The Basics
The "legroom" in the overwing exit row on narrow
body aircraft becomes an evacuation pathway that leads to a plug-type exit (see
14 CFR 25.807). The passengers that sit in these rows are instructed, in the
event of an emergency, to remove the hatch manually, and either throw it onto
the wing or lay it across the seat row inside the aircraft. However, documented
difficulties in removing and stowing these hatches have slowed evacuations,
costing lives. At issue is, what is the optimum pathway width and seating
configuration that will best facilitate smooth and fast evacuations at the
overwing?
The current federal aviation regulation (14 CFR 25.813)
for three-abreast seating requires either: (1) a minimum 20" pathway leading
to a single hatch; or (2) twin 6" pathways leading to a pair of hatches
with the "outboard" seat removed. (The outboard seat is located
adjacent to the fuselage.) A minimum 10" pathway is deemed acceptable for
a two-seat row.
A 1995 paper published by the Civil Aeromedical Institute
(CAMI) convinced the FAA to allow airlines to provide a 13" evacuation
pathway at a three-seat row, even though the rule says 20". This reduction
saves the airlines money because in some cases, it enables them to install
another row of revenue-generating seats. However, it could also cost lives
because it only leaves a narrow evacuation pathway.
The results of this CAMI research project should never
have been applied to the real world because the test subjects – unlike airline
passengers – did not have to open the overwing hatch and dispose of it; the
researchers did it for them. In the real world, passengers sometimes drop the
hatch on the floor of the aircraft, reducing the width of the evacuation
pathway by at least 8", which can slow or stop an evacuation.
Nonetheless, in 1995, the FAA proposed that
their 20" rule be amended down to 13". Then, in 2002, they withdrew
that proposal.
From April 2000 until December 2002, a FAA
working group, composed largely of industry members, deliberated on appropriate
language for a new rule that would apply in the US, Europe, and Canada. AFA and
other members representing unions and passengers, proposed that the regulators:
(1) keep the 20" rule; (2) disallow the twin 6" pathway configuration;
and (3) require easy-to-open hinged hatches at the overwing, as per the NTSB
recommendation. These union and passenger groups would not object to a 13"
pathway if and only if an outward opening, hinged hatch is required
because it would no longer be necessary to provide floor space for the
disposable hatch. In contrast, the airlines and manufacturers proposed that the
regulators allow the current plug-type hatch in a 13" pathway or twin
6" pathways, even though this is not supported by any safety research.
We expected the regulators to rule on this
issue in 2004, but so far, no news. Regulations must provide adequate
evacuation space for realistic emergency conditions; to do otherwise
jeopardizes the lives of people who may need to escape at the overwing.
AFA activity and hot topics
Dec 17, 2002 Explanatory
appendix to accompany position statement submitted by crewmember union and
passenger members of the FAA Cabin Safety Harmonization Working Group.
Apr 2002 AFA Position
on the Harmonization of FAR/JAR 25.813 (overwing seating and hatch
configurations) Association of Flight Attendants, AFL-CIO
Apr 24,
2000 Review of Type
III Emergency Exit Evacuation Research Edited by the International Transport
Workers' Foundation. Written by J. Anderson-Murawski, AFA. Submitted to FAA
Cabin Safety Harmonization Working Group.
References to news articles
Nov 5,
2001 Air Safety Week "Cramped
seating can 'trap' and 'trip' passengers during emergency evacuation"
July
23, 2001 BBC
Investigative News Program "4x4" Access to overwing exits (Series 1,
Program 1)
Nov 1,
2000 Air Safety Online "Singapore
Airlines crash survivors tried hatchets"
June
16, 1995 USAToday "Junk idea
of narrowing airline exit passages"
More information
May 4,
1992 Improved
Access To Type III Exits: Final Rule US Federal Aviation Administration, DOT.
Federal Register: 19220-19247 (14 CFR 25.813)
Nov 29,
1989. Aircraft Cabin Safety: Minutes of Evidence Testimony by Survivors' Campaign To Improve Safety
in Airline Flight Equipment (SCISAFE) given in the UK House of Commons, Session
1989-90.
Print
AFAposnApr02.doc