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This U.S. Navy Battleship's Blew Up (Twice)

September 21, 2019 Topic: Security Blog Brand: The Buzz Tags: U.S. NavyNaval AccidentMilitaryWarCold War

This U.S. Navy Battleship's Blew Up (Twice)

Despite her forty years of service, Mississippi was bound to tragedy, experiencing two major accidents in the same turret, in the same gun, twenty years apart.

The USS Mississippi is home to one of the most intriguing naval coincidences of all time. Built while America was a neutral party in World War I, Mississippi sailed into the atomic age and later served as a massive test platform for surface-to-air missiles. Despite her forty years of service, Mississippi was bound to tragedy, experiencing two major accidents in the same turret, in the same gun, twenty years apart.

USS Mississippi (BB-41) was the second of three ships of the New Mexico-class battleships. Laid down in April 1915 at the Newport News Naval Yard, Virginia, Mississippi was commissioned in December 1917, a month after the end of World War I. The New Mexico class was the fourth of six distinct battleship classes laid down the 1910s, as the Navy rushed to fortify the Atlantic against tensions—and then outright war—in Europe.

Mississippi was a heavily armed battleship by the standards of the day. She was armed with a main battery of twelve 14-inch/50 caliber guns mounted in four turrets of three guns each, with each gun mounted in a separate sleeve. The main battery was distributed two turrets forward and two aft. She also featured twelve 5-inch/51 caliber guns, eight 3-inch anti-aircraft guns and two submerged 21-inch torpedo tubes.

As a battleship, the Mississippi was heavily armored to slug it out with enemy ships. The New Mexico-class ships had 13.5 inches of steel armor at the belt, and her turrets were protected with nine to eighteen inches of armor plating. The deck was armored to 3.5 inches and the conning tower to sixteen inches.

The mighty warship was 624 feet long with a beam of 97.5 feet, and displaced 33,000 tons fully loaded. She was powered by nine Babcock and Wilcox boilers and her four screws were driven by four Curtis turbines producing a maximum 32,000 horsepower. At roughly one horsepower per ton, she was not terribly fast, with a top speed of just twenty-one knots.

On June 12, 1924, Mississippi found herself off the coast of California conducting gun trials. The 14-inch/50 caliber gun was plagued with technical issues, a major problem considering it was the primary armament on the majority of serving U.S. Navy battleships. On the eighth salvo, turret two, gun two suffered a rare “flare back.” The four powder bags inserted into the breech, totaling 470 pounds of explosive powder, caught fire and ignited other bags waiting to be loaded. Forty-eight sailors were killed, and only one of the sailors manning the turret survived.

Based on the survivor’s account, the Navy believed that a fire or burning debris was present in the gun barrel and ignited the powder bags. Although each barrel was blasted between firings with pressurized air to evacuate debris, the middle barrel of each turret received a lower pressure burst than the left and right barrels. This could have led to dangerous debris remaining in the breech when the gun crew assumed it was safe to load.

A bizarre accident occurred afterward while the Mississippi was anchored in San Pedro Bay. The hand of a dead crewman in the number two turret accidentally hit the firing switch for the port gun, firing it. The shell flew harmlessly out to sea.

Nearly twenty years—and a major refit later—the USS Mississippi went to war in the Pacific. In 1943, the big battleship was off the coast of Makin Island, providing naval gunfire support to a landing force preparing to secure the island. After an extensive preliminary bombardment, the Marine assault force headed towards the beach and Mississippi and the other ships increased their rate of fire.

Suddenly, in the midst of the barrage, smoke and gas erupted from the rangefinders on either side of the number two turret. Incredibly it had happened again: in their haste to lay down a rain of shells on the Japanese, the gunners of number two turret had apparently experienced yet another flare back. Debris from firing the big guns had again ignited powder bags, causing the same accident and the same damage. Forty-two sailors were killed and another sixteen wounded. The battleship’s three remaining turrets continued firing until the naval support phase of the invasion had ended.

After the war, Mississippi was effectively defanged, with three of her four main battery turrets removed. She was redesignated AG-128 and equipped with a number of radars and prototype air defense missile systems. Mississippi was instrumental in the testing and eventual fielding of the Convair RIM-2 Terrier, the U.S. Navy’s first surface-to-air missile.

The old warship was decommissioned in 1956, sold for scrap. The aging battlewagon had served longer than most ships at the time, but it had also experienced two rare tragedies, in the same place, under similar circumstances. Today her name lives on in the Virginia class nuclear-powered attack submarine USS Mississippi (SSN-782).

Kyle Mizokami is a defense and national security writer based in San Francisco who has appeared in the Diplomat, Foreign Policy, War is Boring and the Daily Beast. In 2009 he cofounded the defense and security blog Japan Security Watch. You can follow him on Twitter: @KyleMizokami.

Image: Wikipedia.