A documentary about Korean Airlines Cargo Flight 8509 which crashed after taking off from Stanstead airport in 1999 killing all four crew members on board the Boeing 747-200F. Shortly after liftoff, something caused the plane to bank over harshly causing it to quite literally fall out of the sky. But what made this happen? Was it pilot error, a mechanical fault or something entirely different? The film Aircrash: The Downing of Airlines Flight 8509, aims to uncover the truth in a way we have never seen before, reconstruing the events of that fateful day. This remains one of the worst incidents in British and Korean aviation, fortunately, events like this are extremely rare and since Flight 8509 Korean Airlines has never had anything like it happen again. However, learning from such tragedies