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  • #16
    That's the same tradeoff with things like railways. A properly run railway is extremely safe, in terms of injuries and deaths per passenger mile. When an injurious accident *does* happen, however, it tends to hurt and/or kill a large number of people at once - simply because you have several hundred people packed into a collection of vehicles weighing hundreds of tons and travelling at high speed in immediate proximity to other such collections of vehicles travelling at equally high speed. And if a systemic problem has been lurking in that particular railway for a while (eg. in Britain about a decade ago, there was a huge backlog of track maintenance, and the Japanese' obsession with punctuality has also bitten them a few times), there can be a spate of such accidents.

    The trick of course is that now it's not individual drivers' errors which have caused the accident, but a system which somebody has overall responsibility for. Which means that the system as a whole can be changed to make it work better - in the case of railways, by updating the rulebook and changing management practices. The initial response can be simple and over-cautious (double-man the cab) until a more sophisticated and efficient solution is found (fit automatic train protection systems, which force-stop the train if it passes a red signal, or if it is going too fast to be able to stop at the signal, or is going too fast at entry to a sharp curve).

    Accordingly, railways are accepted as safe in most civilised parts of the world. Britain's railways are currently regarded as the safest method of transport in Europe, and Japan's possibly the safest in the world (which is remarkable given the higher rate of natural disasters there) - apparently not one single passenger has been killed on the Shinkansen network, ever. So in fact, the actuaries *do* have something to refer to.

    Incidentally, an aircraft fitted with EFI typically has a greater safety margin than one without, simply because it may be able to fly higher (although most modern piston-engined aircraft are also limited by lack of cabin pressurisation - ie. you can't safely fly over 12000 feet). This gives more time to look for a place to land, and even in mountainous country you can often (though not always) glide down the mountain to more level ground. Fixed-wing aircraft don't just fall out of the sky when they lose power, they can still glide for a while - some airliners can do so for half an hour, starting at cruise altitude! Things are much more dicey with a helicopter though, which is why most have two engines attached to one rotor.
    Last edited by Chromatix; 10-08-2012, 01:01 PM.

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