Air crash survival, land or sea better?

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I was having a discussion with a friend about whether you were less
likely to live if you crashed in the sea over crashing on land? Does
anyone have any statistics on this question?

-- Anneliese Godfrey, August 14, 2005


One statistic I have seen is that occupants survive a light plane ditching and subsequent paddling/rafting around 85 percent of the time. These data include ditching in severe conditions such as on North Atlantic ferry flights so possibly ditching in calm warm water would be even safer. I think the fatality rate for crashes on land is slightly lower. So it is better to crash on land.

-- Philip Greenspun, August 25, 2005

As a light aircraft pilot, I can try to answer a more specific question: if your aircraft has a total engine failure, are you more likely to survive over land or sea? And the answer to this is that, generally, you are much more likely to survive over land.

If you suffer a total engine failure, your plane becomes a great big glider. Over land, you would select a field beneath you to land in, set the aircraft for the correct gliding speed, and carry out what is not enormously dissimilar from an ordinary landing. This is the sort of thing that is practiced a lot during training, and most pilots would be able, most of the time, to carry out such a landing without serious damage to the plane or occupants.

Over the sea, such a forced landing is called a "ditching", and you do pretty much the same thing, and the chance of survival up till now is broadly similar to that over land. The problem is that, unlike a forced landing in a field, after which you can sit down and relax with a nice cup of tea, after a forced landing in the sea, your troubles are only just starting. In a light aircraft, you have a couple of minutes to get out before the aircraft sinks, and this is not necessarily easy as the pressure from the water will tend to make opening the doors tricky. Once you are out, although legally you will have a lifejacket with you and so presumably won't drown, you have to get yourself rescued before hypothermia sets in: even in the middle of summer, survival times without a liferaft in the open seas are typically just a few hours, and getting a search and rescue helicopter to pick you up can take longer than that, even if S&R already know exactly where you are, which they are highly unlikely to.

While I don't have numbers to hand, you will find if you look at light aircraft statistics that engine failures over sea are many times more likely to result in fatalities than engine failures over land. Indeed, many pilots will not fly over the sea on a single-engine aircraft unless they can remain within gliding distance of land.

I hope this answers your question.

-- Adrian Cable, August 24, 2005