Cyprus plane sent 'Mayday' before crash

An exhausted-sounding man sent last-minute Mayday calls from a Cypriot airliner that crashed earlier this month, Greek officials investigating one of civil aviation's most baffling incidents said yesterday.

The Helios Airways Boeing 737 crashed on August 14 into mountains near Athens, plunging from around 10 kilometres up to kill all 115 passengers and six crew in Greece and Cyprus' worst air disaster.

The cause of the crash is a mystery - the plane had flown for 2-1/2 hours without making radio contact. F16 fighters scrambled to investigate had reported seeing no pilot present and a seemingly unconscious co-pilot slumped in his seat.

As Helios started safety checks in Sweden on its remaining Boeings, the crash's chief investigator said a steward who had some flight training was thought to have made the last gasp cry for help from the plane's cockpit.

In a letter to Greece's transport ministry, Akrivos Tsolakis also said the Boeing crashed after the engines stopped, a possible signal the plane ran out of fuel after flying for nearly twice the scheduled 90 minute flight from Larnaca in Cyprus to Athens, a stop on the way to final destination Prague.

"There are signs there were problems with the compression system," Mr Tsolakis said in the letter, read out on state TV.

"There is proof that the engines stopped working, causing the plane to drop."

Police have confirmed steward Andreas Prodromou, who was learning to fly small planes, was inside the cockpit and appeared to be trying to fly the plane for about 30 minutes before it crashed.

"The man who sent the Mayday calls sounded tired and exhausted," the letter said.

Greek media reported Athens control tower did not pick up the warnings because they were transmitted on a wrong frequency.