[Federal Register Volume 67, Number 86 (Friday, May 3, 2002)]
[Proposed Rules]
[Pages 22363-22366]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 02-10947]


 ========================================================================
 Proposed Rules
                                                 Federal Register
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 This section of the FEDERAL REGISTER contains notices to the public of 
 the proposed issuance of rules and regulations. The purpose of these 
 notices is to give interested persons an opportunity to participate in 
 the rule making prior to the adoption of the final rules.
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 

  Federal Register / Vol. 67, No. 86 / Friday, May 3, 2002 / Proposed 
Rules  

[[Page 22363]]



DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Parts 25 and 121

[Docket No. 28061, Notice No. 95-1]
RIN 2120-AF01


Revised Access to Type III Exits

AGENCY: Federal Aviation Administration (FAA), DOT.

ACTION: Notice of proposed rulemaking (NPRM); withdrawal.

-----------------------------------------------------------------------

SUMMARY: The FAA is withdrawing a previously published NPRM that 
proposed to adjust requirements for access to Type III emergency exits 
(typically smaller over-wing exits) in transport category airplanes 
with 60 or more passenger seats. These adjustments reflected the 
results of additional testing by the FAA's Civil Aeromedical Institute 
(CAMI) conducted after the standards had been adopted. We are 
withdrawing the document because CAMI research on the issues is still 
ongoing and the Aviation Rulemaking Advisory Committee (ARAC) is 
currently considering a recommendation for a harmonized proposal on the 
issues addressed by Notice No. 95-1. ARAC will make its recommendation 
after completion of a FAA research program to study access to Type III 
exits. The FAA has determined that it should wait and see if some 
future regulatory action including the broader scope of this harmonized 
proposal would better serve the public interest.

FOR FURTHER INFORMATION CONTACT: Jayson Claar, Transport Airplane 
Directorate, Airframe and Cabin Safety Branch, Federal Aviation 
Administration, 1601 Lind Avenue SW, Renton, WA 98055; telephone (425) 
227-2194.

SUPPLEMENTARY INFORMATION:

Background

    On May 4, 1992, the FAA published a final rule (Amendment Nos. 25-
76 and 121-228) which set standards for access to Type III emergency 
exits in transport category airplanes with 60 or more passenger seats 
(57 FR 19220). These standards were the result of testing conducted by 
the FAA's Civil Aeromedical Institute and were intended to improve the 
ability of occupants to evacuate an airplane under emergency 
conditions. CAMI conducted further testing as time and resources became 
available, and the FAA subsequently proposed adjustments to those 
standards in Notice No. 95-1, published on January 30, 1995 (60 FR 
5794).
    Part 25 of Title 14 of the Code of Federal Regulations defines a 
number of different types of passenger emergency exits for use in 
transport category airplanes. As defined in Sec. 25.807(a)(3), a Type 
III exit must have an opening not less than 20 inches wide by 36 inches 
high. It need not be rectangular in shape, provided a rectangle of 
those dimensions can be inscribed within the opening. The corner radii 
must not exceed one-third the width of the exit. The step-up distance 
inside the cabin must not exceed 20 inches. Type III exits are 
typically located over the wing; when so located, the step-down to the 
wing must not exceed 27 inches. Type III exits are typically removable 
hatches, but they may be hinged or tracked doors. They are sometimes 
referred to as ``window exits.''
    CAMI tested various exit configurations with three-seat rows to 
obtain a more comprehensive understanding of effects of passageway 
widths and offsets from the exit opening. For these tests, CAMI used 
the same test fixture as that used for the tests conducted prior to the 
adoption of Amendment 25-76. It consisted of the fuselage of a Douglas 
C-124 airplane with seats and other equipment installed to represent an 
airline airplane in all aspects relevant to the tests. The test methods 
and procedures used for these tests were similar to those used during 
the earlier series of tests. And, as in the earlier tests, the purpose 
was to measure, on a comparative basis, the effectiveness of the 
features of an airplane when used in a typical, reasonable manner. The 
purpose was not to measure the performance of any particular group of 
test subjects, nor to evaluate the total elapsed time needed to 
evacuate an airplane under any specific crash scenario. The CAMI tests 
were intended to evaluate comparatively the effects of passageway width 
and seat-row encroachment on total time for egress through Type III 
exits.
    Testing determined that the total egress times with 13-, 15-, and 
20-inch passageways were nearly identical. In contrast, the total 
egress times for the narrower 10- and 6-inch passageways, were much 
greater. These tests also measured the effect of centerline offset; 
i.e., the distance that the centerline of the passageway is offset from 
the centerline of the exit. The tests showed that 13-inch passageways 
with centerline offsets up to 6\1/2\ inches provide egress capability 
equal to that of 20-inch passageways with the 5-inch maximum offset 
allowed by the current rule. Tests conducted with a group of older 
subjects found that egress times were slower for older occupants, but 
the relative merits of the various passageway widths and offsets were 
similar.
    Testing also proved consistent with a series of evacuation tests 
that had been conducted in the United Kingdom, generally referred to as 
the ``competitive tests.'' Although providing more space adjacent to an 
exit would intuitively seem to improve the evacuation flow rate, the 
competitive tests showed that providing more space does not always 
improve the flow rate and may, in some instances, actually prove to be 
counterproductive. This is primarily because evacuees sometimes form 
multiple files when additional space is available and compete for 
access to the exit, rather than pass through it in one orderly file. It 
must be emphasized that the competitive tests were conducted for a 
different purpose than either the CAMI tests or the tests conducted 
prior to the adoption of Amendment 25-76. The competitive behavior 
tests were conducted to analyze human behavior under emergency 
conditions, while the FAA tests were to compare the capability of 
various configurations when used in a typical, reasonable manner. 
Nevertheless, the CAMI tests were consistent with the competitive 
tests, in that a 13-inch passageway was shown to provide an egress 
capability as good as that provided by a 20-inch passageway.
    In view of the results of the CAMI tests, the FAA determined that 
an

