study and development of RVSM criteria and 
programs in the United States from 1982 to 1987, including analysis of 
the results of the FAA Vertical Studies Program.
    3. ICAO Review of the General Concept of Separation Panel (RGCSP). 
In 1987, the FAA concentrated its resources for the development of RVSM 
programs in the ICAO RGCSP. The U.S. delegation to the ICAO RGCSP used 
the material developed by SC-150 as the foundation for U.S. positions 
and plans on RVSM criteria and programs. The Panel's major conclusions 
were:
     RVSM is technically feasible without imposing unreasonably 
demanding technical requirements on the equipment.
     RVSM provides significant benefits in terms of economy and 
en route airspace capacity.
     Implementation of RVSM on either a regional or global 
basis requires sound operational judgment supported by an assessment of 
system performance based on: aircraft altitude-keeping capability, 
operational considerations, systems performance monitoring, and risk 
assessment.
    4. NATSPG and the NATSPG Vertical Separation Implementation Group 
(VISG).
    The NATSPG Task Force was established in 1988 to identify the 
requirements to be met by the future NAT Region Air traffic services 
systems; to design the framework for the NAT airspace system concept; 
and to prepare a general plan for the phased introduction of the 
elements of the concept. The objective of this effort was to permit 
significant increases in airspace capacity and improvement in flight 
economy. At the meeting of the NATSPG in June 1991, all of the NAT air 
traffic service provider States, as well as the International Air 
Transport Association (IATA) and International Federation of Airline 
Pilots Association (IFALPA), endorsed the Future NAT Air Traffic 
Services System Concept Description developed by the NATSPG Task Force. 
With regard to the implementation of RVSM, the Concept Description 
concludes that priority must be given to implementation of this measure 
as it is believed to be achievable within the early part of the concept 
time frame. The NATSPG's initial goal was to implement RVSM between 
1996 and 1997. To meet this goal, the NATSPG established the VSIG in 
June 1991 to take the necessary actions to implement RVSM in the NAT. 
These actions included:
     Programs and documents to approve aircraft and operators 
for conducting flight in the RVSM environment and to address all issues 
related to aircraft airworthiness, maintenance, and operations. The 
group has produced guidance material for aircraft and operator approval 
that ICAO has distributed to civil aviation authorities and NAT users. 
Also, ICAO has planned that the guidance material be incorporated in 
the approval process established by the States.
     Developing the system for monitoring aircraft altitude-
keeping performance. This system is used to observe aircraft 
performance in the vertical plane to determine that the approval 
process is uniformly effective and that the RVSM airspace system is 
safe.
     Evaluating and developing ATC procedures for RVSM, 
conducting simulation studies to assess the effect or RVSM on ATC, and 
developing documents to address ATC issues.
    The ICAO Limited NAT Regional Air Navigation Meeting held in 
Portugal in November 1992 endorsed the NATSPG RVSM implementation 
program. At the meeting, it was concluded that RVSM implementation 
should be pursued. The FAA concurred with the conclusions of the NATSPG 
on RVSM implementation.

