by expat » Mon Oct 13, 2014 10:51 pm
Modlerbob wrote:While watching a pbs NOVA report about the lost Malaysian B777 it was reported that the compartment containing all of the hardware for the flight computers is located below the main cabin floor with the access hatch in the passenger compartment. Locks for this hatch are optional and the Malaysian B777's don't have locks. All of the flight deck computers can be controlled from this compartment overriding cockpit commands and turning off the locator transponders. Also the oxygen bottles for the flight deck crew are in this compartment and the valves are there too. Even the locks for the flight deck door can be disabled. There is a you tube video made by a Brazilian pilot demonstrating all of this information.
This, to me, could pose a significant security breach if a potential hijacker just did a little homework. I don't know if other airliners are configured in the same way but I hope not.
I realise you are quoting a TV program who are always after the sensational angle , but I am not quite sure what is meant by "All of the flight deck computers can be controlled from this compartment overriding cockpit commands and turning off the locator transponders". I work on 737NG, A320 Family and Dash8 Q400. The one thing all these aircraft have in common. If a computer is in use by the aircraft, then you cannot access maintenance modes or any mode come to that. To gain access to a "black box" (I am not referring to the FDR or CVR) you generally have to set cockpit switches in set positions before the computer will allow any form of access. Not only that but they all only have basic push button, press to test functions. Some my have a screen where you can go deeper, Boeing have a standard key pad on their aircraft but this is only on a small number. These consist of 4 buttons, an LED display. You can only select menus to press top test and transponder computers, again press to test. Reprogramming in flight is a Hollywood fantasy. Also you cannot turn off anything as all black boy functions are hard wired into the aircraft power systems and controlled from the cockpit. The only way to turn off a computer is to remove it and to do that without very serious consequences takes a bit more than a little homework.
Matt
"A bit of a pickle" - British translation: A catastrophically bad situation with potentially fatal consequences.
PETA

People Eating Tasty Animals.
B1 (Cat C) licenced engineer, Boeing 737NG 600/700/800/900 Airbus A318/19/20/21 and Dash8 Q-400
1. Captain, if the problem is not entered into the technical logbook.........then the aircraft does not have a problem.
2. And, if you have time to write the fault on a napkin and attach to it to the yoke.........you have time to write it in the tech log....see point 1.