It's a fake. If you look closely, you can tell by the shadows when the plane is on the ground and the lack of whatever was painted on the nose. In the footage that really does show the stunt plane, it has something clearly written on the nose but when it's on the ground there is nothing there. Plus, while some stunt planes that have a high thrust to weight ratio are capable of 'knife edge' flight, I don't think it would be possible with only one wing. However, RC planes (like the one in the video) are quite capable of doing this maneuver rather easily.
ack-ack
