The captain was insane. Probably killed his first officer. Depressurized the aircraft thus killing everyone else as he was on oxygen. Flew it South and into the Indian Ocean when out of fuel.
“The captain was insane. Probably killed his first officer. Depressurized the aircraft thus killing everyone else as he was on oxygen. Flew it South and into the Indian Ocean when out of fuel.”
Locked the First Officer out of the flight deck.
My favorite theory is that both the Captain and First Officer left the flight deck but locked the keys inside.
“Do you got the key?” “No, I thought you had the key?”
Or both forgot the passcode.