I like this topic

IMO the most top secret part of this research facility is probably under the ground and these underground facilities are all linked together, Groom Lake/Area 51 does have something "secret" going on because from the photos shown on the net you can see huge mounds of concrete/sand just outside the hangar doors so that engine runs can be done in the hanger away from prying eyes, and not forgetting the runway at area 51, its so long it was initially mistaken to be a road, there must be over 30 Air Force bases of all different sizes in that region what must be confusing to the keen UFO Spotter, they would be like “is this Area 51?”
Moving on from the hear say if I was to design a vehicle with super weird technology that was not based around normal aviation engineering principles I would make a "ufo" look like a everyday object like a bus or perhaps a F16, a patron of this site said the best place to hide something is in plain view, well if you saw a bus drive out of area 51 would you think its a UFO?
To conclude I doubt the people who work at area 51 know what’s going on at area 51.