[[Page 22364]]

unobstructed passageway 13 inches wide, with its centerline offset no 
more than 6\1/2\ inches from the centerline of the exit, provides a 
level of safety equal to that provided by the 20-inch passageway 
specified in Sec. 25.813(c)(1)(i). Had data from those tests been 
available prior to the adoption of Amendment 25-76, the FAA would have 
specified 13 inches minimum width and 6\1/2\ inches maximum offset at 
that time. Notice No. 95-1 proposed to amend Sec. 25.813(c)(1)(i) to 
specify 13 inches minimum width and a maximum centerline offset of 6\1/
2\ inches for rows with three seats.
    Notice No. 95-1 would also have proposed the correction of an 
editorial error by amending Sec. 121.310(f)(3)(iii) to incorporate 
Sec. 25.813(a)(2) by reference. Further, the incorporation by reference 
of Sec. 25.813(c) in Sec. 121.310(f)(3)(iii) would have been clarified 
by replacing the reference to Sec. 25.813(c) in its entirety with a 
reference to only Secs. 25.813(c)(1) and (3).
    The NPRM invited public comment to assist the FAA in the rulemaking 
process. The comment period closed on May 1, 1995.

Discussion of Comments

    Two aircraft manufacturers, a consumer advocate, an organization 
representing European aircraft manufacturers, and three individuals 
responded to Notice No. 95-1. In addition, an organization representing 
U.S. airlines and another representing three airline flight attendant 
unions also responded. One foreign airworthiness authority also 
reviewed the notice, but submitted no comments.
    One manufacturer concurred with the notice, concluding that it 
would lessen the overly tight pitch requirement for seats adjacent to 
Type III exits. The commenter also commended CAMI for its study and 
noted that it will alleviate a potential financial burden on the 
aircraft industry while still maintaining the high level of safety that 
currently exists. The other manufacturer concurred, but offered no 
further comment.
    The consumer advocate opposed requiring the minimum passageway 
width to be only 13 inches, claiming it would be detrimental to 
passenger safety, would ignore the critical lessons of past fatal 
accidents, and would offer no demonstrable benefits. The commenter 
offered no evidence to support those opinions, and they are 
contradicted by evidence outlined in the preamble of Notice No. 95-1.
    A number of commenters questioned the validity of the CAMI testing. 
Generally, they believe the study to be unrealistic because it did not 
represent an actual crash. They noted that there was no fire, smoke or 
toxic fumes, no panic, subjects did not represent a cross-section of 
the flying public, the competitive behavior that might be exhibited in 
an actual crash was not experienced, and the exit hatch was not 
required to be removed by one of the passengers. These comments would 
have been applicable if the purpose of the testing had been to measure 
how passengers would respond in an actual crash. However, the purpose 
of these tests was not to evaluate the performance of passengers. The 
purpose was to determine the minimum passageway width and maximum 
centerline offset that would allow egress equivalent to that allowed by 
a 20-inch passageway with a 5-inch offset. The CAMI tests targeted 
airplane configuration--not vision, motivation, variations in passenger 
behavior, airplane crashes, or any combination of those variables.
    It must be noted that evacuation demonstrations are not conducted 
under actual conditions of fire, smoke, or toxic fumes for two basic 
reasons. The first and foremost consideration is the safety and well-
being of the test subjects. Testing under those conditions could very 
likely result in unnecessary serious injuries to the test subjects. 
Second, the purpose of such demonstrations is not to show that test 
subjects can evacuate an airplane in a specified time under all 
possible emergency conditions. Due to the myriad of different possible 
crash scenarios that could occur and the varying need for urgency, it 
would be impossible to develop a series of tests that would encompass 
all of those possible conditions. Instead, the evacuation capability of 
an airplane is evaluated under standard, repeatable conditions. By 
testing under such controlled, consistent conditions, the evacuation 
capability of an airplane can be compared with that of the other 
airplanes that have been tested previously under the same conditions. 
Through this indirect means, the evacuation capability of the airplane 
is related to the accidents that have actually occurred with those 
earlier airplanes. The evacuation capability of an airplane under the 
variables cited by the commenters is, therefore, considered without 
exposing test subjects to intolerable risk of serious injury.
    A second set of tests conducted with older subjects was invalid in 
certain respects because some of the test subjects stepped on the seat 
cushions rather than fully utilizing the passageway. One commenter 
believes that older passengers adopted this practice because the 
passageway was too narrow for older passengers who are not as agile. 
Actually, this practice was the result of an inadvertent incorrect 
instruction given by a flight attendant rather than an ingenious 
response to insufficient passageway space, as suggested by the 
commenter. The video records of the testing clearly show that the older 
test subjects did not step on the seat cushions simply because the 
passageway lacked sufficient width at floor level, nor that they had 
any difficulty with a 13-inch wide passageway for that matter. In fact, 
all of the video records of testing of both 13-inch and 20-inch 
passageways demonstrated that the subjects generally lined up in the 
passageway awaiting their turn to pass through the exit. In other 
words, the egress pace was determined not by the width of the 
passageway, but by the rate of movement through the exit.
    Two commenters referred to the tragic US Air accident at Los 
Angeles, California, in 1991. In that regard, one quoted from a 
document entitled, ``Eighteenth Report by the Committee on Government 
Operations in 1992.'' According to the commenter, the document states, 
in part, ``if the passageway to the overwing exit had been just a few 
inches wider, more people might have escaped.'' While that statement 
would intuitively seem to be true, there were mitigating circumstances 
involved in the evacuation of that airplane. In any event, the 
reference to that accident is not relevant. Since the passageways 
leading to the Type III exits in the USAir airplane were approximately 
6 to 6\1/2\ inches wide, the proposed minimum passageway width of 13 
inches is approximately twice as great.
    The organization representing U.S. airlines forwarded responses 
received from three of their member airlines. One airline supported the 
proposed changes without further comment. In addition to supporting the 
changes that were proposed, two other airlines raised issues concerning 
previously granted deviations from the requirements. Section 
121.310(f)(3)(iv) permits the FAA to authorize deviations from 
Sec. 25.813 that allow recline on the inboard seats only. This 
concession applies only to existing airplanes. Later airplane designs 
must comply with Sec. 25.813 as a condition of type certification. 
Accordingly, no change to either Sec. 25.813 or Sec. 121.310 is 
warranted.
    The organization representing European aircraft manufacturers 
described a series of tests conducted

