[quote=CDMA ENG]On a serious note though I am surprised after the Air France incident that the motors’ computers are tied to a independent GPS signal as well. I am not sure how important positional information actually is but if you are trying to account for strange anomalies to the motors I would think basic information like altitude, speed, and heading from independent sources instead of relying on a “central” computer whose own inputs may be in question.

I know that the motors are all monitored in real time though an engineers eyes are not actually looking at the motor unless it is running out of spec but it can serve as another source of information.

I also suspect that if the communication channel is not able to be switched off like the transponder is then the engineers have looked at the motor’s performance characteristics and the authorities have drawn their conclusion about the flight from that.

CE[/quote]Umm can’t go into too much detail else I might describe basics to building a GPS guided missile. GPS only provides position and time (if you have 4 sats) Proper feedback loops do account for motor problems. The biggest problems are when your sensor inputs go bad. They don’t always tell you that they have gone bad. You have to deduce it from the divergence in ‘solutions’.

PS: GPS itself can be spoofed, so you don’t want a direct connection between control surfaces and GPS.