olasek:
And no thunderstorm is even needed to fall from the skies.
China Airlines 747 flight 006 plummeted from FL410 to 11000 feet over Pacific, they barely recovered, at some point they were even upside down (!), they landed in SFO with parts of the aircraft missing. And the cause - pilots badly mishandled an engine failure.
On autopilot at cruise. No one minding the store. The engine failed and the autopilot tired to compensate, until it couldn't.
As I recall one of the pilots was out of the cockpit and the events overwhelmed the other pilot and F/E.