[[Page 22365]]

later at the Cranfield Institute in the United Kingdom. (This is the 
same facility in which the previously mentioned ``competitive tests'' 
were conducted.) According to the commenter, the later tests were 
conducted using the same protocol as the CAMI tests, but with a 
passageway as narrow as 10 inches and 9 inches offset. Based on this 
test series, the commenter believes that a passageway only 10 inches 
wide provides the same level of safety as a wider passageway. The 
commenter implied that Sec. 25.813(c)(1)(i) should, therefore, be 
amended to require only a passageway 10 inches wide with three-abreast 
seat rows, rather than 13 inches wide as proposed in Notice No. 95-1. 
Although the results of this series of tests would appear to be 
inconsistent in this regard with the results of both the FAA testing 
and testing conducted earlier at Cranfield, adopting a minimum width of 
less than 13 inches would be beyond the scope of the notice, even if 
these test results would justify such a change.
    The same commenter referred to a pending proposed amendment to 
Joint Aviation Requirements for Large Aeroplanes-25 (JAR-25) concerning 
access to Type III exits. The commenter noted that part 25 will not 
contain all of the requirements concerning access to Type III exits 
being considered for inclusion in JAR-25 and believes that the NPRM 
should not proceed to the final rule stage until the standards of the 
two codes can be harmonized.
    This comment underscores the central reason for withdrawal of 
Notice No. 95-1. The FAA is involved in eliminating unnecessary 
differences between the Federal Aviation Regulations and the Joint 
Aviation Requirements (JAR) used in European countries, through an 
ongoing cooperative harmonization process that includes Joint Aviation 
Authorities (JAA) and Transport Canada. JAR-25 is the code of standards 
adopted by the airworthiness authorities of a number of European 
countries for type certification of transport category airplanes. It is 
based on, and is generally similar to, part 25; however, there are 
detail differences. The FAA's desire to harmonize the two codes has 
dictated their efforts in many areas of current regulatory activity. 
ARAC's Occupant Safety Issues Area, formerly known as the Emergency 
Evacuation Issues Area, is working on a recommendation for a harmonized 
proposal on the issues addressed by Notice No. 95-1. ARAC will make its 
recommendation after completion of a FAA research program to study 
access to Type III exits.
    Subsequent to the close of the comment period and analysis of the 
timely comments, comments were received from three additional consumer 
advocacy groups and two labor organizations. Each opposed requiring the 
minimum passageway width to be only 13 inches. Like the consumer 
advocate that had commented earlier, two of the consumer advocacy 
groups claimed that requiring a minimum passageway width of 13 inches 
would be detrimental to safety and would offer no demonstrable 
benefits. Those commenters offered no evidence to support those 
opinions; and, as discussed above, they are contradicted by evidence 
outlined in the preamble of Notice No. 95-1.
    The third late commenter also opposed requiring passageways to be 
only 13 inches wide for essentially the same reasons as those given by 
earlier dissenting commenters. Many of the points raised by that 
commenter are addressed in response to the timely comments; however, 
that commenter did raise additional issues.
    The commenter questioned the effectiveness of adjacent Type III 
exits. Although not directly related to this rulemaking, the FAA has 
initiated separate rulemaking to reduce the combined passenger rating 
of such exits when they are located within three passenger seat rows of 
each other.
    The commenter characterized the CAMI tests as ``manipulating 
