National Transportation Safety Board - Docket And Docket Items: http://dms.ntsb.gov/pubdms
National Transportation Safety Board - Aviation Incident Data Summary: http://app.ntsb.gov/pdf
NTSB Identification: DCA11IA015
Scheduled 14 CFR Part 121: Air Carrier operation of AMERICAN AIRLINES INC
Incident occurred Wednesday, December 29, 2010 in Jackson Hole, WY
Probable Cause Approval Date: 07/02/2012
Aircraft: BOEING 757-223, registration: N668AA
Injuries: 185 Uninjured.
NTSB investigators used data provided by various sources and may not have traveled in support of this investigation to prepare this aircraft incident report.
The National Transportation Safety Board’s full report is available at http://www.ntsb.gov. The Aircraft Accident Report number is NTSB/AAR-12/01.
On December 29, 2010, about 1138 mountain standard time, American Airlines flight 2253, a Boeing 757-200, N668AA, ran off the departure end of runway 19 after landing at Jackson Hole Airport (JAC), Jackson Hole, Wyoming. The airplane came to rest about 730 feet past the departure end of the runway in deep snow. The 179 passengers, 2 pilots, and 4 flight attendants on board were not injured, and the airplane sustained minor damage. The airplane was registered to and operated by American Airlines as a scheduled domestic flight under the provisions of 14 Code of Federal Regulations (CFR) Part 121. Instrument meteorological conditions in light snow prevailed at JAC at the time of the landing, and the flight operated on an instrument flight rules flight plan. The flight originated from Chicago O’Hare International Airport (ORD), Chicago, Illinois, about 0941 central standard time.
The National Transportation Safety Board determines the probable cause(s) of this incident as follows:
a manufacturing defect in a clutch mechanism that prevented the speedbrakes from automatically deploying after touchdown, and the captain’s failure to monitor and extend the speedbrakes manually. Also causal was the failure of the thrust reversers to deploy when initially commanded. Contributing to the incident was the captain’s failure to confirm speedbrake extension before announcing their deployment, and his distraction caused by the thrust reversers’ failure to initially deploy after landing.
WASHINGTON — Just before an American Airlines plane ran off a Wyoming runway last December, the pilots struggled to engage the brakes and thrust reversers that help slow speed, according to documents released Friday.
None of the 181 people aboard Flight 2253 from Chicago was injured in the incident at the Jackson Hole airport, but the material made public by the National Transportation Safety Board raises questions about the Boeing 757-200’s braking system and the pilots’ actions.
The pilots had anticipated a rough landing as they approached the airport, according to a cockpit voice recorder transcript and other documents.
Light snow was falling and conditions were icy. On top of that, the airport’s runway is short. The pilot of a smaller plane that had just landed told air traffic controllers that the first two-thirds of the runway were fine, but braking was “poor” on the final third.
A few minutes before landing, the American captain told passengers: “We don’t try and make a smooth landing here at Jackson Hole. We just put the aircraft on the runway very quickly and firmly and go into full reverse and then use a heavy amount of braking (to) make sure we stop in the first part of the runway. So just be aware of that that’s normal procedure for a mountain airport.”
As the plane touched down, the pilots struggled several times to engage the thrust. “No reverse ... I can’t get it,” said the first officer, who was at the controls. They finally succeeded, but by the plane was nearly out of runway.
The captain’s call for the brakes to be used was followed by sounds of physical exertion, mechanical clicks and thumps. “All right, I got max brake,” he said.
But four seconds later the first officer swore, and then said: “I don’t know what the (expletive deleted) is wrong. ... We’re screwed.”
The plane is then heard thundering off the runway. It came to rest in deep snow 730 feet past the end of the runway.
“Well ... end of our career,” the captain said.
But the first officer insisted, “It’s not the end. We did everything right. We didn’t get the thrust reversers.”
The pilots did acknowledge in interviews with investigators that they didn’t try to manually engage the plane’s speed brakes — essentially wing panels that pop up — as American’s procedures require under the circumstances.
The pilots have successfully completed “corrective action” under an American program that doesn’t penalize pilots who disclose errors, the airline said in a statement.
The safety board is continuing to investigate the Dec. 29 incident. The transcript was released along with more than 300 pages of evidence gathered by investigators, who will try to now figure out what caused to the overrun and make safety recommendations.
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