Hi everyone,
in the FAQs a polar table is given. It should be added that the source is a measurement by Idaflieg at D-0791 somewhat in the 70s or 80s. For a proper use you should know some things:
1) The related wing loading is 27,7kg/m² (5,67lbs/ft²).
2) The measurement has an accuracy of somewhat about ±1,5 of the glide ratio.
3) The measurement was done on a clean glider, its condition should be nearly factory new (of course without WL). Questionable is, if or how the control surfaces were sealed, at which c.g. the glider was flown and also if the pushrods were sealed at the root rib. Shortly: This polar table belongs to D-0791 and can differ from your 15 significantly. Maybe the condition of D-0791 at this measurement could be investigated by asking Idaflieg for old measurement logs...
If I find some time, I'll digitize the factory polar, calculated by Mr. Waibel. Of course it's also very questionable, if this polar represents your 15 correctly
Cheers,
Paul
