September 19, 2012

# They don’t reverse into mountains

That’s how I first heard the theory that it’s safer to sit at the back of a plane than at the front. It turns out there’s something to it: back in 2007, Popular Mechanics magazine looked at data on all the US plane crash fatalities over 35 years and found a roughly 40% higher risk of death in front of the wing.

Stuff is now reporting on a British TV stunt, where a plane full of crash-test dummies was deliberately crashed in the Sonoran Desert.  The test found that the front of the plane experienced higher accelerations, so you would be better off near the back. It also found that the brace position helped.  This, of course, applies to only one form of plane crash — the ‘controlled flight into terrain’, and only to a subset of those.  In some crashes no-one dies; in others everyone dies.

The conclusion that economy class is safer in general is much more dubious.  It can’t be much safer, since the chance of dying in a ‘fatal air incident’ is very, very, very small wherever you sit (Wikipedia claims about 1 per 10 million journeys). Crashes are only a subset of fatal incidents,  and the benefit of sitting near the back must be substantially smaller even than this. As a comparison, on an 8+ hour flight, the chance of pulmonary embolism is about 16 times higher than the chance of dying in a fatal air incident, and nearly 50 times high for a 12+ hour flight, so a relatively small reduction in risk in first class would outweigh any crash benefit.

Thomas Lumley (@tslumley) is Professor of Biostatistics at the University of Auckland. His research interests include semiparametric models, survey sampling, statistical computing, foundations of statistics, and whatever methodological problems his medical collaborators come up with. He also blogs at Biased and Inefficient See all posts by Thomas Lumley »

• Mark Runge

Does the 40% higher risk chance take into account that there are fewer seats in front of the wing for most planes? Just an observation that most planes, even when economy only, include fewer seats in front of the wing. So the difference may be driven error due to difference in by sample size between the “front” and “rear” populations?

• Thomas Lumley

Yes, it does. The Popular Mechanics article says:

Where detailed seating charts were available, we also calculated survival rates for various parts of the passenger cabin. Again, the trend was clear: The rear cabin (seats located behind the trailing edge of the wing) had the highest average survival rate at 69 percent. The overwing section had a 56 percent survival rate, as did the coach section ahead of the wing. First/business-class sections (or in all-coach planes, the front 15 percent) had an average survival rate of just 49 percent.