GLANCING SIDE IMPACT HEAD ON COLLISION - VEHICLE ROLLED 270 DEGREES - RIGHT, UPSIDE DOWN, THEN ENDED ON LEFT SIDE. NONE OF THE AIRBAGS DEPLOYED. IMPACT SPEED WAS MORE THAN SUFFICIENT TO ROLL VEHICLE, THUS THEY SHOULD HAVE DEPLOYED. VEHICLE PROCEEDING IN MOTION - PROBABLY 20 MPH AT TIME OF IMPACT ON TWO LANE HIGHWAY (OTHER VEHICLE CROSSED OVER) APPROX 35-40 WHEN FIRST OBSERVED OTHER VEHICLE MOVING ERRATICALLY