Pilots overcome in seconds, say experts

THE pilots in the Cypriot airliner disaster could have become incapacitated in seconds, aviation experts said yesterday.

Investigators will want to know why a back-up oxygen supply system for the cockpit crew in the Helios Airways flight apparently failed to work.

Other questions included how the plane appeared to fly for so long with the pilots unconscious or dead.

Defence Ministry officials said 90 minutes elapsed between the alert being raised and the plane crashing at 12:03pm.

Media speculated it was on auto pilot and crashed when it ran out of fuel after being in the air for twice the scheduled flight time.

The investigators may also draw on the case of the October 1999 Lear Jet crash in America in which top golfer Payne Stewart died.

All 121 people on board the Helios flight, including 48 children, are feared dead after an apparent cabin decompression problem caused the Boeing 737 to crash into a hill north of Athens.

It is thought something went wrong with the plane's pressure system which keeps oxygen a breathable levels.

A system failure should have left the cabin crew with a back-up system but it is reported one of pilots was seen slumped unconscious over the controls.

Liz Verdier, a spokesperson for Boeing, said the 737s, like all Boeing planes, were equipped with warning systems that alerted pilots when decompression was occurring.

"The crew could have been overcome very, very quickly if all the systems failed. It may have taken less than 20 seconds," said David Kaminski-Morrow, deputy news editor of internet news service Air Transport Intelligence.

He went on: "The pilots should have had access to a back-up oxygen supply. Planes do sometimes lose cabin pressure and it is a well-practised routine for the crew and passengers to don oxygen masks and for the pilots to take the plane down to an altitude where oxygen levels are all right.

"There could have been something wrong with the bleed system which 'borrows' air from the engines and feeds it into the cabin. Decompression can also be caused by a broken window or a hole in the fuselage."