ACCIDENT, GRAND CARAVAN WAS TOTALED. VAN FLIPPED, EXTENSIVE FRONT END, FRAME, SIDE, ROOF, ETC, DAMAGE. NEITHER OF THE FRONT AIR BAGS DEPLOYED, NOR DID THE SIDE AIR BAGS. PRELIMINARY ASSESSMENTS, INCLUDING QUALIFIED INDIVIDUALS, INDICATE THAT THE AIR BAGS SHOULD HAVE DEPLOYED GIVEN THE EXTENT OF THE DAMAGE. ADDITIONALLY, THE DRIVERS SEAT BELT BECAME DISENGAGED DURING THE ACCIDENT (AT THE CONNECTION BETWEEN BELT TANG AND ANCHORAGE BUCKLE).*JB