I see from Wikipedia that Malaysia Airlines 370 is still considered missing. I also see from Wikipedia that a thousand conspiracy theories have already sprung up to account for that. Apparently some people do not deal well with loose ends, or just aren't aware that there are quite a number of aircraft that have crashed and were never found.

I realize that it is de regueur to blame terrorists for everything up to and including the late night pizza joint getting your toppings wrong, but there are several previous losses that fit the same profile as MH370 -- that is, an aircraft that flies silently on in an unexpected direction long after all radio contact with the humans on board have been lost, and then stops pinging after a length of time consistent with running out of fuel and nosing into terrain. (Well, in this case, ocean.) All the ones I know of have been decompression incidents. If the cabin loses pressure in an explosive fashion, generally the oxygen masks drop down from the ceiling and everyone knows what's going on, but if the leak is slower, it's entirely possible for the crew to have several minutes of disorientation in which to take some scrambled, semi-random action to try to fix the problem, before everyone on board dies of hypoxia, and the aircraft streaks onward unattended.

Probably the most famous one was Helios Airways 522, mainly because that one took place right off the coast of the Mediterranean, in controlled airspace, and ultimately crashed on land. The flight crew mistook a cabin pressure warning for a different alarm (that couldn't have sounded in flight, and was therefore doubly confusing) and dicked around trying to fix it as they ascended to cruising altitude, where the low oxygen content of the air is incompatible with life. It was first noticed that the problem was deadly rather than annoying when the flight passed into Athens ATC airspace without talking to the controller; the Greeks, rather concerned about a large and uncommunicative jet wandering over their country, sent up some F-16s to give them a wing-waggle, and the fighter pilots reported that everyone visible through the cockpit windows was slumped unconscious or dead over the console. A flight attendant with a license to fly much, much smaller airplanes gave a good go at flying the Boeing with an oxygen mask on, but ultimately lost to hypoxia and gravity.

If anyone ever worries about the autopilot on these things, incidentally, don't. Helios 522 made it all the way from Cyprus to Greece and slotted itself quite happily into the standard holding pattern at the Athens airport without any human assistance whatsoever. The equipment type was a 737, which are bears of very little brain by current standards. I wouldn't be surprised if a newer Boeing or Airbus could land itself the same way, at an airport with sufficiently sophisticated nav beacons. The main effect the flight attendant's attempts had, intentionally or not, was to make sure the thing went nose-first into a hill instead of a chunk of city.

Lesser-known but entirely over land was the 1999 crash of a chartered Learjet in South Dakota. This was somewhat unexpected, as it was supposed to be flying from Orlando to Dallas. The cabin depressurized before they could make a left turn over the Florida panhandle, and the jet kept going over the Midwest until it ran out of fuel. The flight headed northeastish into largely uncontrolled airspace -- there is a lot of uncontrolled airspace in the US, believe it or not, although virtually all of it is painted on military radar somewhere -- and was intercepted for visual inspection several times by USAF and National Guard jets, all of which reported that the plane looked fine on the outside but was dark and showed no signs of life on the inside. Nobody seemed to know what what to do about this, so they mainly kept an eye on it until it ran out of fuel, the resulting loss of thrust confused the autopilot, and the craft rolled over and went down in a cornfield.

(The Learjet is also notable because on its way to South Dakota, the plane made it to almost 49,000 feet, which is quite a bit above the official operational ceiling of its engines. Also probably above the official operational ceiling of its fuselage, which may have lost pressure before getting there, if it hadn't been leaking before.)

The conspiracy theories about MH370 seem largely to be based on the fact that it headed in an unexpected direction before vanishing, to which I say: You try not breathing for two or three minutes and see how well you navigate. The delay in figuring out which way it turned was mainly due to the fact that that region is full of small countries with limited defense budgets who are all deeply suspicious of one another, and united mainly by the fact that they all have historical reason to hate the British. I am also not particularly impressed by the Malaysian minister of whatzit who apparently decided the best way to deal with this was to blurt out whatever came into his head whenever the media approached him. China was strangely cooperative, but I'd think they would be if they really weren't responsible for the loss of the aircraft -- they've shot at/threatened to shoot at stuff in their territory before, and were not shy about saying so.

There are quite a lot of very large objects that have headed off into or over the ocean and never been heard from again. The list of aerial disappearances on Wikipedia is staggering. It took them years to find most of the chunks of Air France 447, and it went down pretty much in one piece, not far from where they started looking.

Comments

  1. Nice analysis - and probably correct.

    Lack of oxygen is fatal, captain's arrogance ditto. Many planes have flown into a hill because the captain was such a donkey he (usually he?) was such a demi-god he would not listen to the second-in-command - or the second-in-command would not talk to him.

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