YouTube

Zitat

Video shot by a passenger aboard American Airlines Flight 2253 as it overran Ruwnay 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 am. About seven inches of snow had fallen in the area since midnight. The aircraft appears to be on the ground prior to passing the PAPI lights and wind sock. One pilot who commented on pprune.com suggested that places the landing point approximately 1,400 feet down the runway. In the video, the engine's thrust reverser panel first moves just after touch-down, but it does not fully open and the outboard spoilers are not visibly deployed. Because of that, things quickly get more interesting. Click through for the video.

A full ten seconds after touch-down, the thrust reverser panel moves from barely open to closed. The thrust reverser panel does not begin to re-open, this time fully, until approximately seven seconds later, 17 seconds after touch-down. 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 after that. 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 and reversers 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.

Zitat

December 31, 2010 - The National Transportation Safety Board has opened an investigation into an incident in which a passenger jetliner that had landed at Jackson Hole Airport in Wyoming failed to stop after touchdown on Thursday.

At about 11:38 AM MT on Thursday, American Airlines Flight 2253, a B-757 (N668AA) inbound from Chicago O'Hare International Airport, ran off the end of runway 19 while landing at Jackson Hole Airport. No injuries were reported among the 181 passengers and crew on board.

The pilot reported that the braking system failed. Flight 2253 continued down the runway, passing the end of the runway and through the runway overrun area which was 300 feet. The aircraft finally came to rest about 350 feet from the overrun area in hard packed snow.

The pilot came on the intercom to reassure passengers that they were ok and stated that the brakes weren’t working properly. Airport officials brought in heavy plows and airport workers began plowing an area around the Boeing 757. A portable staircase and buses were brought in and it took just under an hour before all 181 passengers and crew were able to disembark the aircraft.

Aircraft can and do overrun the ends of runways, sometimes with devastating results. An overrun occurs when an aircraft passes beyond the end of a runway during an aborted takeoff or while landing. To minimize the hazards of overruns, the Federal Aviation Administration (FAA) incorporated the concept of a safety area beyond the runway end into airport design standards called “runway overrun area”.

To meet the standards, the safety area must be capable, under normal (dry) conditions, of supporting the occasional passage of aircraft that overrun the runway without causing structural damage to the aircraft or injury to its occupants. The safety area also provides greater accessibility for emergency equipment after an overrun incident. There are many runways, particularly those constructed prior to the adoption of the safety area standards, where natural obstacles, local development, and/or environmental constraints, make the construction of a standard safety area impracticable.

.......
The weather was reported to be snowing at the time of the incident. No damage to the aircraft has been reported. Senior NTSB Air Safety Investigator Joseph Sedor has been designated as the Investigator-In-Charge. At this time parties to the investigation are American Airlines, Boeing, the Allied Pilots Association and the Federal Aviation Administration.

Zitat

NTSB Advisory
National Transportation Safety Board
Washington, DC 20594
December 31, 2010

NTSB ISSUES UPDATE ON JACKSON HOLE B-757 RUNWAY OVERRUN INCIDENT

In its continuing investigation of the runway overrun of a jetliner in Jackson Hole, Wyo., the National Transportation Safety Board has developed the following factual information:

At about 11:38 am MT on Wednesday, December 29, American Airlines flight 2253, a B-757-200 (N668AA) inbound from Chicago O'Hare International Airport, ran off the end of runway 19 in snowy conditions while landing at Jackson Hole Airport. No injuries were reported among the 181 passengers and crew on board.

The aircraft came to rest in hard packed snow about 350 feet beyond the runway overrun area. An initial inspection did not reveal any structural damage to the aircraft. Shortly after the aircraft came to a stop, in accordance with American Airlines' procedures, the pilots pulled the circuit breaker to the cockpit voice recorder (CVR) to preserve all of the recorded information for investigators.

The CVR and DFDR (digital flight data recorder) arrived at the Safety Board's recorder laboratory on Thursday evening, Dec. 30, where investigators were standing by to download the contents of both recorders. The CVR provided a two-hour recording of excellent quality audio; the voices of each of the pilots on the flight deck were clearly audible. The DFDR provided 1200 recorded parameters of flight data and captured the entire incident.

The crew, who were interviewed on Thursday evening, indicated that they saw the runway prior to reaching the minimum descent altitude before touchdown. Both crewmembers characterized the flight and approach to landing as uneventful prior to the runway overrun. The first officer was the flying pilot.

The accident docket, which will contain additional factual information, is expected to be opened in 60-90 days. It will be available on the docket section of the NTSB website at http://go.usa.gov/rjR

PROTOCALS FOR TRANSPORTING AIRCRAFT RECORDERS IN INCIDENT INVESTIGATIONS

The Safety Board has long-established protocols for the handling and transportation of CVRs and DFDRs that contain recorded information from a commercial aviation incident, which by definition is one where no serious injuries or substantial damage to the aircraft or other property has occurred.

In such incident investigations, the Safety Board frequently asks the airline involved to transport the recorders on their own aircraft as such an arrangement often provides the most expeditious means of conveying the devices to Safety Board labs in Washington. The airline is instructed to transport the recorders without delay and without accessing the information contained within them by any means. This practice has worked efficiently and without complication for more than 40 years.

During this incident investigation, the Safety Board learned that the recorders were flown to Tulsa, Okla., where American Airlines technicians downloaded information from the DFDR; the CVR was not accessed by American.

"Although a thorough examination by our investigators determined that no information from the DFDR was missing or altered in any way, the breach of protocol by American Airlines personnel violates the Safety Board's standards of conduct for any organization granted party status in an NTSB investigation," said NTSB Chairman Deborah A.P. Hersman. "Because maintaining and enforcing strict investigative protocols and procedures is vital to the integrity of our investigative processes, we have revoked the party status of American Airlines and excused them from further participation in this incident investigation."


American Airlines has assured the Safety Board that a full review of proper procedures and internal controls would be undertaken to ensure that such an occurrence is not repeated.

Despite their removal from party standing, the NTSB will provide American Airlines with any and all information needed to ensure a timely response to operational safety deficiencies identified in the course of the investigation.

Zitat von »Flugzeugschrauber«

Die Reverser benötigen dieses Signal nicht zwangsläufig, sondern lassen sich schon bei RA <10 feet betätigen