A TOYOTA YARIS WAS INVOLVED IN A HEAD-ON COLLISION WITH AN AUDI TT. THE YARIS EXPERIENCED A DELTA-V OF APPROXIMATELY 60 MPH. POST COLLISION INSPECTION OF THE VEHICLE REVEALED THE YARIS' DRIVER SEAT ROTATED 90-DEGREES COUNTERCLOCKWISE. THE BOLTS WHICH FASTENED THE SEAT'S MOUNTING BRACKETS TO THE FLOORBOARD HAD ALL BEEN SHEERED OR PULLED OUT OF THE FLOORBOARD. *TR