[RayChuang88]

If there is no communication from the pilot, then something catastrophic happened. That increases the chance a bomb on board the plane may have exploded and brought it down.

[djf]

I doubt it was a bomb. There are a million things that can go wrong with a plane that size.

Our guys (spook type guys) probably know already, but can’t say anything without compromising sources/techniques.

[CodeJockey]

This is true. No mayday signal would indicate a major catastrophe.

[dragnet2]

IMO, bomb unlikely, as the bad guys like spectacular events, with lots of gore and cameras around and they generally take credit for their handiwork rather quickly.

Could have been pilot error, airframe failure, engine/ mechanical....Who knows at this point..

I think they'll find debris soon enough..

[the OlLine Rebel]

No, look up Air France.

Things DO suddenly go wrong, including sleeping staff and silent communication systems.

[Cruz_West_Paul2016]

If there is no communication from the pilot, then something catastrophic happened. That increases the chance a bomb on board the plane may have exploded and brought it down.
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that seems to be the most likely scenario, either something blew in the plane/engine failure or in my recent reply,ground to air attack.