Thursday, January 24, 2008

AAIB Update on the British Airways accident at Heathrow

AAIB logoThe United Kingdom's Air Accidents Investigation Branch (AAIB) has issued an update to its initial report on the British Airways B-777 accident that occurred last week at London's Heathrow International Airport (LHR). In that accident, a British Airways Boeing 777-236ER, operating as Flight BA 038, landed several hundred meters short of runway 27L at LHR. Both of the aircraft's engines reportedly failed to respond to throttle inputs during final approach to the airfield, after a flight from Beijing.

Here is an excerpt from the AAIB update, issued on January 23, 2008:
The AAIB, sensitive to the needs of the industry including Boeing, Rolls Royce, British Airways and other Boeing 777 operators and crews, is issuing this update to provide such further factual information as is now available.

As previously reported, whilst the aircraft was stabilised on an ILS approach with the autopilot engaged, the autothrust system commanded an increase in thrust from both engines. The engines both initially responded but after about 3 seconds the thrust of the right engine reduced. Some eight seconds later the thrust reduced on the left engine to a similar level. The engines did not shut down and both engines continued to produce thrust at an engine speed above flight idle, but less than the commanded thrust.

Recorded data indicates that an adequate fuel quantity was on board the aircraft and that the autothrottle and engine control commands were performing as expected prior to, and after, the reduction in thrust.

All possible scenarios that could explain the thrust reduction and continued lack of response of the engines to throttle lever inputs are being examined, in close cooperation with Boeing, Rolls Royce and British Airways. This work includes a detailed analysis and examination of the complete fuel flow path from the aircraft tanks to the engine fuel nozzles.

Further factual information will be released as and when available.
The AAIB update also noted that the wreckage of the accident aircraft "was moved from the threshold of Runway 27L to an airport apron on Sunday evening, allowing the airport to return to normal operations."

Related:  Click here to view all posts on Aircrew Buzz about British Airways Flt 038.