Originally Posted by greg5

This is a good picture showing that this is a plug to cover the door, as opposed to a 'plug door' that closes such that the inside pressure of the cabin keeps the door closed, The following video shows how a plug door operates by being pulled into the fuselage before being swung outside the aircraft. (Note that in this example, the door is wider than the opening). https://www.youtube.com/watch?v=cxzLNBlDVbE