JACKSON, Wyo. — Aviation investigators are looking into two braking systems on an American Airlines plane that ran off a runway while landing at the Jackson Hole Airport.
A Boeing 757 carrying 181 passengers and crew came to a stop about 350 feet beyond the runway overrun area on Dec. 29. No one was hurt and the plane wasn't damaged.
The plane had taken off from Chicago.
The National Transportation Safety Board said this month its investigators discovered a component was missing from a cockpit mechanism that controls the speed brake, a set of wing flaps that rotate upward. The agency said it is investigating whether that affected the operation of the system.
Speed brakes reduce the lift provided by the wings after a plane touches down. That in turn puts more weight on the landing gear, which are being slowed as the flight crew applies the wheel brakes.
Speed brakes can also be deployed while a plane is still in the air and approaching an airport to help slow it down.
Investigators are also looking at how long it took plane's the thrust reversers to deploy, the NTSB said. Thrust reversers are mechanical devices that deflect the thrust of the engines to slow the plane after it is on the ground.
Investigators are reviewing the plane's cockpit voice recorder and flight data recorder, along with other records, the NTSB said.
They are also reviewing video from airport security cameras and video of the landing taken by a passenger.
The agency hasn't said when it would release its findings, but investigations typically take several months.