Is a glider basically joinked into the air by a large and fast winch, and then detached and the glider glides on it's own "power" back to the landing? Or is the winch at the destination, with a cable going _all_ the way across the landscape to where the launch point is, so that it can pull the glider over?
I'm a tad confused.
On a day with a decent breeze, it is possible to "kite" a glider up to very high altitude by letting the wire out again. But this is highly frowned upon because it means there is a very long (and nearly invisible) wire dangling right through the airspace used by other aircraft!
Cable falls can be a problem. A cable falling over power lines causes all sorts of fuss!
Cable breaks can be terrible. The cable will spring back, whip around, and is incredibly destructive - hence the cage around the winch operator. I would not have been standing anywhere nearby and certainly not next-to or behind the drum.
Edit: so yes, your first thought is correct. :) It's somewhat similar to an aircraft carrier launch except that the glider can get a lot more altitude out of it.