Reference Material

    The FAA and other entities studying the issues of RVSM requirements 
have produced a number of studies and reports. The FAA used the 
following documents in the development of this amendment:
     Summary Report of United States Studies on 1,000-Foot 
Vertical Separation Above Flight Level 290 (FAA, July 1988).
     Initial Report on Minimum System Performance Standards for 
1,000-Foot Vertical Separation Above Flight Level 290 (RTCA SC-150, 
November 1984); the report provides information on the methodology for 
evaluating safety, factors influencing vertical separation, and 
strawman system performance standards.
     Minimum System Performance Standards for 1,000-Foot 
Vertical Separation Above Flight Level 290 (Draft 7, RTCA, August 
1990); the FAA concurred with the material developed by RTCA SC-150.
     The Report of RGCSP/6 (ICAO, Montreal, 28 November-15 
December 1988) published in two volumes. Volume 1 summarizes the major 
conclusions reached by the panel and the individual States. Volume 2 
persents the complete RVSM study reports of the individual State:
     European Studies of Vertical Separation Above FL 290--
Summary Report (prepared by the EUROCONTROL Vertical Studies Subgroup).
     Summary Report of United States Studies on 1,000-Foot 
Vertical Separation Above Flight Level 290 (prepared by the FAA 
Technical Center and ARINC Research Corporation).
     The Japanese Study on Vertical Separation.
     The Report of the Canadian Mode C Data Collection.
     The Results of Studies on the Reduction of Vertical 
Separation Intervals for USSR Aircraft at Altitudes Above 8,100 m 
(prepared by the USSR).
     Report of RGCSP/7 (Montreal, 30 October-20 November 1990) 
containing a draft Manual on Implementation of a 300 M (1,000 Ft) 
Vertical Separation Minimum (VSM) Between FL 290 and 410 Inclusive, 
approved by the ICAO Air Navigation Commission in February 1991 and 
published as ICAO Document 9574.
     Interim Guidance Material 91-RVSM, ``Approval of Aircraft 
and Operators for Flight in Airspace Above FL 290 Where a 1,000 Foot 
Vertical Separation is Applied'' (March 14, 1999). The interim guidance 
continues to provide recommended procedural steps for obtaining FAA 
approval.

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     AC No. 91-70, ``Oceanic Operations'' (September 6, 1994).
     Flight Standards Handbook Bulletin for Air Transportation 
(HBAT) ``Approval of Aircraft and Operators for Flight in Airspace 
Above Flight Level 290 Where a 1,000 Foot Vertical Separation Minimum 
is Applied'' (HBAT 97-02).
     NATSPG Airspace Monitoring Sub-group Vertical Monitoring 
Report. (Issued quarterly)

Related Activity

    Projected increases in pacific oceanic air traffic and the 
successful implementation of RVSM operations in the NAT support the 
addition of RVSM in the Pacific. Pacific operators and Air Traffic 
Service (ATS) providers have requested that RVSM be pursued 
aggressively.
    The Pacific RVSM Implementation Task Force is the international 
body that is developing Pacific RVSM implementation plans. The Task 
Force is chaired by an FAA representative from the Air Traffic 
International Staff and supported by an ICAO representative from the 
Asia/Pacific Regional Office. The Task Force has three standing sub-
groups: the Air Traffic Operations Group, the Aircraft Operations and 
Airworthiness Group and the Safety and Monitoring Group. The working 
groups are chaired by FAA air traffic and flight standards specialists. 
The Task Force includes representatives from Asia and Pacific civil 
aviation authorities, operators and the pilot and air traffic 
controller associations. The Task Force meets at approximately 
quarterly intervals to develop policy and procedure documents and to 
progress implementation tasks.
    The Task Force chairperson and the three sub-group chairpersons 
will oversee the two phases of the Pacific implementation process:

System Verification Phase

    During the verification phase, aircraft will continue to be 
separated vertically by 2,000 feet. Operators and aircraft that have 
not already been approved for RVSM will begin to receive RVSM approval 
in accordance with part 91, section 91.706 and Appendix G (or their 
equivalent for foreign operators). The overall objectives of the system 
verification phase are to:
    1. Confirm that the target level of safety (TLS) will continue to 
be met.
    2. Confirm that aircraft approved for RVSM operation demonstrate 
altitude-keeping performance that meets RVSM standards. This will be 
achieved by:
     Identifying and eliminating any causes of out-of-tolerance 
altitude-keeping performance, in general or for specific aircraft 
groups; and
     Monitoring a sample of RVMS-approved aircraft and 
operators that is representative of the total Pacific population.
    3. Verify that operational procedures adopted for RVSM are 
effective and appropriate.
    4. Confirm that the altitude-monitoring program is effective. The 
principal purpose of this phase has been to gain confidence that the 
operational trial phase can begin.

