NTSB Press Release

National Transportation Safety Board
Office of Public Affairs


NTSB RECOMMENDS REDESIGNED OVERWING EXITS, BETTER PASSENGER SAFETY BRIEFINGS, AND IMPROVED SLIDE MAINTENANCE PROGRAMS AS A RESULT OF AIRLINE CABIN EVACUATION STUDY

June 27, 2000

Washington D.C. - The National Transportation Safety Board today made recommendations to the Federal Aviation Administration to require easy opening and automatically stowing, Type III overwing exits on all newly manufactured aircraft. In addition to the new Type III exits, the Board also recommended further study on the effect of different exit row widths on passenger egress. The Board's report is the result of an in-depth examination of airline evacuations over a 16- month period from September 1997 through January 1999. During the study the Board investigated 46 evacuations of scheduled air carriers. The evacuations occurred as a result of both accidents and incidents, and on average, an evacuation occurred every 11 days during the period.

The study examined several safety issues including certification issues related to airplane evacuations; the effectiveness of evacuation equipment; the adequacy of air carrier guidance and Airport Rescue and Firefighting (ARFF) training; and communication during an evacuation.

Based on data collected, the Board concluded that passengers continue to have problems opening overwing exits and stowing the hatch. In the report's findings, the Board noted that the operation of the hatch is not intuitively obvious to most passengers. Much of the difficulty with the hatch results from the passengers' lack of understanding of proper evacuation procedures. Fifty percent of the exit row passengers interviewed for the study reported that they had not read the safety briefing card nor had they paid attention to the flight attendants' safety briefing. To combat this problem the Board recommended a new type of automatically stowing overwing hatch be required on newly manufactured passenger aircraft. The Board also recommended that exit row passengers receive a pre-flight personal briefing on what to do in the event of an evacuation.

In a related finding the Board noted that despite various techniques, the majority of passengers continue to ignore pre-flight safety briefings. Recommendations were made to explore more effective methods and new technologies to convey safety information to all passengers.

Based on evacuation studies conducted at the Civil Aeromedical Institute (CAMI) the FAA determined that an exit row width of 13 inches provides the same passenger egress benefit as a 20-inch exit width. The Evacuation Study, however, found flaws with the FAA's research on exit row width. The Board recommended the completion of additional research on exit row width and hatch removal to more adequately reflect conditions during an evacuation.

A further review of evacuation exits found problems with the reliability of emergency slides. In 37% of the evacuations where slides were deployed, there were problems with at least one slide. The problems ranged from slides that were difficult to deploy, or had to be manually inflated, to slides that could not be inflated at all. Stating that, "problems with slides in 37% of evacuations is unacceptable," the Board reiterated its 1999 recommendations (A-99-100, and A-99-101) to the FAA regarding airline maintenance programs for emergency evacuation systems.

In its review of evacuation communication and procedures the Board noted that passengers who attempt to evacuate an airplane with their carry-on baggage continue to pose a problem for flight attendants. In at least one evacuation the Board found that flight attendants had confiscated carry-on baggage from evacuating passengers and piled it against an unopened, usable exit. The Board made recommendations for flight attendants' training to address techniques for handling passengers who do not listen to flight attendant's instructions.

The report also revealed communication issues between cabin crew and flight crew with regard to initiating an evacuation. In several evacuations the cabin crew reported that the flight crew had not adequately communicated the nature of the emergency or the need to evacuate the aircraft. As a solution, periodic joint evacuation exercises involving flight crews and flight attendants, as well as the installation of independently powered evacuation alarms were recommended in the report.

A complete listing of the conclusions and recommendations made in the Evacuation Study can be found on the NTSB website at www.ntsb.gov. The Evacuation Study will also be available on the website in several weeks. When available, paper copies of the study can be purchased from the National Technical Information Service (800) 553-NTIS.

NTSB Office of Public Affairs: (202) 314-6100

 

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The National Transportation Safety Board (NTSB) is an independent federal agency charged with determining the probable cause
of transportation accidents, promoting transportation safety, and assisting victims of transportation accidents and their families.