International numbers state that planes downed by pilot or co-pilot due to suicide are a rare but still possible occurrence.

In the United States such a safety procedure is standard (as of 9/11 - if I remember correctly). Why didn't the EASA think of that earlier?


closed as primarily opinion-based by FreeMan, Jan Hudec, GdD, Simon, fooot Apr 22 '15 at 14:22

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    $\begingroup$ Note. On 9/11, there were already 2 crew in the cockpit when they were taken over. $\endgroup$ – Simon Apr 22 '15 at 14:11
  • $\begingroup$ Oh wow thanks, I didn't know that. Do you have a document or an official statement that proves that? $\endgroup$ – Elena Apr 22 '15 at 14:19
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    $\begingroup$ Because of 9/11, the rule that cockpit door must be locked was introduced. And the two men rule went with that to handle situation when one of them is incapacitated (which does happen occasionally) so there is still somebody to open the door. It was relaxed when the emergency code that opens the door from outside unless rejected in some time limit was introduced. IIRC it was relaxed everywhere, provided the emergency entry code is available. $\endgroup$ – Jan Hudec Apr 22 '15 at 14:33
  • $\begingroup$ @Jan Hudec So 2 men cockpit rule in the US did go hand in hand with 9/11? Is that correct? $\endgroup$ – Elena Apr 22 '15 at 15:01
  • $\begingroup$ @Elena: Yes, but indirectly. It was only instantiated because the first door locks didn't have the emergency code. $\endgroup$ – Jan Hudec Apr 22 '15 at 17:13

Graveyard evolution; new advances are only pushed through when the existing situation is provably not safe.

Aviation history is rife with examples of safety measure being taken after an incident of accident that could have been prevented by that measure.

  • $\begingroup$ Thats what I thought. In their last update on cockpit rules they stated: "EASA publishes today a temporary recommendation for airlines to ensure that at least two crew, including at least one qualified pilot, are in the flight crew compartment at all times of the flight." Why the hell do they only recommend and not require, and why only temporary? They are a regulatory and executive agency - they should be much more stricter with that!!!! $\endgroup$ – Elena Apr 22 '15 at 14:04
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    $\begingroup$ @Elena Because hasty rule patching causes more harm than good (just ask your local legislative body). Many times there are unforeseen consequences to the rules. $\endgroup$ – ratchet freak Apr 22 '15 at 14:08
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    $\begingroup$ @Elena Because the EASA possibly does not come to the same conclusion the FAA or other CAAs came to and therefore only issued a temporary recommendation. Many, me included, will argue that the two-man cockpit rule is only changing things for the sake of change and purely cosmetic to show the public that actions are being taken (even though they are ineffective). $\endgroup$ – SentryRaven Apr 22 '15 at 14:09
  • $\begingroup$ @Sentry Raven so what kind of regulation can be enforced in order to prevent future plane accidents due to intervention by pilot or co-pilot? $\endgroup$ – Elena Apr 22 '15 at 14:18
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    $\begingroup$ @Elena To be brutally honest, none! There is no way to exclude 100% of all possible scenarios. You can work to minimize or eliminate the probability of some of the possible scenarios, but you will never create a 100% working solution for everything. Look at it this way: The door lock was introduced to keep intruders out of the cockpit. The copilot in GWI18G used that against the pilot. What would be the logical consequence? Remove the door lock! What does that open up again? Possible threat from external intruders! Too many possible threat to consider, so you focus on the most probable ones.. $\endgroup$ – SentryRaven Apr 22 '15 at 14:20

Because aviation procedures and rules develop from historical occurances.

In some cases, the actual occurance and the resulting change in procedures do not have anything in common or are not related, e.g. some will argue that the two-man rule would not have prevented 9/11. It is also being discussed that the two man rule would only have had a psychological effect to deter the pilot/copilot from deliberately crashing the plane (as in the Germanwings crash), some will argue that a pilot or co-pilot intent to deliberately crash the airplane will not be deterred by a flight attendant in the cockpit, who due to lack of flight education would not be able to counter the pilot's/copilot's input in the FMC/AP.

The cockpit door measures to deny unauthorized access to the cockpit were implemented because the threat was assumed to come from outside the cockpit. You cannot implement measures that will work against everything and every threat, internal or external. Hence why EASA (and this is only speculative, because we can't know for sure) did not implement a two-man rule and currently has not implemented one, the two-man rule is a airline SOP issue at the moment.


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