GAO discussed the explosion aboard the U.S.S. Iowa, focusing on: (1) an independent investigation of the Navy's technical analysis of the explosion; (2) equipment serviceability and safety; (3) manning and training issues; and (4) the battleship's employment plans and mission. GAO found that: (1) the Department of Energy's Sandia National Laboratory concluded that there was a plausible alternative scenario to the Navy's finding of an intentional act; (2) as a result of Sandia's findings, the Navy halted all firings of the 16-inch guns and initiated further testing; (3) the Navy and Sandia believed that the ban could be lifted by using a different propellant configuration and taking different management actions; (4) Sandia could not confirm or deny the Navy conclusion that foreign material residue found in the gun was evidence of a chemically activated detonator device; (5) the Navy's need to maintain two battleships was questionable; (6) there was no pattern of failures that indicated systematic problems with the guns and other turret equipment; (7) injury reports revealed no prior safety problems that could be related to the explosion; (8) Iowa personnel failed to follow approved procedures to ensure the safe firing of guns and improperly approved and conducted gunnery experiments; and (9) the Navy deployed the Iowa with significantly lower percentages of authorized supervisors and turret-related journeymen.