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, Nicosia air traffic control (ATC) lost contact with the pilots 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.