Dog flies a glider, it launches by sliding down hill.
Dogs can ride snow sleds and control skateboards. (see links)
They should be able to fly gliders as well. Basically a snow sled with wings.
I'm also thinking it might be possible for them to get a rolling glider up to speed on a flat surface, jump on it and shift their weight so it aims the wing equipped skateboard up long enough to do a short glide.
No ailerons, too heavy, just the twist wing control surface like the Wright Flyer used.
Now you'd probably need the pooch to launch into a good enough headwind but it would be flying dogs, which is after all, the goal here.