As I'm sure you've heard by now, a Boeing 777-200 operated by Malaysian Airlines has disappeared. I am writing this about a week after this plane vanished and am simply amazed at some of the speculation regarding the events leading up to the disappearance of this aircraft. I have read theories about how the plane could have been hijacked and flown to Africa, China, or the Middle East to be used as a weapon at a later date. Others suggest that it was flown so close to a different Boeing 777 that its radar image merged with the other airliner allowing it to remain hidden until it was in an area of limited radar coverage where it was free to move about hidden from prying eyes. The current list of theories is as long as the list of "experts" that have displayed their level of ignorance as much as their expertise.
What do we know?
The only thing that we know for sure is that the airplane and all on board are missing. Aircraft telemetry systems shut down for some unknown reason and the aircraft performed a few maneuvers before vanishing.
The hijacking theory suggests that the hijackers turned off the transponders on the airplane. This is plausible but would these supposed hijackers have enough knowledge of the systems to disable all of the systems that report automatically? It seems that the only system that can't be disabled from the flight deck is the engine monitoring systems that report to Rolls Royce in England. This makes it possible but, in my opinion, unlikely that the systems were turned off in an attempt to hide the airplane.
What do I think happened?
I am no expert but since everybody else is offering up their opinion, I will too.
I think that two scenarios are possible, an on board fire or a shoot down.
The on board fire is the most likely in my opinion and could have been growing in the avionics bay or in between the hull and interior panels for some time before becoming and issue. In 1998,
Swissair Flight 111 was lost after take off from JFK due to a fire that started in a wiring bundle that powered the in-flight entertainment system. The fire spread with little notice, caused electronics failures, and was discovered too late for the crew to save their aircraft.
Damage to the aircraft's electronics along with a possible hull breech due to the fire could have caused two things to happen that would explain the altered flight path. Let us assume for a second that the pilots were flying along fat, dumb, and happy. Then, equipment starts to fail. The radios and navigation equipment fails, smoke starts to fill the cabin and then a rapid decompression incapacitates the crew and all of the passengers.
What would happen now?
Without human intervention, the airplane would follow whatever was programmed in to the autopilot. If the autopilot had failed, the plane would be at the mercy of the winds. A plane that is set up to fly straight and level with continue to fly straight and level until it is upset be some force. The stability of modern airplanes will return the plane to straight and level flight eventually but how long that takes depends on many variables. What the plane does while it is returning to its original state depends on how it was upset and how much force was behind that upset. It could easily climb, descend or turn after being bumped by turbulence, being hit by a sudden and strong shift in the winds, etc. Eventually the airplane would run out of fuel and crash. Even without engines, this airplane could have glided hundreds of miles depending on its altitude and possibly crashing in some lonely part of the ocean, African desert or thick jungle forest without anybody noticing.
This is just my own theory and I will post updates as things develop but I will try to filter fact from fiction as best as I can. One thing is for sure, there are families out there that are missing their loved ones and they would like to have some answers that may never come.
Boeing offers a 
