My initial reaction to this was to ask something along the lines of "you're kidding, right?". I thought that, in response to questions I've been asked on the subject, and as a public service, I'd take this opportunity to refute the statement, as follows:
- Of the airliner accidents that occur every year (not a very big number, and it's dropping further), most of them occur too close to the ground for a parachute to be of any use (i.e. accidents on take-off or landing).
- Of the accidents that don't occur at low-level (for example, the highly unlikely event of a mid-air collision), there isn't likely to be time to bail-out, and the aircraft (or what remains of it) would most probably be in a spin or some other highly unstable trajectory, with the forces aboard precluding bail-out at all. What are the odds of an incident where a bail-out was the only option with any chance of survival, but the aircraft conveniently was able to hold itself in a steady attitude for several minutes? Somewhat low, I suspect.
- Ignoring these issues for a moment, let us assume a cruising altitude of, say, 30,000ft. At this level, the useful time of consciousness in the event of a loss of oxygen pressure (caused by, for example, opening a door) is roughly 15 seconds. It is therefore unlikely that a parachutist without oxygen supplies would survive a jump, or even make it out of the door, unless he or she were at the front of the queue. Even then, you're going to get people blocking the exits because they don't want to jump...
- While on the subject, it's bloody cold at 30,000ft...
- How long would it take to evacuate an airliner like this? You couldn't use the forward exits, as there's the small problem of being sucked into the engines that are inconveniently mounted under the wings.
- I've had no parachute training, but I'm given to understand that there's rather more to it than jumping out and pulling the cord. You're asking someone who's never seen a parachute before to work out how to put it on securely and correctly, work out how to deploy the chute whilst hurtling towards the ground from a great height and whilst suffering from oxygen-deprivation and hypothermia, and then make a landing on whatever surface might happen to be present without breaking a leg or two...good game, good game...
- Let's assume (just for the sake of an arguement) that all of this gets worked out and that everyone makes it out safely. Now what? On a flight from London to New York, for example, quite a substantial amount of time is spent over the North Atlantic, which is, shall we say, a bit chilly. Without survival gear (wetsuit, liferaft, etc.) you're unlikely to last for very long floating in such water, even if young, fit and healthy. Sure, you could drop liferafts from the aircraft at the same time, but the passengers are going to be spread over several miles of sea - how are they going to meet up with each other? And how long could it take for help to arrive? At this point, you may wish to recall the end of the Titanic movie...
- To quote from The Simpsons:"Won't somebody PLEASE think of the children!!!"
- Then there's the cost: the parachutes themselves cost money, and they have to be repacked regularly; they also weigh a fair bit, and in the flying business, any extra weight equals extra fuel needed, equals increased costs. Hands up anyone willing to pay double the usual airfare in order to have a parachute that you're almost certainly not going to need, and which wouldn't help you anyway?
Flying is very safe; it is, in fact, by some considerable margin safer to fly than it is to cross the road. It is said that if you were to fly every day, you'd be involved in a serious accident approximately once every 13,000 years. I quite like those odds, so I'll leave the parachute behind and have a bigger baggage allowance, please...
[the above was originally published by me as a Facebook note in September 2008]
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