Originally Posted by L-Pink

By loading 5 powder bags instead of anticipated 6 I'm guessing the void allowed more force? Plus the compromised state of contaminated powder.


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Originally Posted by Lichen

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. These men were protected by blast doors which separate the magazine spaces from the rest of the turret.