Helios 737 tried to send Mayday

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Crash investigation reveals flight attendant attempted unsuccessful distress call to air traffic control

It has emerged that the non-pilot who sat at the controls of the doomed Helios Airways Boeing 737-300 tried unsuccessfullyto contact air traffic control for assistance.

Preliminary conclusions from the investigation into the 14 August fatal accident published last week confirm that the aircraft crashed after running out of fuel, following an unidentified pressurisation problem (Flight International, 23-29 August). All 121 people on board the Larnaca-Athens flight, which crashed north east of Athens, were killed.

Fighter aircraft sent to escort the 737 as it approached Athens had determined that the captain’s seat was empty and that the co-pilot was apparently unconscious. But there is evidence, says Greek chief investigator Capt Akrivos Tsolakis, that a man with an oxygen mask – believed to be the person previously identified to Flight International by Tsolakis as a male flight attendant with a “few hours” private pilot training who took the controls of the 737 after the pilots’ incapacitation – tried at least twice to send a Mayday call. Tsolakis adds that the tone of voice used showed that the individual was either distressed or suffering from exhaustion.

The call was made in such a way, however, that it “could not be picked up by any station”. It is known that the communication system was operating during the last 30min of flight – as there are recordings of transmissions of other aircraft – so investigators are studying whether the radio was left tuned to the frequency of Nicosia air traffic control as the jet left Cypriot airspace.

Meanwhile, France’s air accident investigation department, the BEA, has been tasked with analysing the 737’s cockpit voice recorder (CVR), recovery of which had been delayed because its recording system and protective shell had separated from its main casing at the moment of impact. But the BEA says: “There was no trace of fire and [the CVR] was only slightly damaged.”

The BEA is also examining data from a depressurisation incident on board a UK-operated 737-300 that occurred five days after the Helios crash, to see whether the information could assist the Helios probe. The Astraeus 737, flying from Mahon, Menorca to Leeds-Bradford with 144 passengers and six crew, made an emergency descent from 36,000ft following a technical problem with the pressurisation system. Both pilots were on oxygen and passenger masks deployed automatically. The aircraft diverted safely to Brest.

DAVID KAMINSKI-MORROW/LONDON