USS Iowa Turret Explosion
At 09:53, about 81 seconds after Moosally's order to load and 20 seconds after the left gun had reported loaded and ready, Turret Two's center gun exploded.
A fireball between 2,500 and 3,000 °F (1,400 and 1,600 °C) and traveling at 2,000 feet per second (610 m/s) with a pressure of 4,000 pounds-force per square inch (28 MPa) blew out from the center gun's open breech. The explosion caved in the door between the center gun room and the turret officer's booth and buckled the bulkheads separating the center gun room from the left and right gun rooms. The fireball spread through all three gun rooms and through much of the lower levels of the turret. The resulting fire released toxic gases, including cyanide gas from burning polyurethane foam, which filled the turret. Shortly after the initial explosion, the heat and fire ignited 2,000 pounds (910 kg) of powder bags in the powder-handling area of the turret. Nine minutes later, another explosion, most likely caused by a buildup of carbon monoxide gas, occurred. All 47 crewmen inside the turret were killed. The turret contained most of the force of the explosion. Twelve crewmen working in or near the turret's powder magazine and annular spaces, located adjacent to the bottom of the turret, were able to escape without serious injury.
The Navy today reopened its investigation into the explosion on the battleship Iowa after an ''unexplained ignition'' of gunpowder bags in a test earlier in the day raised the possibility that the Iowa blast was accidental.
Navy Secretary Lawrence Garrett 3d also ordered the Navy to suspend the firing of 16-inch guns on its battleships. The Iowa explosion occurred in the turret of one of her 16-inch guns as the crew was loading the gun.
The Navy had previously rejected suggestions that the explosion was accidental, asserting that Clayton M. Hartwig, a gunner's mate second class, probably set off the blast in an act of suicide. That theory has been criticized by experts outside the Navy, and even some Navy officials say privately that they are not persuaded by the services's official explanation.
Ten years ago this summer, the families of 47 Navy sailors were grieving over the loss of their loved ones after a gun turret exploded on the battleship USS Iowa as it steamed through the Caribbean, off Puerto Rico, on April 19, 1989.
Now they have reason to grieve again, for the Navy has effectively suppressed the results of the lone independent investigation of the accident. That investigation lays blame for the deaths squarely where it belongs: on the Navy itself.