An advisory committee will hear testimony today from expert witnesses, including the Federal Aviation Administration Civil Aerospace Medical Institute, the Centers for Disease Control, and the inventor of the Knee Defender, a gadget designed to prevent airline seats from reclining.
At issue is the move by many carriers toward higher density aircraft. Airlines around the world, including American Airlines, KLM, Air France and Emirates among others, are expanding their high-cost, high-margin first and business class sections, but they don't want to cut back on the number of paying passengers in economy. So they're installing lighter, narrower seats and squeezing rows closer together.
That is helping push profits skyward, to record levels in the case of Air Canada.
Same space, more seats
According to the Wall Street Journal, in 2010, about 15 per cent of the largest version of the Boeing 777 were delivered with nine seats per row.
In 2012, the paper says, more than 70 per cent of 777s came with 10 seats per row.
Seat width is down from about 47 centimetres in the 1990s to as narrow as 42 centimetres on some flights now.
But it's legroom that has become even more cramped.
The seat pitch, or the distance between your seat and the seat in front of you, on Air Canada flights in economy on Boeing's 767-300ER is as much as 86 centimetres.
On Rouge, Air Canada's discount leisure brand, seat pitch on the same plane (excluding Rouge Plus) is 76 centimetres.
"Like our main Canadian competitors, Air Canada has reconfigured its aircraft to add more seats in order to remain competitive," says spokesman Peter Fitzpatrick.
Fitzpatrick says passengers have the option to purchase "preferred seats" throughout the aircraft that offer more legroom and Air Canada is also introducing "premium economy," with pitch of 97 centimetres in its widebody fleet.
On its Rouge carrier, Fitzpatrick says, "seating is designed to match that available on competing leisure airlines" and has remained the same size and pitch since the airline's launch.
Standard seat pitch on Westjet's Boeing 737s is 79 centimetres to 84 centimetres.
Long legs? You're out of luck
Diminishing legroom can be annoying for average-sized people. If you're above average though, it can be torturous.
"I had to sit almost in the fetal position," says Dave Rasmussen, who is seven feet three inches tall and suffers from a pulmonary condition that makes it hard to breathe when sitting hunched over.
"I couldn't put my feet down on the floor. I just put a pillow between my knees and the seat ahead and I kind of sat there in the fetal position for the hour flight, or whatever it was."
Rasmussen, who works in information technology for the University of Wisconsin, says he "doesn't have a basketball player's salary" and can't afford to go business class.
Airline employees used to put him in the exit row, but now anyone can buy those seats for an extra fee. With regular seats getting smaller and smaller, Rasmussen says it has gotten tougher for him to travel.
"I think humanity has sort of lost touch with what's good for people as opposed to profits for executives. I believe that transportation should be something of a utility. It should accommodate the people," Rasmussen says.
Without legislation, some passengers are guarding their shrinking legroom any way they can.
"Nobody wants to buy [my] product. They buy it because it's the least bad alternative to the situation they're in," says Ira Goldman, inventor of the Knee Defender.
His device, which attaches to an airline seat's tray table and prevents the seat in front from reclining, made international news last summer when a man using it had pop tossed in his face by another irate passenger.
Goldman is scheduled to testify at the US DOT committee hearing. He says that without some sort of regulatory involvement, there's nothing to stop airline seats from getting even smaller.
"They have no financial downside and every financial upside to cram us in there," Goldman tells CBC news.
Consider the head of discount carrier Ryanair once famously suggested selling standing-only tickets as a way to cut costs.
A recent study suggested a standing cabin would increase the passenger capacity on a Boeing 737 by 21 per cent, while lowering fares by as much as 44 per cent.
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