The USS Iowa was participating in firing exercises during maneuvers with the US Second Fleet, about 300 miles northeast of Puerto Rico. A 3-gun salvo was ordered for Turret Two. Turret Two's right and left guns were load and ready. It was reported over the turret's phone circuit that the center gun was having problems, they weren't ready yet. At 9:53am, the center gun in Turret Two exploded, killing all 47 crew members and severely damaging the gun turret. It buckled the bulkheads separating the center gun room from the left and right gun rooms. A fireball spread throughout the gunrooms and the lower levels of the turret. Burning polyurethane foam released cyanide gas, and other toxic gases filled the turret. The heat and fire ignited 2,000 pounds of powder in the powder-handling area of the turret. A second explosion occurred approximately 9 minutes after the initial explosion, most likely due to a build up of carbon monoxide gas. Twelve men in the bottom of the turret were able to escape without serious injury. The automatic sprinkler system in Turret Two failed to operate. Firefighting crews sprayed the roof of the turret and the still loaded right and left guns with water. An inspection of the powder flats in the turret determined that several tons of unexploded powder bags were "glowing" and the turret was flooded with seawater to prevent the powder from exploding. The Iowa returned to Norfolk, VA on April 23. On April 24th, a memorial service was held, attended by family members and several thousand people. President George H. W. Bush, and his wife, Barbara, were among the dignitaries present. President Bush spoke and afterwards met with the family members of the fallen crewmen. An independent review and investigation by Sandia National Laboratories determined there was an overram of the powder bags as they were being loaded and the overram may have caused the explosion. The bronze plaque has a rendering of the USS Iowa and lists all 47 names of the fallen crewmen. The plaque is set in marble and is on a stone pedestal base. It is at Iowa Point on the Norfolk Naval Base, and overlooks the Chesapeake Bay. It is visible to all passing navy ships. The 47 crewmen were:
Tung Thanh Adams, Robert Wallace Backherms, Dwayne Collier Battle, Walter Scot Blakey, Pete Edward Bopp, Ramon Jarel Bradshaw, Philip Edward Buch, Eric Ellis Casey, John Peter Cramer, Milton Francis DeVaul, Jr., Leslie Allen Everhart, Jr., Gary John Fisk, Tyrone Dwayne Foley, Robert James Gedeon, III, Brian Wayne Gendron, John Leonard Goins, David L. Hanson, Ernest Edward Hanyecz, Clayton Michael Hartwig, Michael William Helton, Scott Alan Holt, Reginald L. Johnson, Jr., Brian Robert Jones, Nathaniel Clifford Jones, Jr., Michael Shannon Justice, Edward J. Kimble, Richard E. Lawrence, Richard John Lewis, Jose Luis Martinez, Jr., Todd Christopher McMullen, Todd Edward Miller, Robert Kenneth Morrison, Otis Levance Moses, Darin Andrew Ogden, Ricky Ronald Peterson, Matthew Ray Price, Harold Earl Romine, Jr., Geoffrey Scott Schelin, Heath Eugene Stillwagon, Todd Thomas Tatham, Jack Ernest Thompson, Stephen J. Welden, James Darrell White, Rodney Maurice White, Michael Robert Williams, John Rodney Young, Reginald Owen Ziegler.