Video: 757 Overrun Video Ignites Pilot Speculation
Video shot by a passenger aboard American Airlines Flight 2253 as it overran Runway 19 at Jackson Hole, Wednesday, shows unusual operation of the aircraft's systems, according to some pilots. The 6,300-foot runway sits at an elevation of 6,451 feet and the pilots landed in light snow at about 11:37 a.m. About seven inches of snow had fallen in the area since midnight, but the runway itself was reportedly in good condition with good braking coefficients. The aircraft appears to be on the ground prior to passing the PAPI lights and wind sock, which would be appropriate. In the video, the engine's thrust reverser panel first moves just after touchdown, but it does not fully open and the outboard spoilers are not visibly deployed. Because of that, things quickly get more interesting.
A full ten seconds after touchdown, the thrust reverser panel moves from barely open to closed. The thrust reverser panel does not begin to reopen, this time fully, until approximately seven seconds later, 17 seconds after touchdown. The engines do not appear to spool up until roughly ten seconds after that. That means the 757 rolls on the runway for 27 seconds before the reversers appear amply engaged. It departs the end of the runway roughly nine seconds later. Pilots who claim to be familiar with the 757 have left comments in professional pilot forums online stating that the thrust reversers on the 757 can sometimes refuse to engage. Others have speculated that a hydraulic problem or a problem with the Boeing's air/ground logic system could have prevented the spoilers, reversers and, most important, the brakes from working properly. For this flight, no one was injured and the aircraft came to rest in packed snow, and still on its gear, about 350 feet beyond the runway overrun area. The NTSB is working the case and should have good cockpit voice and flight data recorder information already in hand. And we'll know if blame will be placed primarily with the crew, with the aircraft, or both.