Simple you get a British Diplomatic Wife to drive on the road into Area 51. She waves her Diplomatic ID at everyone. Comes back to tell us what is there. Oh and as Gladys can tell her right from her left no US citizens are harmed. If US asks for her to face music RAF fly her home.Job done.
GA pilot flies on edge of the ‘box’ (with permission ) and takes pics in todays news... guess he didn’t need reception in the air or on the ground.
A private pilot had one heck of an adventure through the Nevada Test and Training Range, getting very rare looks at the shadowy installations.www.thedrive.com
Back during the 2000s, the USAF apparently tried to move some of it's testing and developmental work out to Utah. Didn't come off for some reason.
I recall an incident where a Canadian military aircraft was in trouble and called the non-existent tower at Area-51 to request permission for an emergency landing. It was granted. The plane was met by an officer and base security. The airplane was checked for cameras. The pilot was informed that if they get in trouble again they would be shot down. Nice chaps I'm sure.