Heathrow crash landing 'could have been caused by cold weather'
13.05.08
Extreme temperatures caused by cold weather over Russia could explain a British Airways Boeing 777 crash landed at Heathrow in January, flight investigators have said in a preliminary report. Fresh tests are being carried out by both at Rolls Royce’s engine plant at Derby and the Boeing’s factory in Seattle to recreate what happened on the flight from Beijing to test the theory.
One passenger suffered serious injuries and 12 others on board British Airways Flight 38 were slightly hurt when the jet failed to reach the runway on January 17. The plane was wrecked beyond repair. In its latest report on the incident, the Air Accidents Investigation Branch has focused on the ‘region of particularly cold air’ between the Urals and Eastern Scandinavia. It found that temperatures plummeted to -76C, far lower than would have been expected.
Experts are now examining whether this could have led to a thickening of the fuel, which led to neither engine receiving the necessary power during the final stages of its descent into Heathrow. They suspect that the plane's fuel flow became restricted somewhere between the engines and the fuel tanks.
The investigation has homed in on fuel flow as the key issue that led to the crash landing after the AAIB ruled a number of theories that had been floated in recent months including bird strike and ice in the engine. Its experts have also discounted electromagnetic interference from jamming devices which were claimed to have been used to protect the Gordon Brown’s motorcade as he arrived at Heathrow.
The experts have also established that the fuel used on the aircraft was of high quality. While the average freezing temperature of aviation fuel is -47C, tests on what was on this flight showed that it did not turn to ice until -57C. Tests also found that the fuel temperature throughout the flight never dropped below -34C. But even though the fuel did not turn to ice it could have thickened to an unusual extent, which could have restricted the flow.
A spokesman for Rolls-Royce, which made the plane's engines, declined to comment. Spokesmen for Boeing and British Airways also declined to comment, citing company policies against making public statements before investigators have concluded their work. However, David Learmount, operations and safety editor at Flight International, was critical of the update. He said: 'This report takes us absolutely nowhere, I think they still have no idea.’
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