Trapped inside a Boeing 737 circling aimlessly in the Greek skies, many of the 121 passengers on board a Cypriot airliner that crashed Sunday probably knew the fate that awaited them. Though the recordings of the cockpit conversations have yet to be examined, the report of two Greek F-16 fighter pilots shadowing the Helios Airways airliner suggests desperate effort to grab the plane’s controls just moments before the crash. When the fighter pilots last glimpsed through the window of the cockpit shortly after 11.25 a.m., they saw two unidentified persons trying to regain control of the plane, the Greek authorities said. Minutes earlier, the fighter pilots also saw «the co-pilot slumped over and perhaps unconscious and the pilot not in his seat,» said government spokesman Theodoros Roussopoulos, adding that the cockpit oxygen masks had been activated. «It seems that the deceased, in most cases, although not all, expired before the crash,» said Interior Minister Prokopis Pavlopoulos, though he cautioned that it was «something we will have to confirm.» Greek aviation experts said yesterday it seemed the plane had a problem with its oxygen supply, starting about 10 minutes after takeoff from Cyprus on Sunday. Greek television reported that autopsies would determine whether the victims died of asphyxiation due to a lack of oxygen in the aircraft. Aviation expert Marcos Kondilakis told Greek television that there seemed to have been «a problem in the oxygen supply.» Greek air traffic controller Manolis Antoniadis said the plane was on automatic pilot when it entered Greek air space and began to turn in circles. «It was out of control,» Antoniadis said, adding that «there had to have been a fast and brutal problem to cause the death of the pilots in the cockpit.» SMS a hoax A claim that a passenger sent a text message to a cousin saying that «the pilot is turning blue» was found to have been a hoax. Late last night Thessaloniki police were questioning a man who claimed to have invented the message as a publicity stunt. The man’s identity was not released, but he is to appear in court today. The head of the crash investigation, Akrivos Tsolakis, said yesterday the plane’s second black box containing recordings of the pilots’ cockpit conversations had been discovered but that it was in a «very bad state.» «We don’t know if we will be able to get something from it,» he said. That and the other black box, the flight data recorder, would be sent to Paris for analysis, under agreement between France and Greece, Tsolakis said. (AFP) Authorities’ response As soon as the fighter pilots reported the pilots of the Helios flight were not in control of the plane, the Defense Ministry ordered a Super Puma helicopter to approach the island of Makronissos and three navy ships to head south of the island of Evia to stand by in the event the aircraft crashed into the sea. The General Secretariat for Civil Defense and the Interior Ministry ordered 47 fire trucks, 200 staff, eight firefighting aircraft and three helicopters to be on alert. Health Minister Nikitas Kaklamanis also put four hospitals in Athens and another in Piraeus on alert. After the plane was reported to have crashed, the Health Ministry’s coordinating agency activated its emergency response plan. Ambulances were sent to the scene of the crash, the first 10 arriving at 12.51 p.m. A total of 35 ambulances were sent to the crash site near Grammatiko, including two vehicles from the medical disaster unit, 10 mobile medical units, two vehicles carrying medical staff, five motorcycles and one administrative vehicle. The National Atomic Energy Commission sent experts to scan for any trace of radioactivity, which was not found. A team of aircraft accident investigators was also sent immediately to the scene. Transport Minister Michalis Liapis approved a request by the US Ambassador to Greece, Charles Ries, to send American experts to assist Greek authorities in investigating the causes of the crash, in accordance with US regulations regarding accidents involving aircraft manufactured in the US.