Over the winter of 1944/1945 certain Allied POWs were imprisoned in Colditz Castle (east of Chemnitz, Saxony). Some of the British prisoners got desperate enough to build a glider in an attic. They never launched because the war was effectively over by the time the machine was ready, but in 1999, Britain's "Channel 4" TV channel commisioned a replica to be built and flown.
It flew surprisingly well. I've recently been working on a FDM for the Colditz Glider. If you'd like to try it, I've put it up for comments on: ftp://tallyho.bc.nu/pub/steve/flightgear/colditz_20050518.tgz I initially modelled the glider by entering the known physical dimensions of the machine into aeromatic and claiming that it was a "light aircraft with 0 engines" rather than a glider. It was, after all built of floorboards and random junk covered with bedsheets doped with porridge! So, it's rather heavy for its size (110kg/240lb) and was expected to carry two (70kg/160lb) men. My FDM correctly models the stated stall speed of about 28 knots and sink rate of 240fpm. I have personal experience with slow-flying gliders in the shape of early 1980's hang-gliders and so I've added modelling for a fairly serious nose-dive on stalling the glider, plus an entertaining amount of ground-effect to make landings resemble what I recall from the hang-glider days. All the photos and plans of the original Colditz glider show it to have had almost no dihedral on its wings. The photos of the 1999 replica show that this was the case for the copy too. My FDM has taken that into account too, and indeed you'll find when flying it that it's pretty unstable in roll. ************** I would not have liked to have been the pilot who took this thing off the chapel roof in Colditz, at night, on its maiden and only flight. Stall it below 100m (300ft) from the ground and you're dead! It switches from flying like a glider to flying like a piano almost instantly. Oh, and 100m (300ft) is your launch height above the valley floor..... The original glider had no instruments of course. For this model, I've pinched the instruments panel from the Schweizer 2-33 that was already in Flightgear. I did this to give me some idea of airspeed, to compensate for not having the wind in my face whilst flying! I did however re-scale the airspeed indicator to concentrate on the 10 - 90 knot range. ( I suspect that the Colditz glider would fall apart at much higher velocities! ) Disclaimer: This is a toy. It's fun, and probably isn't too far wrong from modelling the real Colditz Glider. However, I've never even *seen* the Colditz Glider replica (in the Imperial War Museum now, apparently) far less flown it. So I don't know. Please try it and if you have any suggestions, I'll be happy to take them on board. I'm expecting complaints about the stall characteristics which are probably too savage, but then, hang-gliders stall hard, so why not this machine? There's no 3D model, sorry. Suggestions for how to do one, or (better) offers of help gratefully received! Enjoy! Steve Hosgood. _______________________________________________ Flightgear-devel mailing list Flightgearfirstname.lastname@example.org http://mail.flightgear.org/mailman/listinfo/flightgear-devel 2f585eeea02e2c79d7b1d8c4963bae2d