As part of requests concerning the April 19, 1989, explosion aboard the U.S.S. Iowa and other battleship issues, we assessed the Navy's technical investigation of the explosion. The GAO discussed Sandia's preliminary findings in its report BATTLESHIPS: Issues Arising From the Explosion Aboard the U.S.S. Iowa (GAO/NSIAD-90-4, Jan. 29, 1991). This report is Sandia's final report as a supplement to the earlier report. It is concluded that there is no explicit physical evidence that the hypothetical chemical ignition device was present in the center gun of Turret 2. It is also concluded that a high-speed overram is a possible cause of the April 19, 1989, explosion aboard the USS IOWA.