Helios Airways Flight 522

Helios Airways Flight 522 was a scheduled passenger flight from Larnaca, Cyprus, to Prague, Czech Republic, with a stopover in Athens, Greece. Shortly after take-off on 14 August 2005, air traffic control (ATC) lost contact with the aircraft operating the flight, named ''Olympia''; it eventually crashed near Grammatiko, Greece, killing all 121 passengers and crew on board. It is the deadliest aviation accident in Greek history.

An investigation into the crash by the Air Accident Investigation and Aviation Safety Board (AAIASB) concluded that the crew had neglected to set the pressurization system to automatic during the take-off checks. This caused the plane not to be pressurized during the flight and resulted in nearly everyone on board suffering from generalized hypoxia, thus resulting in a "ghost flight". The negligent nature of the accident led to lawsuits being filed against Helios Airways and Boeing, with the airline also being shut down by the Government of Cyprus the following year. Provided by Wikipedia