research data to suggest that 13 inches would produce the same 
benefit.'' Contrary to the commenter's characterization, the tests do 
not represent ``manipulation'' of the earlier research data on which 
Amendment 25-76 was based. In fact, the CAMI tests confirm the results 
of the first test series `` passageways that are 20 inches wide do 
provide egress capability superior to that provided by passageways that 
are 10 inches wide. (This refers, of course, to installations of three-
seat rows. Ten-inch passageways were found during the earlier testing 
to provide the same superior egress capability when two-seat rows are 
installed. No change was proposed in Notice No. 95-1 to the standards 
for access when two-seat rows are provided.) Since no testing of 
intermediate passageway widths was conducted during the first series, 
there were no data pertaining to those widths from the first series to 
``manipulate.'' The egress capability provided by intermediate 
passageway widths was unknown at the time Amendment 25-76 was adopted, 
and the CAMI tests merely provided data for those intermediate 
passageway widths.
    Finally, the commenter asserted that data from the testing 
conducted both in this country by CAMI and in the United Kingdom at 
Cranfield show that 20-inch passageways provide superior egress 
capability. Contrary to the commenter's assertion, the data from the 
recent CAMI tests do, in fact, show that 13-inch passageways provide 
egress capability equal to that provided by 20-inch passageways. Also 
contrary to the commenter's assertion, the competitive behavior tests 
conducted at Cranfield do not show that 20-inch passageways provide 
superior egress capability to those 13 inches in width.
    The fourth late commenter opposed requiring passageways only 13 
inches in width and questioned the validity of the test procedures. 
Most of the points raised by the commenter were raised by other 
dissenting commenters and addressed above. There were, however, a 
number of additional points raised.
    The commenter noted that Advisory Circular 25-17 describes the 
Latin Square test method and implies that the inclusion of that test 
method in the advisory circular means other test methods are invalid. 
Advisory Circulars describe acceptable methods, but not the only 
acceptable methods, for complying with regulations. Contrary to the 
commenter's implication, the method used in the CAMI tests is also an 
established and highly respected scientific method to ensure that the 
test results are not clouded by variations in test subject performance. 
The Latin Square test method was not used in the CAMI tests primarily 
because it would have required almost twice as many test subjects to 
test the same configurations.
    The commenter also quoted a statement made by the National 
Transportation Safety Board (NTSB) and asserts the statement means the 
NTSB opposes requiring these passageways to only be 13 inches wide. 
According to the commenter, the NTSB states in the accident 
investigation report for the USAir accident at Los Angeles in 1991, 
``The Safety Board believes that a continuous access path of no less 
than 20 inches, as demonstrated by tests, is preferable to removing the 
seat adjacent to the exit or removing the seat and having a 20-inch or 
less access path.'' The NTSB was actually referring to the relative 
merits of the two proposed configurations that were later adopted in 
Amendment 25-76. The NTSB would not have commented on the merits of a 
passageway 13 inches in width because that was not one of the 
configurations proposed then and there were no applicable test data 
available then to prove or disprove its merits. As noted above, there 
were no specific standards for access to Type III exits at the time of 
the USAir accident; however, the passageways of that airplane were

