Originally Posted by 787FOCAL
How many of you pilots have used hand held GPS on the flight deck? (I know nobody will answer that)
GPS is a passive receiver, and the processing power required is very moderate, so it would not be a big source of RF radiation.
The reall reason they don't want you using and electrical devices during takeoff and approach is because they don't want them flying into people if a crash happens. How do you think a cell phone would feel at 100 mph?
If that were true, they would say "please make sure all hard objects are stowed securely", and not "please turn off all electronic devices".
I always found it curious that digital cameras do not seem to count as electronic devices, although they undoubtedly are.
I've never heard a flight attendant object to me using even a 1+ kg digital SLR camera during takeoff and landing.
fyi - Isn't there an airline in the EU that is installing a system that will allow people to make and receive cell calls in flight?
If so, this is going to limit the radiated RF power significantly, as the mobile phones will only transmit at minimum power, as opposed to near maximum power when trying to reach a repeater on the ground.
Originally Posted by fcom
A possible cause to the accident could have been a failure of the autothrust system if this was engaged at the time.
Not according to the AAIB initial report, knowing how the Autothrust systems works on the B777 aircraft.
All the system does is physically move the thrust levers, and the thrust control system then does the same things as if the levers had been moved manually. According to the initial report, the autothrust system moved the levers forward, without response from the engines, and some time later the flight crew moved the levers, with the same (i. e.: no) result.
Originally Posted by slink
The A340 accident was totally different.
(Referring to the Accident at Toulouse-Blagnac)
It was indeed, and as had been said in the appropriate thread, the load experienced by the hull in that case was totally unforseen by the designers, unlike the loads in this crash landing, which were expected.
A better comparison between the B777 and the A340-600, if we want to go there, is the very hard landing at Quito a few months ago. Although they "crashed" on the runway, sink rate was excessive (>1000ft/min, what BEA/Airbus in an Accident Information Telex called an "extremely hard touchdown") and the landing gear was damaged in such a way that the strut compression was no longer signalled and subsequently the thrust reversers were inhibited, causing an overrun. About the same sink rate caused the tail to fall off a DC9-80 at touchdown in a certification flight in the 80s.
My point? Nothing can be derived from this accident alone about the structural robustness of the B777 airframe compared to those of similarly-sized competitors' aircraft. This one was fine here, the Airbus was fine at Quito.