Safety Recommendation A-00-073

At the October 3, 2003, meeting, the FAA stated that it disagrees with this recommendation because it believes there is substantial excess evacuation capacity in airplanes with fewer than 44 seats; therefore, there would be little or no benefit from doing a partial evacuation demonstration in these aircraft.

The Safety Board continues to believe that the recommended action is needed. The Board notes that the partial evacuation demonstration is designed to evaluate airline procedures rather than equipment design. The Board believes that the recommended action is particularly needed on aircraft with fewer than 44 seats, such as the Beech 1900, which operates without a cabin crew, and on aircraft on which the first officer is expected to open a primary exit in the event of an emergency. A partial evacuation demonstration would discover procedures that might seriously delay the first officer's ability to open an emergency exit.

At the October meeting, the FAA suggested that it could conduct tests, not as a regulatory requirement, but as an evaluation of the need for the recommended action. The tests would involve a number of currently used passenger aircraft with fewer than 44 seats, including a number of aircraft that are operated without a flight attendant. During the meeting, it was determined that this recommendation could be classified "Closed-Acceptable Alternate Action" if the FAA could supply data from the testing, showing that on aircraft with fewer than 44 seats, the emergency exits could be opened and prepared for evacuation within 15 seconds when established airline procedures are used.

However, if the FAA could not supply this information, the recommendation would be classified "Closed--Unacceptable Action."

After the October meeting, the FAA advised Safety Board staff that, based on the excess evacuation capacity in aircraft with fewer than 44 seats, it does not believe it necessary or advisable to require a partial evacuation demonstration in these aircraft. The FAA has supplied no information regarding an evaluation of procedures to prepare the passenger cabin for evacuation on aircraft with fewer than 44 seats. Therefore, Safety Recommendation A-00-73 is classified "Closed--Unacceptable Action."

SWAT Meeting 10/3/03 Minutes attached Phyllis Anne Duncan, Manager, Technical Information and Communications Programs Branch, AFS-140 , FAA, 12/11/03 For A-00-73 IOU regarding supplying data to show there is no need for partial evac demos on aircraft with fewer than 44 seats, here is the IOU: Part 25 specifies that a Type 1 door measure at least 24" by 48", affording a passenger escape flow rate of 45 passengers in 90 seconds. The Beech 1900 has a Type 1 door measuring 27" by 52"--larger than the standard. Part 25 also specifies that a Type 4 exit (overwing exit) measure at least 19" by 26", affording a passenger escape flow rate of 9 passengers in 90 seconds.

The Beech 1900 has three overwing exits measuring 20" by 27-1/2"--again larger than the standard. Thus, the Beech 1900 exceeds a theoretical maximum passenger escape flow rate of 72 passengers in 90 seconds for an aircraft with a passenger cabin seating 19. This amounts to a safety allowance of more than 250% of that required by Part 25. Similar data apply for airplanes comparable to the Beech 1900, such as the Embraer 120 and the Jetstream 31.

The Safety Board acknowledges that regulations regarding the number of exits may result in a wide safety margin, but notes that these regulations will simply ensure the aircraft will likely pass the evacuation demonstration requirement. Although all aircraft must have sufficient exit capacity for their passenger loads, they sometimes do not pass the evacuation demonstration requirement, which indicates that relying on exit capacity alone is not sufficient to determine the maximum passenger load that an aircraft can safely carry and evacuate in an emergency.

The Board notes that airplanes certificated under Part 23, which often have fewer than 44 seats, require an evacuation demonstration even though Part 25 airplanes with fewer than 44 seats are not so required. The Board learned, as part of the investigation of a runway collision accident in Quincy, Illinois, involving a Beech 1900 aircraft on November 19, 1996, that a full-scale evacuation demonstration was conducted as part of the certification for the Beech 1900 under Part 23. It took more than 80 seconds to complete this full-scale evacuation demonstration on the Beech 1900.

The Board is aware of other aircraft with seating capacities around or fewer than 44 seats that had evacuation demonstration times greater than 80 seconds, bringing into question the large margin of excess capacity to which the FAA refers. The Board is also concerned that there is no requirement to demonstrate that cockpit crews of aircraft with fewer than 20 seats without a flight attendant can quickly open cabin exits in addition to their duties as flight crewmembers.

In its recommendation letter, the Safety Board expressed concern that existing regulations that exempt certain airplanes and operations because of passenger seating capacity are not consistent with the goal of providing "one level of safety" for all passenger-carrying commercial airplanes. The Safety Board disagrees with the FAA's belief that aircraft below some passenger capacity does not require full-scale or partial evacuation demonstration and asks the FAA to reconsider that position. Pending completion of the recommended actions, Safety Recommendations A-00-72 and A-00-73 are classified

Letter Mail Controlled 11/14/2000 4:39:44 PM MC# 2001688 The FAA addressed the issue of partial evacuation demonstrations during its regulatory review of the final commuter rule to bring scheduled passenger operations in airplanes of 10 or more passenger seats and all turbojets under the requirements of 14 CFR Part 121. The FAA determined that a requirement to conduct partial demonstrations for transport-category airplanes with fewer than 44 seats was not warranted because the specific design requirements of these airplanes ensure that passengers can evacuate quickly and safely.

To require partial evacuation demonstrations would not increase the level of safety already in place for these airplanes. I consider the FAA's action to be completed on this safety recommendation.