well considering i wouldnt go after an islamic countries aircraft if i was islamic,it wouldnt help my cause,plus a modern a/c like the 777-200er going down without a trace even if it hit the ocean there would have to b a breakup surely.mid air explosion or breakup of the a/c i think i would be to busy screaming to look for a signal on my phone ,which would be turned off anyway,full system meltdown possible i suppose i certainly do not hav the knowledge to answer that 1 maybe the users on this forum could giv us an indication on the likelihood?.explosives on board again those who work in the industry could answer how stringent would the security be to slip explosives on board especially in malaysia unless there was a diplomatic bag taken on board or would this still be searched anyway.hijacking could they get into the cockpit"open up or we kill the little girl in the aisle seat"possible i suppose ,but then where to and wouldnt we have heard by now.or mayb they turned back and went down in mountainous area.also even if decompression, wouldnt aircraft be on autopilot and still flying etc ? so it is very strange for this to happen