IF I FELL OUT OF A COMMERCIAL AIRCRAFT, WOULD I BE DEAD BEFORE I HIT THE GROUND?

A commercial jetliner cruises at around 830km/h at an altitude of 10,000m. Quite apart from the fact that the doors are locked automatically while in flight, the pressure differential at that altitude is more than five tonnes per square metre. Aeroplane doors open inwards so it would be like trying to open the door with an elephant sitting on it.

All of this means that in order to fall out in the first place, something very bad must have happened to the plane itself, such as an explosion or catastrophic structural failure, which is already likely to cause serious injury. Assuming you survive that, and don’t hit the wings or tail on your way out, you will find yourself in air at less than a quarter of the normal sea-level pressure, and temperatures of -48°C.

The US Federal Aviation Authority gives a “time of useful consciousness” of just 30 seconds at this altitude. This is the period where you can still react rationally to your surroundings before the lack of oxygen overcomes you. Beyond this point, you will be groggy and disorientated and will soon pass out, but you won’t asphyxiate.

Studies in the 1960s found that chimpanzees could survive up to three and a half minutes in near vacuum without any long-term effects. Of course, you are also falling this whole time at about 200km/h, so every minute brings you 3,300m closer to the ground. At most, this gives you three minutes to endure atmospheric conditions that are getting milder the further you fall.

After that, you have much bigger problems to worry about. Only one person has ever survived a fall from an aeroplane at that altitude: flight attendant Vesna Vulović who was on JAT Flight 367 in 1972 when it was blown up at 10,160m by a terrorist bomb. But she was trapped inside the damaged fuselage, which partially cushioned her impact.