Initial Operational Capability/System Monitoring Phase

    When the objectives of the system verification phase have been met, 
RVSM will be implemented at designated flight levels. The first year 
after implementation is considered the operational trials phase. The 
objectives of the operational trial phase are to:
    1. Continue to collect altitude-keeping performance data.
    2. Increase the level of confidence that safety goals are being 
met.
    3. Demonstrate operationally that there are no difficulties with 
RVSM implementation.
    Beginning February 24, 2000, only RVSM compliant aircraft will be 
cleared to operate in the major Pacific FIRs between FLs 290 and 390 
(inclusive). Aircraft that are not RVSM compliant (e.g., State 
aircraft, ferry and maintenance flights) will only be cleared to 
operate between FLs 290 and 390 (inclusive), traffic permitting, after 
prior coordination with the appropriate oceanic center. 2,000-foot 
vertical separation will be applied to such aircraft.
    Provided that all requirements continue to be met, at the end of 
one year, RVSM will be declared fully operational.

Altitude-Keeping Performance

    For the past three years, the FAA, in conjunction with the NATSPG, 
has monitored aircraft altitude-keeping performance of RVSM approved 
aircraft. A major objective of monitoring is to establish that the 
altitude-keeping performance of the aircraft fleet operating in 
airspace where RVSM is applied continues to meet minimum requirements.
    Altimeter system error (ASE) is the major component of aircraft 
altitude-keeping performance. In the past three years, 36,000 
measurements of altimetry system error have been taken for over 3,000 
different airframes. Those measurements have shown that the altitude-
keeping performance of aircraft approved for RVSM operations is 
significantly better than the minimum requirement. The ASE requirement 
established for RVSM is that average ASE not exceed 80 feet and 99.9% 
of ASE observed not exceed 245 feet. The monitoring results have shown 
that actual average ASE is -4 feet and 99.9% of ASE is within 156 feet.
    The FAA has determined that the appropriate method of assessing 
collision risk is the Reich collision risk model (CRM). As noted in AC 
No. 91-70, Oceanic Operations, collision risk refers to the number of 
midair accidents likely to occur due to the loss of separation in a 
prescribed volume of airspace for a specific number of flight hours.
    Collision Risk Methodology (CRM) was used to develop the 
requirements for safe implementation of a 1,000-foot vertical 
separation standard. The United States supported the methodology used 
to derive the accepted level of safety for RVSM implementation.
    The TLS that is being used in the North Atlantic and the Pacific 
regions to assess safety is no more than five fatal accidents in 1 
billion flying hours. The level of safety was developed using 
historical data on safety from global sources. One precedent used was a 
period of 100 to 150 years between midair collisions. When the TLS of 5 
accidents in a billion flying hours is projected in terms of a calendar 
year interval between accidents in the Pacific, it yields a theoretical 
interval of approximately 322 years between midair collisions. The 
accepted level of safety is consistent with the acceptable level for 
aircraft hull loss and is based on the precedence of extremely 
improbable events as they relate to system safety, the basis for 
certain requirements in certification regulations such as 14 CFR 
25.1309.
    To ensure that the TLS is met, the FAA is monitoring the total 
vertical error (TVE) and the remaining CRM parameters that are critical 
for safety assessment (probability of lateral and longitudinal 
overlap). TVE is defined as the geometric difference between the 
aircraft and the flight level altitude. To monitor TVE, the FAA has 
deployed measurement systems that will produce estimates of aircraft 
and flight level geometric altitude. The overall goal of monitoring is 
to ensure that airworthiness, maintenance, and operational approval 
requirements result in required system performance (and level of 
safety) in the flight environment on a continuing basis. One such 
measurement/monitoring system is a Global Positioning System (GPS)-

[[Page 37022]]

based monitoring system (GMS). The GMS has been used extensively in the 
NAT along with ground based Height Monitoring Units (HMUs). Due to the 
lack of land masses in the PAC, the GMS will be used for RVSM system 
verification and monitoring.
    The on-going assessment of risk in the North Atlantic over the past 
two years has shown that the TLS of 5 accidents in 1 billion flight 
hours can be met. All sources of error related to aircraft performance 
and to human error have been assessed. One major incident that was 
observed in the on-going monitoring was judged to be a pilot error not 
related to the introduction of RVSM. In this incident, an aircraft did 
not fly the flight level to which it was cleared, but reported to ATC 
that it was flying the cleared level. This incident was advertised to 
the user community for emphasis in pilot training programs.

