[dattaway]

Another perspective how wings are vacuum lifted: vacuum air flow has a low mass, but very high velocity. I work with vacuum packaging equipment and we often see a few 90 turns in the hoses hits the flow like a brick wall at each turn. The speed of the vacuum near 1 torr carries tremendous energy and is enough to rip silicone caulking from inside the joints. Air at double the atmospheric pressure won't see the high velocities to do any damage. I can imagine the high speed downward air flow giving tremendous push.