Yes i was thinking that, probably is going to be a big problem, if the receiver fails, the servos will be freeze and airplane BOOM!!!.
I wish the arduino developers program a time out function: pulsein(Pin, HIGH, timeOut); thats would be pretty cool. Any ideas???
But think again... if the receiver fail, with arduino or not, it will crash... is the same. By the way, ill use TWO arduinos, one for read sensors, precess the data, send information by UArts to ground, and this data (few bytes) will be sended to arduino 2 by i2C, arduino 2 only read PPM signals, and control servos.. (Automatic Pilot).
Is going to be DUAL CORE ;D I made some test and looks goods.
The only real deal is the kalman filters, but yesterday i figure almost everthing out (12 am until 6 am, that was my new year).