Current Requirements

    Part 91 Section 91.706 (Operations within airspace designated as 
Reduced Vertical Separation Minimum Airspace.) and Appendix G to Part 
91 (OPERATIONS IN REDUCED VERTICAL SEPARATION MINIMUM (RVSM) AIRSPACE) 
were published in April 1997. They are based on the ICAO Manual on 
RVSM. Technical and operational experts from the FAA, the European 
Joint Airworthiness Authorities (JAA), the aircraft manufacturers, and 
pilot associations developed the criteria in a joint FAA/JAA working 
group. Section 91.706 requires that aircraft and operators meet the 
requirements of Appendix G and receive authorization from the 
Administer prior to flying in airspace where RVSM is applied. Appendix 
G contains requirements in eight sections:

1. Definitions
2. Aircraft Approval
3. Operator Authorization
4. RVSM operations (flight planning into RVSM airspace)
5. Deviation Authority Approval
6. Reporting Altitude-keeping Errors
7. Removal or Amendment of Authority
8. Airspace Designation

    Flight Standards Handbook Bulletin (HBAT) 97-02 entitled ``Approval 
of Aircraft and Operators for Flight in Airspace Above Flight Level 290 
Where 1,000 Foot Vertical Separation Minimum Is Applied'', has been 
distributed through Flight Standards District Offices (FSDOs). This 
document provides guidance to FAA Flight Standards inspectors on the 
process and procedures to follow before approving an operator and its 
aircraft for RVSM operations. It details inspector responsibilities for 
assessment of airworthiness approval, maintenance program approval, and 
operations approval requirements in the rule. It discusses timing, 
process, and maintenance and operations material that the operator 
should submit for FAA review and evaluation normally at least 60 days 
before the planned operation in RVSM airspace. Operators under Title 
14, Code of Federal Regulations (14 CFR) part 91 receive FAA approval 
in the form of a Letter of Authorization (LOA), and operators under 14 
CFR parts 121, 125, and 135 receive Operations Specifications (OPS-
SPEC) approval.
    For operations over the high seas outside the United States, 14 CFR 
91.703 requires that aircraft of U.S. registry comply with Annex 2 
(Rules of the Air) to the Convention on International Civil Aviation. 
Annex 2, amendment 32, effective February 19, 1996, reflects the change 
from 2,000 feet to 1,000 feet vertical separation for Instrument Flight 
Rules (IFR) traffic between FL 290 and FL 410, based on appropriate 
airspace designation, international agreements, and conformance with 
specified conditions.

