Crash: Toxic gases to blame?

2005-08-14 20:04

Paris - A pressurisation failure could not on its own have caused the crash of the Cypriot airliner killing 121 people on Sunday near Athens, French aeronautical experts said.

"A failure of pressurisation could not cause an aircraft to crash.

"It is impossible that after a loss of pressurisation the plane could not be recoverable," aircraft accident expert and pilot Francois Grangier told AFP in Paris.

Greek authorities suggested the failure of pressurisation in the aircraft may have caused the crash when they ruled out a terrorist attack.

Grangier said the plane would have been at fairly low altitude as it approached Athens airport, and that a loss of pressurisation would not have had any effect on the aircraft's structure, nor would it have made the pilots immediately lose consciousness.

He also said the pilots would also have had their own oxygen supply.

Pilot 'turned blue'

Grangier noted that oxygen masks allow those on board to breathe while the plane descends to an altitude which allows normal breathing, at about 2 000m to 3 000m.

A passenger aboard the Helios Airways twin-engine Boeing 737 had time to send a text message to a cousin saying that the pilot had turned blue and "we're going to die", a private Greek television station reported.

"We're cold. The pilot is blue. We're going to die. Farewell," the message said, according to Sotiris Voutas, the cousin who contacted the Alpha TV station.

Two Greek air force F16 fighters that scrambled to investigate after the plane lost contact found it drifting above the Euboea peninsula northeast of Athens and saw the pilots slumped over in the cockpit.

The plane crashed minutes later.

Another aeronautical expert, Gerard Feldzer, said the most likely explanation was that at the time of the crash the pilots had already loss consciousness and the plane was on automatic pilot.

Toxic gases

"This seems to have been observed by the pilots of the F16. Otherwise I don't see how a simple depressurisation could lead to an accident," he said.

"We could imagine an intoxication of the pilots by the air-conditioning system, that's to say that something must have burned in the air ducts which took toxic gases into the cockpit - perhaps odourless - which caused the loss of consciousness."

However Feldzer said this would be the first air accident of this type.

"There have been problems of depressurisation, faults in air-conditioning, breathing of noxious fumes, but that has never led to an accident," he said.

- AFP