The one with the glider was the third book in the series. The second one is Mr. Reids own story as a "guest" in Colditz, and climaxed in his own escape back to Britain after numerous attempts.
The first one is the history of Colditz, and the early years of WWII as a POW camp, and trying to keep all the bad-boys in 8)
If you can get them they are an excellent read, the second one I enjoyed the most as an autobiographical account of life there and how they tried to escape (some of those ideas were hair-raising )

Mark