Elytra Glitch

There is a glitch on the snapshot 15w42a I was trying out the Elytra so, I used the command /tp -1175 70 129 so I could get some air, but I was on the ground with my Elytra and I was going forward without me controlling my player. I was face down and It looked like I was falling but slow, when I jumped I was gliding. Here is some snapshots of it.