I was lucky (or unlucky) to get to guard the shuttle when it was being sent back to Fl back in the early 90's. The shuttle would stop lots of times at Biggs Army Airfield where I was stationed. We were tasked with guarding the beast while the crew took a break or waited out weather.
It is funny to see 12 soldiers standing around the shuttle with M-16's. The thing that made it so funny, we were not issued any ammunition, just an empty clip!

I guess we could have clubed the would be attackers of the shuttle with our weapons
I have some great close up pictures somewhere I should dig up.