My dads plane was just opposite those on Friday.
They actually flew one of them in the show on Friday... (Whoa Quiet) and then put it back on display.
There were 2 armed American gaurds for each plane, and a double fence deal around each one.
They also had special demands and such for moving the aircraft... American personel were on the tugs driving and guiding the aircraft, and no other aircraft were to be moved at the same time as the 117s were being dragged back to the hangers.
Pretty neet to see one so close and definitely cool to see one fly... must have been a PITA for the tower to bring them in though... they picked up my dads little plane at 5+ kms out on the Radar.. I bet they didn't even see the F117s until their gear went down ;D