Clee mentions the possibility of a "cellphone disrupter" used by the military as a possible cause of the crash.
I am a ex grenadier guardsman and we used these devices when performing changing of the guard. if you have ever watched this event, when marching from wellington barracks to Buckingham palace you might notice one of the guys wearing a big box on his back, with a cover to match the tunic, well thats what they are. they were originally brought in to combat the threat of the IRA detonating roadside bombs when the guard change marched between the barracks and the palace, and at their most vulnerable. Anyone remember the horse guards killed in the same manner near hyde park some years ago?.
I do recall at the time (and this is some years ago!!) that they would play havoc with some car centeral locking systems and car alarms to our amusement!!, but these devices have come a long way in terms of technology in the last 15 years. They do have limited range and certainley dont have the capability to bring down a aircraft.