Americans, take heart (and take a seat) - all those years of squeezing one's bottom into the torture device also known as an airplane seat is not your fault:
In 1962, the U.S. government measured the width of the American backside in the seated position. It averaged 14 inches for men and 14.4 inches for women. Forty years later, an Air Force study directed by Robinette showed male and female butts had blown up on average to more than 15 inches.
"The seat is a revenue generator," Luedeke says. "Normally if you look at a 737 or A320 there are three seats on each side. If you wanted maximum comfort you could do two on each side -- and make the seats a lot wider. But with the reduced head count the operational costs don't work out."
But the American rear end isn't really the important statistic here, Robinette says.
Nor are the male hips, which the industry mistakenly used to determine seat width sometime around the 1960s, she says."It's the wrong dimension. The widest part of your body is your shoulders and arms. And that's much, much bigger than your hips. Several inches wider." Furthermore, she says, women actually have larger hip width on average than men.
The industry used the male hip as a seat measuring stick "thinking that it would accommodate the women too, but in fact they don't accommodate the larger women."
The result: Airline seats are approximately 5 inches too narrow, she says. And that's for passengers in the 1960s, let alone the supersized U.S. travelers of today.
Thom Patterson of CNN's The Traveler's Psyche has the story: Link