It has been so popular that other airlines have copied the idea. America Airlines offers "Main Cabin Extra" and Delta Air Lines has "Economy Comfort."
Now a major airline may be considering another breakthrough idea: "Economy Minus," a seat that offers less legroom at a discount price.
Before you scoff, consider that a new survey found that 42% of airline travelers said they would be very likely or somewhat likely to book a seat with less legroom if it means getting a cheap fare.
The importance of price is highlighted by another finding from the survey: 97% of fliers say it is either very important or somewhat important when booking a flight, according to research company YouGov, which polled 1,145 adults.
The idea of a new "Economy Minus" seat surfaced last month when the news site Runway Girl Network reported that a major carrier was considering adopting a seat with a pitch of 30 inches or less. Pitch is the distance between the back of your seat and the back of the seat in front of you. The site reported that the tip came from an airline representative who asked that the airline not to be named.
The U.S. Department of Transportation does not impose seat size standards. Instead, federal regulators require that airlines offer enough space so passengers can evacuate in 90 seconds or less with half of the exits blocked.
Passenger rights activists say the "Economy Minus" idea is part of an airline industry trend to squeeze passengers for more profits.
Paul Hudson, president of the 50,000-member Flyersrights.org, said his group is pushing federal regulators to adopt airline seat standards of at least 18 inches wide, with a pitch of at least 35 inches. The tightest economy seats now offered on Spirit Airlines are 17.75 inches wide with a pitch of 28 inches.
"It's a real problem," Hudson said of the airline seating trend. "It has gone beyond being a comfort issue to being a safety issue."
United may have created "Economy Plus," but a spokesman said it is not the airline that is thinking about launching "Economy Minus."