It beggars belief that in 2015 a pilot could seal the aircraft flight deck and deliberately kill everyone on board by re-programming the flight path into a mountain. This appears to have happened this week.
Aircraft have become technically very sophisticated, so much so that they are very close to take-off and landing unaided. As we know, this technique has been operating successfully with drones for at least 10 years. So what went wrong here?
911 was the trigger to fly with the flight deck door closed and the addition of security systems to prevent unauthorised entry. These measures included door strengthening and controls to lock from the flight deck any possibility of entry from the main cabin.Since this change occurred there have been no unauthorised entries into the flight deck cabin whether by terrorists or mentally disturbed people.
However over the past 12 years there have been 6-8 situations where pilot suicide either occurred or was suspected. Even in an Air New Zealand flight from Perth last year, the Captain restricted entry to the Co-Pilot for a short period due to a dispute they were having at the time. Hard to believe but apparently true.
An unknown number of airlines and flights introduced a rule that if the flight deck was to be manned by only one pilot at any time then a second person selected from the cabin crew was to be in attendance. It appears that where this rule has been applied there have been no incidents of pilot or co-pilot rogue behaviour.
Obviously there are disturbed pilots around the world who may 'flip' mentally and carry out an unbelievable act of terror for the passengers. The German airline has, amongst others, relied on psychological testing and an in-house reporting system on any suspicious behaviour. It was just not good enough for 150 people on this flight.
The spotlight should now be turned on airline management and on aircraft manufacturers. The switch used by the co-pilot allowed him to lock the door so much so that there was no method of entry from the outside. This system now has to be modified.
A suggested emergency system is the following. Introduce three sealed envelopes on all flights, each containing two digits of a six digit pin that will open the door. The pilot leaving the flight deck, for example to visit the toilet, must take the flight deck envelope with him or her. There are two other envelopes with cabin crew members, one of whom is temporarily inside the flight deck cabin during the pilots absence.
In an emergency of this nature these three sets of numbers make up the entry code to override the door lock. Coupled with this it should, as indicated above, be mandatory for a crew member to attend the flight deck on either pilot exiting for any reason.
The cost of these changes would be minimal. They should have prevented what seems to have happened to this aircraft, Flight 9525, Silk Air, Egypt Air, possibly Malaysian Air 370 and others. Would it 'open the door' to more terrorist attempts? Not with part of the code being carried inside the flight cabin.
Could a rogue pilot in the flight deck stop the cabin crew member from entering their part of the code? Possible but unlikely. Then there is the possibility of flight deck personnel being incapacitated by, say, an oxygen failure. Well that is a different problem with a different technical solution to ensure it doesn't happen.
There is now talk of GPS limits on altitude reduction or other restrictive controls over the aircraft. Even marshals on board and cameras up front as a deterrent. I disagree. Keep it simple stupid.