Originally Posted by
EXDAC
My speculation, and it is only speculation, is that turbulence was encountered while a seat swap was in progress and one of those involved in the swap put out a hand to steady themselves and pushed the throttles full forward. Speculation is based on lots of time in flight test where many seats swaps were observed. Who wouldn't have wanted to give the newbie a bit of stick time?
Of course that speculation is meaningless if all crew were found strapped in their appropriate seats.
How about the jump seat passenger simply standing up, perhaps to lean over the pilot's shoulder to get a better look at something? Or coming back from the loo? Or even seated in the jump seat, but perhaps leaning forward with belts off. And they hit turbulence, and he's pitched forward into the controls. Maybe sticks a hand out instinctively, trying to catch himself. Between the startle factor, passenger in the way, trying to regain his feet....