General Discussion of the Proposal

    The proposal allows operation of civil aircraft of U.S. 
registration in Pacific oceanic airspace where RVSM is applied. It is 
based on improvements in altitude-keeping technology. These 
improvements include:
     Introduction of the air data computer (ADC), which 
provides an automatic means of correcting the known static source error 
of aircraft to improve aircraft altitude measurement capability.
     Development of altimeters with enhanced transducers or 
double aneroid for computing altitude.
    Under this proposal, airspace or routes in the Pacific where RVSM 
is applied would be considered special qualification airspace. Both the 
operator and the specific types of aircraft that the operator intends 
to use in RVSM airspace would have to be approved by the appropriate 
FAA office before the operator conducts flights in RVSM airspace.
    Implementation of a 1,000-foot vertical separation standard above 
FL 290 offers substantial operational benefits to operators, including:
     Greater availability of the most fuel-efficient altitudes. 
In the RVSM environment, aircraft are able to fly closer to their 
optimum altitude at initial level off and through step climbing to the 
optimum altitude during the enroute phase.
     Greater availability of the most time and fuel-efficient 
tracks and routes (and an increased probability of obtaining these 
tracks and routes). Operators often are not cleared on the track or 
route that was filed due to demand for the optimum routes and resultant 
traffic congestion on those routes. RVSM allows ATC to accommodate a 
greater number of aircraft on a given track or route. More time and 
fuel-efficient tracks or routes would therefore be available to more 
aircraft.
     Increased controller flexibility. RVSM gives ATC greater 
flexibility to manage traffic by increasing the number of flight levels 
on each track or route.
     Reduction of pilot and controller work load. When 
controllers are required to re-route aircraft from their filed track 
and/or altitude they are required to re-coordinate and revise 
clearances. Pilots are required to re-program aircraft navigation 
systems (which has been a major cause of navigational errors). RSVM 
will reduce the number of re-routes required and therefore reduce both 
pilot and controller workload.
     Enhanced flexibility to allow aircraft to fly across route 
systems. Operators are often required to remain at lower, less fuel-
efficient altitudes until the aircraft crosses a route system. RVSM 
makes more flight levels available at higher, more fuel-efficient 
altitudes to allow aircraft to cross route systems.
     Enhanced safety in the lateral dimension. Studies indicate 
that RVSM produces a wider distribution of aircraft among different 
tracks and altitudes, resulting in less exposure to aircraft at 
adjacent separation standards. RVSM reduces the number of occasions 
when two aircraft pass each other separated by a single separation 
standard (e.g., 60 nm laterally). The benefit to safety is that, should 
an aircraft enter, as a result of gross navigation error, onto an 
adjacent track, and another aircraft is on that track, there is an 
increased probability that the two aircraft would be flying at 
different flight levels.
    This amendment to Sec. 91.706, Appendix G, Section 8 would add the 
Pacific oceanic FIRs to the list of FIR's where RVSM can be applied

Regulatory Evaluation Summary

    Executive Order 12866 directs federal agencies to promulgate new 
regulations or modify existing regulations after consideration of the 
expected benefits to society and the expected costs. Each federal 
agency shall assess both the costs and the benefits of proposed 
regulations while recognizing that some costs and benefits are 
difficult to

[[Page 37023]]

quantify. A proposed rule is promulgated only upon a reasoned 
determination that the benefits of the proposed rule justify its costs.
    The order also requires federal agencies to assess whether a 
proposed rule is considered a ``significant regulatory action.'' The 
Regulatory Flexibility Act of 1980 requires agencies to analyze the 
economic impact of regulatory changes on small entities. The Office of 
Management and Budget directs agencies to assess the effect of 
regulatory changes on international trade. Finally, Public Law 104-4 
requires federal agencies to assess the impact of any federal mandates 
on state, local, tribal governments, and the private sector.
    In conducting these analyses, the FAA has determined that this 
rule: (1) generates benefits that justify its costs and is not ``a 
significant regulatory action'' as defined in the Executive Order; (2) 
is significant as defined in Department of Transportation's Regulatory 
Policies and Procedures; (3) does not have a significant impact on a 
substantial number of small entities; and (4) does not constitute a 
barrier to international trade. These analyses, available in the 
docket, are summarized below.
    This proposal amends FAR 91, Section 91.706, Section 8 (Airspace 
Designation) by adding the appropriate Pacific Oceanic Flight 
Information Regions (FIRs) where RVSM would be implemented. The 
benefits of this proposed rulemaking are (1) an increase in the number 
of available flight levels, (2) enhance airspace capacity, (3) permit 
operators to operate more fuel/time efficient tracks and altitudes, and 
(4) enhance air traffic controller flexibility by increasing the number 
of available flight levels, while maintaining an equivalent level of 
safety.
    The FAA estimates that this proposed rule would cost U.S. operators 
$21.7 million for the ten-year period 2000-2009 or $19.5 million, 
discounted. Estimated benefits, based on fuel savings for the 
commercial airplane fleet over the years 2000-2009, would be $120 
million, or $83.8 million, discounted. Therefore, based on a 
quantitative and qualitative evaluation of this action, the proposed 
rule would be cost-beneficial.

