Could be a training center.

We had simular buildings not exacttly 
like that "hanger" but we would use them 
to train pilots.  It contained mock-up ejection
seats, spatial disoriantation trainers, ground
egress trainers etc.

We also had a live fire ejection seat on rails
depending on the height something simular
might be used.  When I was training pilots
there were always systems I was denied access
too because they were classified higher than my
security clearance.  I even attempted to order
the mauals on certain equipment and was always 
denied it, to include aircraft such as the F-117.