Friday, January 18, 2008

Capt Burkill praises crew of crashed jet

The captain of flight BA-38 which crash landed at Heathrow yesterday paid tribute to his crew for excellent teamwork. Capt. Peter Burkill said his co-pilot, John Coward, was at the controls at the time of the incident. He also thanked the passengers for their calmness in a difficult and unfamiliar situation. He wished everyone who received injuries a speedy recovery. He did not talk about what happened in the last minutes of the flight saying that the crash was now a matter of investigation by the AAIB [BBC].

Those investigations may well focus on the electronic systems on the plane. Some reports suggest a major power failure just prior to the crash. The Boeing 777 has a relatively good safety record. However it has only been in service for 14 years. There have been some incidents with the Boeing 777 but no fatalities have yet resulted. Perhaps the most concerning incident was in 2005 when there were conflicting displays of information displayed in the cockpit. The results of the investigation into that incident have yet to be completed [ but preliminary report does raise concerns.

On August 1, 2005, a Boeing 777-200, which had departed from Perth, received an EICAS (Engine Indication and Crew Alerting System) warning of low airspeed, as the plane was climbing through FL (flight level) 380. Simultaneously, the aircraft’s slip/skid indication moved full right, on the PFD (Primary Flight Display). The PFD speed tape also displayed contradictory information: that the plane was approaching both the high speed limit and the low speed (stall) limit. The aircraft, still connected to the autopilot, pitched up and climbed to approximately FL410 as the airspeed decreased from 270 kts to 158 kts. The stall warning devices also activated.
The PIC (pilot in command) "disconnected the autopilot and lowered the nose of the aircraft. The autothrottle commanded an increase in thrust which the PIC countered by manually moving the thrust levers to the idle position. The aircraft pitched up again and climbed 2,000 ft." The PIC advised ATC "that they could not maintain altitude and requested a descent and radar assistance. The crew was able to verify with ATC the aircraft speed and altitude."
The PFD indications became accurate again as they were descending through FL200. The PIC attempted to use both the left and right autopilots, but had to turn them off after each one produced undesired command responses. "There were no control difficulties experienced when the aircraft was flown manually, but the autothrottle `arm’ switches remained in the `armed’ position." [PDF].
The Boeing 777-236ER involved in Thursday’s incident has not had any previous problems itself. But investigators will also be looking at the Rolls Royce engines.

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