If it was pilot suicide he's not going to go to the trouble of turning off tracking equipment. It's also unlikely a pilot is going to hijack his own aircraft for political or economical means.
Question is how on earth can a plane these days, post 9/11, be hijacked? If it was hijacked by someone other than the pilots the passengers are going smash the door in. Maybe that's what's happened and it crashed.
In any case, whoever hijacked the plane, it's unlikely it hasn't crashed. Hope I'm so wrong on that one. Imagine the relief and jubilation felt by all if everyone was found safe.
The whole thing is just bizarre. Dumbfounded by the lack of security and the ability to so easily knock out tracking equipment. If you saw a Hollywood movie last night with the exact same storyline you'd discount it as a pure fantasy.