physics in doing a licoln loop

When executing a lincoln loop while skiing, surprisingly physics is involved. When taking off on the jump, there is friction slowing you down, the friction is between the bottom of your skis and the snow. Also when you are in the air, gravity is pushing you down. Also when you land, to an observer about 60 yards away, it appears as if you land and then you hear the sound of you smashing down onto the snow seconds after you land. This is because light travels faster than sound.