Initial Regulatory Flexibility Determination

    The Regulatory Flexibility Act of 1980 establishes ``as a principle 
of regulatory issuance that agencies shall endeavor, consistent with 
the objective of the rule and of applicable statutes, to fit regulatory 
and informational requirements to the scale of the business, 
organizations, and governmental jurisdictions subject to regulation.'' 
To achieve that principle, the Act requires agencies to solicit and 
consider flexible regulatory proposals and to explain the rational for 
their actions. The Act covers a wide-range of small entities, including 
small businesses, not-for-profit organizations and small governmental 
jurisdictions.
    Agency must perform a review to determine whether a proposed or 
final rule will have significant economic impact on a substantial 
number of small entities. If the determination is that it will, the 
agency must prepare a regulatory flexibility analysis (RFA) as 
described in the Act.
    However, if an agency determines that a proposed or final rule is 
not expected to have a significant economic impact on a substantial 
number of small entities, section 605(b) of the 1980 act provides that 
the head of the agency may so certify and an RFA is not required. The 
certification must include a statement providing the factual basis for 
this determination, and the reasoning should be clear.
    A review of the Pacific traffic data shows that no small entities 
operate in Pacific oceanic airspace where this rule applies. The FAA 
has also examined the impact of this rulemaking on small operators of 
general aviation aircraft. The FAA database of U.S. registered aircraft 
operators shows that these airplanes are all operated by commuter or 
air taxi operators. Commuter or air taxi operators do not operate in 
Pacific oceanic airspace.
    The FAA has determined that there are reasonable and adequate means 
to accommodate the transition to RVSM requirements, particularly for 
general aviation operators (many of whom are small). As of May 1999, 
50% of the U.S. registered GA aircraft were approved for RVSM 
operations based on the NAT application of RVSM.
    The FAA conducted the required review of this proposal and 
determined that it would not have a significant economic impact on a 
substantial number of small entities. Accordingly, pursuant to the 
Regulatory Flexibility Act, 5 U.S.C. 605(b), the Federal Aviation 
Administration certifies that this rule would not have a significant 
impact on a substantial number of small entities.

International Trade Impact Statement

    The provisions of this proposed rule would have little or no impact 
on trade for U.S. firms doing business in foreign countries and foreign 
firms doing business in the United States.

Federalism Implications

    The regulations proposed herein would not have a substantial direct 
effect on the State, on the relationship between the national 
government and the States, or on the distribution of power and 
responsibilities among the various levels of government. Therefore, in 
accordance with Executive Order 12612, it is determined that this 
proposal would not have sufficient federalism implications to warrant 
the preparation of a Federalism Assessment.

Paperwork Reduction Act of 1995

    The reporting and record keeping requirements associated with this 
rule remain the same as under the current rules and have previously 
been approved by the Office of Management and Budget under the 
provisions of the Paperwork Reduction Act of 1980 (Pub. L. 96-511) and 
have been assigned OMB Control Number 2120-0026. The FAA believers that 
this rule does not impose any additional record keeping or reporting 
requirements.

Unfunded Mandates Reform Act of 1995 Assessment

    Title II of the Unfunded Mandates Reform Act of 1995 (the Act), 
enacted as Pub. L. 104-4 on March 22, 1995, requires each Federal 
agency, to the extent permitted by law, to prepare a written assessment 
of the effects of any Federal mandate in a proposed or final agency 
rule that may result in the expenditure by State, local, and tribal 
governments, in the aggregate, or by the private sector, of $100 
million or more (adjusted annual for inflation) in any one year. 
Section 204(a) of the Act, 2 U.S.C. 1534(a), requires the Federal 
agency to develop an effective process to permit timely input by 
elected officers (or their designees) of State, local, and tribal 
governments on a proposed ``significant intergovernmental mandate.'' A 
``significant intergovernment mandate'' under the Act is any provision 
in a Federal agency regulation that would impose an enforceable duty 
upon state, local, and tribal governments, in the aggregate, of $100 
million (adjusted annually for inflation) in any one year. Section 203 
of the Act, 2 U.S.C. 1533, which supplements section 204(a), provides 
that before establishing any regulatory requirements that might 
significantly or uniquely affect small governments, the agency shall 
have developed a plan that, among other things, provides for notice to 
potentially affected small governments, if any, and for a meaningful 
and timely opportunity to

[[Page 37024]]

provide input in the development of regulatory proposals.
    This proposed rule does not contain a Federal intergovernmental and 
private sector mandate that exceeds $100 million a year, therefore, the 
requirements of Title II of the Unfunded Mandates Reform Act of 1995 do 
not apply.

