Whoops!

Fun for Southwest Airlines passengers during a flight when there was a loud bang then a hole opened up in the roof of the aircraft. The FBI told people not to worry as "terrorism was not suspected, it appears to be a mechanical issue". Oh goody- we are not being bombed, the aeroplane is just falling apart under us!

According to the airline, this is not a major problem (!) they have about a hundred aeroplanes of this type (Boeing 737) and only one other has suffered an incident like this before. This means that you have a 98% chance of flying in a safe aeroplane........And a 2% chance of the aeroplane disintegrating in mid air!

The investigation is not yet complete, but the most likely cause was metal fatigue. I looked up the physics on this, all metals are tested for tolerance (I.E. to work out the "shelf life" of the aeroplane and ensure it is taken out of commission long before it is likely to fall apart in mid air). The calculations involve a formula called "The Palmgren-Miner Linear Damage Rule", which is long, complicated, and involves what looks like a differential equation (I avoid anything that even looks like a differential equation on the grounds that, many years ago, I failed an interview for a scholarship to Dulwich College because I did not manage to resolve a differential equation that they set for me). The equation includes a constant that (and here I am quoting) "...is experimentally found to be between 0.7 and 2.2. Usually for design purposes, it is assumed to be 1." Or in other words "It could be anything between 0.7 and 2.2, but when we design aircrafts we guess an it being 1." And they wonder why the fucking things fall apart in mid air!!!!

From now on I don't think I'll go anywhere that is so far away that I cannot get there by bus.

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From the BBC report:

'The National Transportation Safety Board said an "in-flight fuselage rupture" led to the sudden descent and drop in cabin pressure. "We do not know the cause of the decompression" Federal Aviation Administration spokesman Ian Gregor said.'

Just a slight hint Ian: I don't know much about the physics of flying (I never got that scholarship, remember) but I would guess that the "cause of the decompression" probably has something to do with the sodding great hole that opened up in the roof!

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On a side note, it was reported that no passengers were hurt, but "a couple of people aboard nearly passed out while trying to put on oxygen masks." Putting on an oxygen mask simply involves holding the damn thing in front of your mouth. If you are still having problems doing that, perhaps you want to consider the possibility that you have not yet reached the stage in evolution where you are capable of being a passenger on an aeroplane!