There are lots of uncomfortable things about air travel. There are long waits on the tarmac, milk-run flight schedules, luggage fees, lukewarm food that tastes like cardboard and bad in-flight movie selections. The list of grievances is endless. But now, FlyersRights, an advocacy group for air travellers, has submitted a petition to fix one particular airline gripe. The non-profit group has gathered more than 30-thousand signatures on a petition that urges the US Congress to set a legal minimum airplane seat size.

Kathleen Robinette (Kathleen Robinette)

The hexagon face-to-face design. (Zodiac Seats France)

"The seats were designed for a 95th percentile hip width or butt width...that means one out of every 20 people are wider," Kathleen Robinette tells As It Happens guest host Laura Lynch.Robinette is the head of the Department of Design, Housing and Merchandising at Oklahoma State University. She has advised the Air Force, NASA and the Federal Aviation Administration on airplane design.Robinette says design flaws may start with the hip width but are even more restrictive when extended to other parts of the body."The widest part of our bodies are across the shoulders and arms, that means it's more like 20 to 25 per cent that are wider than the seat," she explains."They weren't thinking," she adds. "When people think 'seat' they think what you sit on, they don't think it's got to accommodate your whole body."Robinette says the design is also based on financial incentives and the airlines' ability to maximize passenger capacity. If airlines offer more accommodating seats, they inevitably offer fewer seats, which means more expensive tickets to cover costs. The change would allow competing airlines to step in and undercut them."It perpetuates the problem," she explains.Consumers still make price a priority over comfort but Robinette says there are serious health concerns."If you can kind of turn sideways a little bit you can accommodate a longer distance but because the seat is too narrow you can't turn sideways either so you're kind of crammed in there like a sardine."The narrow seat width and legroom allow the passenger little "wiggle room". Robinette explains that this can eventually lead to "deep vein thrombosis which is basically the blood clot that forms, in this case, in your legs."While airlines encourage passengers to get out of their seats and stretch, Robinette says factors such as turbulence and seating location also limit mobility. Other airlines offer in-seat exercise instruction but again, Robinette explains, "you can't do those exercises in your seat if there's no room to move in your seat, so it's kind of nice in theory but in reality you can't do them."Since the 1970s, Robinette says there has been little change in the size or design of seats."The issue is the seats haven't changed much, we are getting bigger, especially in North America we are getting fatter."Robinette recommends that airlines extend the width to 21 inches, or 53 centimetres. That's approximately 10 centimetres wider than standard airline dimensions. She supports the FlyerRights petition but thinks it should also be mandatory for companies to provide the dimensions of seats to passengers."Kind of like food labels," she explains. "It enables the consumer to be an informed consumer."FlyersRights have forwarded their petition to the Federal Aviation Administration. Robinette appreciates the group's initiative but doubts the airlines will change. She explains, "unless they can have good evidence that it's a safety issue they will probably not pass a law."She confesses, "when I travel I usually upgrade to a more accommodating seat because to me, it's worth it."Perhaps FlyersRights should contact Zodiac Seats France . Earlier this summer, the aerospace company filed a patent to the World Intellectual Property Organization, proposing a new space-saving design for passenger airline seats. The unsual hexagon design saves space by having seats face each other.