A Cypriot plane that crashed in Greece killing all 121 people on board likely suffered a catastrophic air-pressure problem before running out of fuel, the head of the Greek investigation team said on Monday.
Akrivos Tsolakis also said that someone tried to land the stricken aircraft after its pilots were incapacitated and twice tried to send a distress signal but never got through.
His remarks, contained in a letter to Greece’s transport minister and made public on Monday, shed some more light on the technical elements and human drama behind the August 14 tragedy.
”There are signs of a technical anomaly in the aircraft’s pressure system,” Tsolakis wrote in the letter. ”If this happened, then it would have had an impact on the physical condition of the passengers and crew.”
Tsolakis said there is evidence lack of fuel was the ultimate cause of the Boeing 737 slamming into a wooded hillside north-east of Athens.
The investigation team has already established that its German pilot had signalled a fault with the air-conditioning system in the plane’s electronics compartment to his company shortly after take-off from Larnaca in Cyprus.
It is unclear what incapacitated both pilots, who did not operate emergency procedures.
Tsolakis confirmed earlier reports that someone had attempted to land the stricken plane, based on evidence drawn from the voice recorder of the Helios Airways jet.
”There is proof … that a person wearing an oxygen mask was sitting in the pilot’s seat for the final 10 minutes [before the crash],” Tsolakis wrote.
”This person twice attempted to send a Mayday signal, in a fashion that could not be picked up by any station. The tone of voice showed that it was a man, either distressed or suffering from exhaustion,” he said.
Findings so far disprove the theory that the Boeing’s communications systems had also been knocked out.
”There are signs that the communication receiver was operating in the last 30 minutes of the flight, as there are conversation recordings of other aircraft,” Tsolakis said.
The pilots of two F-16 fighter jets sent after the airliner reported seeing the co-pilot slumped in his seat, the chief pilot missing and two people in the cockpit appearing to be trying to regain control.
Commentators believe the man at the helm was Andreas Prodromou (25), a trained small-aircraft pilot who was standing in as cabin crew.
Though his body has not been identified, his blood was found on the plane’s rudder control, according to police.
Tsolakis said investigators are studying whether the unidentified man in the cockpit was unable to communicate because the receiver might have been in the wrong position.
Decompression could help explain what knocked out the pilots, resulting in hypoxaemia, or lack of oxygen in the blood, one of the investigating coroners said on Monday.
”With hypoxaemia … there is swift transition to a state of lack of judgement and euphoria … in a matter of seconds,” coroner Nikos Karakoukis, one of seven experts conducting autopsies, told private Skai radio.
”If the technical search shows there was decompression [in the cabin], then there was definitely hypoxaemia.”
The crash was the worst aviation disaster to befall Cyprus or Greece. Those killed were almost all Cypriots.
In Nicosia, officials said on Sunday they were examining whether Helios should have been granted an operating permit, after a report that the international body overseeing air transport had objected to a licence for the company when it was established in May 1999.
A Cypriot police investigation is under way to ascertain if the company was negligent in any way.
Helios has continued to fly but says its remaining Boeing 737s will undergo ”complete mechanical checks” in Sweden. Tests are earmarked to be completed by August 24 and Helios schedules are expected to be disrupted until then. — Sapa-AFP