Boeing 777: Safety fears over crash jet's alarm failure - by Dan Milmo and Sam Jones
The pilots of the British Airways Boeing 777 that crash landed at Heathrow on Thursday received no warning that the aircraft was losing power because of a problem with the aircraft's alarm systems, a source has told the Guardian. Because there was no signal from the Boeing 777's automatic warning system, the pilots did not realize anything was wrong until they approached the runway and noticed the plane was losing speed more rapidly than normal. The plane "fell out of the sky" just 10ft from the ground after stalling as it came in to land.
The fact that the pilots, Captain Peter Burkill and senior first officer, John Coward, did not receive an automated warning of the drop in engine power will cause concern about the safety of systems on the 777 of which more than 600 are in service. Although all commercial airplanes have programmed "inhibitions" on certain warnings so that the crew are not distracted by unnecessary alarms during the crucial takeoff and landing procedures, the alarm should have been triggered when the engines failed.The Guardian has also learned that a key instrument, the engine pressure ratio gauge, which tells the crew how much power is available, had failed. The pilots tried to coax more power from the 777, but it did not respond, according to an aviation source. Realising every ounce of lift would be needed to nurse the plane over Heathrow's perimeter fence, Coward, who was at the controls, dropped the nose to maintain speed. As he approached the fence, he lifted the nose, wringing the last reserves of energy from the plane. Then the aircraft narrowly missed a guidance beacon before stalling around 10ft from the ground. "It just fell out of the sky from a few feet," said the source. "It was the skill of the crew that kept those 136 people alive."
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