[[Page 22366]]

approximately 6 to 6\1/2\ inches in width. The NTSB did not submit any 
comments concerning the changes proposed in Notice No. 95-1 and has not 
made any formal recommendations concerning the width of passageways 
leading to Type III exits.
    The issues raised by the last late commenter were all addressed in 
response to other commenters; however, that commenter questioned the 
use of the term ``clear path'' in the graph of pathway widths versus 
egress time contained in the preamble to Notice No. 95-1. ``Clear 
path'' was used in the preliminary graph of the results of the second 
test series to denote a configuration in which the forward-most edge of 
the unobstructed passageway was no farther forward than the forward-
most edge of the emergency exit. It was recognized that the term could 
cause confusion, so the test configurations were described in terms of 
centerline offset or seat encroachment in the final reports.

Reason for Withdrawal

    CAMI is presently doing further studies on access to Type III 
exits. The withdrawal of Notice No. 95-1 enables future rulemaking 
action that will be able to benefit from this ongoing research and 
produce a more accurate, fresh perspective on the issues.
    In addition, the FAA is involved in eliminating unnecessary 
differences between the Federal Aviation Regulations and the Joint 
Aviation Requirements used in European countries. This is an ongoing 
process of aligning its regulations with those of the Joint Aviation 
Authorities (JAA) known as harmonization. Our desire to harmonize the 
two codes has dictated our efforts in many areas of current regulatory 
activity. ARAC's Occupant Safety Issues Area, formerly known as the 
Emergency Evacuation Issues Area, is working on a recommendation for a 
harmonized proposal on the issues addressed by Notice No. 95-1. ARAC 
will make its recommendation after completion of a FAA research program 
to study access to Type III exits. Continuing industry input through 
the ARAC process will contribute to a more complete analysis of the 
issues. Therefore, we have determined that it would be better to wait 
and see if some future regulatory action including the broader scope of 
this harmonized proposal would better serve the public interest.

Withdrawal of Proposed Rule

    Withdrawal of Notice No. 95-1 does not preclude the FAA from 
issuing another NPRM on the subject matter in the future or committing 
the agency to any future course of action. To achieve harmonization 
goals, we will make any necessary changes to the Code of Federal 
Regulations through a future NPRM with opportunity for public comment. 
Therefore, the FAA withdraws Notice No. 95-1, published on January 30, 
1995 (60 FR 5794).

    Issued in Washington, DC, on April 26, 2002.
John Hickey,
Director, Aircraft Certification Service (AIR-1).
[FR Doc. 02-10947 Filed 5-2-02; 8:45 am]
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