F-16 pilots saw F/A Andreas Prodromou at controls, (trainee pilot), attempting control of aircraft, (consciousness due to portable oxygen)
The Greek Governmental Investigation Board determined that the crash of Helios 522 resulted from the flight crew not setting the pressurization system in normal (automatic mode) before take-off. There was a gradual decompression, all on board suffered from Hypoxia. Because of mental incapacity, the flight crew did not respond to the warnings, symtoms of hypoxia were not recognized.
Timeline of Events
9:00 a.m. — Helios Airlines Flight ZU522, a Boeing 737 carrying 115 passengers and six crew members, takes off from Larnaca International Airport in Cyprus, heading for Prague, Czech Republic, with a stopover in Athens.
9:37 a.m. — Plane enters Greek air space, identified by Greece's Civil Aviation Authority.
10:07 a.m. — Control tower at Athens International Airport unable to establish communication with the plane.
10:20 a.m — Air traffic controllers notify Cypriot counterparts who say plane reported a problem with air-conditioning system before entering Greek airspace.
10:25 a.m. — Greek Civil Aviation Authority notifies Defense Ministry's national search and rescue center.
10:30 a.m. — Defense ministry issues a Renegade alert, standard aviation procedure when planes fail to respond to control tower.
10:55 a.m. — Two F-16 fighter jets scramble to locate airliner.
11:20 a.m. — Fighter jets make visual contact with airliner over Aegean island of Kea, but unable to communicate with pilots.
11:25 a.m. — Fighter jets approach plane, report that co-pilot appears unconscious, other pilot not in cockpit, oxygen masks dangling inside cabin.
12:05 p.m. — Airliner crashes near town of Grammatiko, about 25 miles north of Athens.
All 121 people on board were killed
