Dunno, but if you're sneaky enough you can stow away on one of the Janet Air flights that leave McCarran airport here in Vegas everyday.
Janet Air shuttles employees to and from Area 51 and Vegas. Their planes are unmarked except for a red stripe that runs horizontally all the way around the plane. They look like the 737s that Southwest uses, but they're much more quiet. Even the buses that they take to the airport are all white and unmarked. I see these buses and planes everyday on my way to and from work and their planes fly over UNLV all the time.