Friday, March 27, 2015

Black Swan

Issue 6 
Prepared for: European Aviation Safety Agency

... The significance of this issue [emergency access to the flightdeck] depends on the likelihood of an event where all three risks below exist:
 - there is an emergency situation which requires crew access from the cabin to the flightdeck, and
 - the flight crew are unable to unlock the flightdeck door from the flightdeck by any method available to them, and
 - the emergency means for cabin crew to access the flightdeck does not function.

 Procedures have been used to prevent incapacitation of all flight crew due to common factors such as food or drink poisoning. There could be other factors such as hypoxia, cabin air contamination with noxious fumes or smoke/fire, or windscreen failure (e.g. due to maintenance error or bird impact exceeding the standards provided by the airworthiness requirements. The risk of the incapacitation of all flight crew is considered to be small, but not non-existent (see Appendix 2 for more discussions on flight crew incapacitation). However, there is still a more conceivable risk where one flight crew leaves the flight deck (e.g. to go to the lavatory) and the other flight crew in the flight deck becomes incapacitated. If the emergency means to enter the flightdeck from the cabin does not have a high degree of reliability, the consequences could be catastrophic. Another conceivable risk is where one of the flight crew becomes incapacitated and the other flight crew requires assistance from the cabin crew, but the flight crew is unable to unlock the door from his station for any reason. There have been reports of pilots being locked out of the flight deck5 , with the widely publicised occurrence on a CRJ-100 on a flight from Ottawa to Winnipeg in 26 August 2006.

For more Germanwings foreshadowing, or lack thereof, use your search engine of choice for the term FAR 25.772(c).

UPDATE: The above discussion brings out one important point. The air regulators are now saying that the no-one alone in the flight deck rule that was already partially on the books is the response to the Germanwings case. But that rule itself emerged as a substitute for the originally proposed requirement that there be emergency access to the flightdeck from the cabin even if the door is locked. MH 370 may have met the requirement of both pilots on the flightdeck and still crashed. The issue is after realizing that the plane is under malign control, there should be a way to intervene from the cabin.

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