Area 51 is the number assigned to the airspace over Groom Lake, the base on the ground.
People should know better.
You enter Area 51 airspace you get locked up somewhere for a few weeks while they interview you. Same if you penetrate Groom Lakes ground perimeter.
Ive flown Red Flag and a military air crew accidentally entered the airspace, were met at Nellis by guys in suites, were put in a van with no windows and were driven for a couple hours, got out in an under ground garage, questioned for a few hours, put in a room with bed and bath and were isolated for gawd knows how long. Then back in the van and then were delivered back to Nellis.
I had just gotten back from Korea and was with 3/5 Cav at Ft Lewis for about two weeks. We went to Nellis for Red Flag. I was an E-5 at the time and was put in charge of the Forward Area Arming Refueling Point for the night. The FAARP was somewhere in Tonopah range, about an hour and change by Blackhawk. A little after arriving, a civilian security guard came to look at our badges. Mine wasn’t on his list. Into the truck and an hour drive to some shack. I was there for a couple of hours until someone at Langley verified who I was. Another hour back to the FAARP only to find my PFC and SP4 digging a foxhole inside the tent. But that’s another story.
Reminds me (a bit) of The Disappearance of Flight 412 (1974)
Some USAF guys monitoring a flight see a aircraft chasing something disappear and are brought to a remote installation for "debriefing".