would any passenger be able to initiate a text/voice call if anything other than something sudden were to happen (instantly incapacitating all crew and passengers)?

And if a large explosion occurred (enough to completely demolish the plane beyond small pieces), you'd think NSA or some spy agency would see/detect it? I mean really, NORAD isn't totally asleep at the switch here.

And is that the best Chinese satellites can do in terms of resolution? I'm sure they've got stuff as sharp as western nations (heck, they built half the crap in our surveillance satellites). But maybe they have older satellites patrol this area of the globe and use their top stuff to look at other areas (like S.Korea or something)

My money is on something sudden happened, since I'm sure any passenger with a communication device would attempt some contact if a long, drawn out problem happened (like smoke in the cabin, etc)