Working as an air traffic controller for sixteen years, I have had my share of unique situations develop and this is one of my more memorable and fortunately it turned out good. I was working a high altitude sector at Memphis Air Route Traffic Control center and had a single F-16 check in at flight level 390 (39,000ft) heading west. After an uneventful trip through my sector, I tried to switch him over to the next sector but got no response. After a couple more tries I called the sector to see if he had shown up (both ours and their UHF radios leave a lot to be desired), which he hadn't. So after a couple of calls on UHF emergency frequency with no response I figured he would show up when he wanted lower, which would be soon. After a few minutes a voice came over the radio, "center Slam11" ( The callsign has been changed to protect the sleepy).

Tower: "Slam11, Memphis center, go ahead."
Aircraft: "center Slam11 is a two seat F-16, the pilot is unconscious and I am the flight surgeon."
center: "Slam11, understand the pilot is unconscious and you are not a pilot?"

Aircraft: "I am a pilot but not in this airplane!"
I asked him if he could make a 180 degree turn so I could keep him on my scope and also maintain radio coverage. He said he could an began a very slow right turn.
After turning about 30 degrees right, his turn stopped and I tried calling him but got no response. Just before he was about to get to the edge of my scope he called.
Aircraft: "center Slam11, I got the pilot's mask back on and he seems to be coming around."
center: "OK, I need you to continue the right turn around before I lose you."
After a short pause he came back.
Aircraft: "center Slam11."
center: "Slam11, go ahead."
Aircraft: "Slam11 request a snap (vector) direct McConnell."
center: "Is the pilot conscious?"
Aircraft: "This is the pilot."