Awesome! I've been waiting for a Sailplane mod for ArmA 3 since it was in early Alpha :) I fly them in real (unfortunately not the DG1001) but I hope that the flight model is going to be something like the F16 Standalone or F14 because if I try to fly a turn with one of ArmAs standard planes I'm in a side slip instantly. Everyone who has flown a real plane knows what I'm talking about ;) It's probably the most annoying thing to me in the entire game (at least when flying a plane in game).
Sorry for my English. I'm not a native speaker ;)
I hope there will be some kind of thermals added too :)