agree with clare prop
I can think of one plane's doors that are structural, it is a system used on the metroliner by swearingen
slang term: click clacks. when door is closed the structure carry through via click clacks which make the door part of the structure.
it is one reason why , in the film "MOONRAKER" only the Handley Page Jetstream could be used in the opening scenes. Taking doors off some planes do cause structural problems...also jumping out of the front door of a metroliner would cause you to be devoured not by JAWS but by the prop.