Jeremy Zawodny has a good description (with photos) of a mid-air collision between a glider and Hawker (small jet) near Reno. I used to fly gliders in the same area, and I can tell you: It’s pretty wild being above the big jets going into and out of KRNO. My highest altitude: 26,500′. You wouldn’t believe (a) how cold it is up there in an unheated fiberglass ship, (b) how long it takes to get down, and (c) how beautiful the ride is in the mountain wave just east of Heavenly Valley. But as Jeremy wrote, without an operating transponder, the big guys won’t have a clue you’re there.