International Civil Aviation Organization and Joint Aviation 
Regulations

    In keeping with U.S. obligations under the Convention on 
International Civil Aviation Organization (ICAO), it is FAA policy to 
comply with ICAO Standards and Recommended Practices (SARP) to maximum 
extent practicable. The operator and aircraft approval process was 
developed jointly by the FAA and the JAA under the auspices of NATSPG. 
The FAA has determined that this amendment does not present any 
difference.

Environmental Analysis

    FAA Order 1050.1D defines FAA actions that may be categorically 
excluded from preparation of a National Environmental Policy Act (NEPA) 
environmental assessment or environmental impact statement. In 
accordance with FAA Order 1050.1D, appendix 4, paragraph 4(j), 
regulations, standards, and exemptions (excluding those, which if 
implemented may cause a significant impact on the human environment) 
qualify for a categorical exclusion. The FAA proposes that this rule 
qualifies for a categorical exclusion because no significant impacts to 
the environment are expected to result from its finalization or 
implementation.

Energy Impact

    The energy impact of this proposed rule has been assessed in 
accordance with the Energy Policy and Conservation Act (EPCA) and 
Public Law 94-163, as amended (42 U.S.C. 6362). It has been determined 
that this proposed rule is not a major regulatory action under the 
provisions of the EPCA.

List of Subjects in 14 CFR Part 91

    Air traffic control, Aircraft, Airmen, Airports, Aviation safety, 
Reporting and recordkeeping requirements.

The Proposed Amendment

    For the reasons discussed in the preamble, the Federal Aviation 
Administration proposes to amend part 91 of Title 14 of the Code of 
Federal Regulations (14 CFR part 91) as follows;

PART 91--GENERAL OPERATING AND FLIGHT RULES

    1. The authority citation for part 91 continues to read as follows:

    Authority: 49 U.S.C. 106(g), 40103, 40113, 40120, 44101, 44111, 
44701, 44709, 44711, 44712, 44715, 44716, 44717, 44722, 46306, 
46315, 46316, 46502, 46504, 46506-46507, 47122, 47508, 47528-47531.

    2. Part 91, appendix G, is amended by revising Section 8 to read as 
follows:

Appendix G to Part 91--Operations in Reduced Vertical Separation 
Minimum (RVSM) Airspace

* * * * *

Section 8. Airspace Designation

    (a) RVSM may be applied in the NAT in the following ICAO Flight 
Information Regions (FIRs): New York Oceanic, Gander Oceanic, 
Sondrestron FIR, Reykjavik Oceanic, Shanwick Oceanic, and Santa 
Maria Oceanic.
    (b) RVSM may be applied in the Pacific in the following ICAO 
Flight Information Regions (FIRs): Anchorage Arctic, Anchorage 
Continental, Anchorage Oceanic, Auckland Oceanic, Brisbane, 
Edmonton, Honiara, Los Angeles, Melbourne, Nadi, Naha, Nauru, New 
Zealand, Oakland, Oakland Oceanic, Port Moresby, Seattle, Tahiti, 
Tokyo, and Vancouver.
    (c) RVSM may be effective in the Minimum Navigation Performance 
Specification (MNPS) airspace within the NAT. The MNPS airspace 
within the NAT is defined by the volume of airspace FL 285 and FL 
420 extending between latitude 27 degrees north and the North Pole, 
bounded in the east by the eastern boundaries of control areas Santa 
Maria Oceanic, Shanwick Oceanic, and Reykjavik Oceanic and in the 
west by the western boundaries of control areas Reykjavik Oceanic, 
Gander Oceanic, and New York Oceanic, excluding the areas west of 60 
degrees west and south of 38 degrees 30 minutes north.

    Issued in Washington, DC, on June 30, 1999.
L. Nicholas Lacey,
Director, Flight Standards Service.
[FR Doc. 99-17360 Filed 7-7-99; 8:45 am]
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