The number of Boeing 757s airplanes inspected for loose seats grew to nearly 50 Tuesday, as American Airlines zeroed in on the cause of loose seats on three flights in five days, airline officials said.
Though the airline planned to inspect only eight planes for loose seats, that changed Tuesday when American said maintenance crews would inspect 47 planes out of "an abundance of caution," said Andrea Huguely, an airline spokeswoman.
Work crews found "the root cause is a saddle clamp improperly installed," she said. The clamps were used on 47 of the airline's 102 Boeing 757s.
Huguely confirmed seats came loose on a flight between Vail, Colo., and Dallas-Fort Worth Friday. Similar incidents occurred on Saturday, when American Flight 685 from Boston to Miami diverted to Kennedy Airport. On Monday, Flight 443 from Kennedy to Miami returned to Kennedy without incident after loose seats were found.
Arlene Salac, an FAA spokeswoman in New York, said both aircraft involved in the Monday and Saturday incidents had recently undergone maintenance during which the seats were removed and reinstalled.
The Federal Aviation Administration is investigating the incidents.
Huguely said the loose seats on planes, all Boeing 757s, were not the result of sabotage by workers. The airline's union employees are unhappy about pending layoffs, and cuts in pay and benefits that American has imposed since filing for bankruptcy protection in November.
American has accused some pilots of conducting an illegal work slowdown that has caused a jump in canceled and delayed flights.
An initial review by American indicated that there could be a problem with the way the seats fit into tracks on the floor of the Boeing 757, but technical teams from the airline "are looking at everything," Huguely said.
In both cases, American employees were the last to touch the seats, which were removed and reinstalled during maintenance, Huguely said.
A Timco spokesman declined to comment beyond saying that the company is still investigating.