Originally Posted by
EddyCurr
You are saying that in-flight repositioning of an object with the dimensions and aerodynamics of an A321 cabin door, one that has to extend outward from the hull and articulate forward to fully open, is a trivial matter?
I think the point is that it does NOT have to "articulate forward" to open, assuming that that means swinging like an ordinary door on a hinge. As far as I can see the door moves outwards a little, presenting its edge to the airflow, and then translates forward like a sliding door. I don't know how to calculate the forces, but they'd evidently be lower than if the door just swung out like an airbrake.