Stan Evil - sounds logical. But if this is true, how come the people standing at the end of runways don't get squished when a 747 goes overhead.
Good example of how close they can get on
http://www.aviationpics.de/app/app.htm
OK, so it's not a closed system, but even if all the increased pressure were being dissipated over a much larger footprint I'd intuitively have thought the effect directly underneath would still be significant.
As an aside, what happens to the wing loading if a passenger jumps in the air??