I had something similar happen about 6 years ago, landing on my face, sans helmet when the front wheel came off going downhill. It was my fault though, I didn't put the wheel on tight enough. Flew over the handlebars and got hit in the back by the bike catching up with me. Worse was the fact that I was going to meet a cute bicycle courier from Calgary. At least she understood, even though my face was all bloody and I couldn't really walk straight. The only good that came of it was that the Bike Doctor in Missoula Montana replaced my bent up fork with a sweet looking homemade fork they had lying around, a great improvement. Just remember check those quick releases.