It's a maintenance platform for working on the huge stabilizer of a C-5 Galaxy. You will see one in use sticking out of the hangar to the east in BEV.
Anonymous
@ 2013-12-08 19:39:02
This is a motorized maintenance stand. The stand is casting it's shadow to the upper left. The stand would be driven into position around the T-tail of the C-5 Galaxy.