I would give hambone one point for the AB explanation and Whalerboy a half point for the “on purpose” comment. Not that I’m know anything what so ever about the subject and don’t even know what I’m here!
Do they often refer to the tail of an aircraft as “the butt of the plane?” Huh, I can only imagine being on the phone with Southwest airlines and the nice young lady on the other end telling me, “sir the only seats we have left are in the butt”.