I am reluctant to post on this topic (being very old and retired!) but I have a reasonable amount of flying experience (civil & military) and have flown in that part of the world. My knowledge of the 777 is nil but I have a reasonable idea of what is available on equivalent modern airliners. No idea of the "revised" flight path of MH370 (like anyone else!) but it would appear possible that it did not impact (if it did) in the sea, but may have continued on a track that put it over some fairly inhospitable land terrain (Jungle/mountain). This would certainly pose more problems in the search. Just a thought! (As mine are with the NOK!)