When the Confederate submarine H.L. Hunley was found, the bodies of the crew were still in their duty positions within the vessel, as if they’d been unaware or unable to do anything to save the situation. Sarah Knapton reports on what is now believed to have killed the crew almost instantaneously:
The mystery of how the crew of one of the world’s first submarines died has finally been solved – they accidentally killed themselves.
The H.L. Hunley sank on February 17 1864 after torpedoing the USS Housatonic outside Charleston Harbour, South Carolina, during American Civil War.
She was one of the first submarines ever to be used in conflict, and the first to sink a battleship [Housatonic was actually a sloop-of-war, not a battleship].
It was assumed the blast had ruptured the sub, drowning its occupants, but when the Hunley was raised in 2000, salvage experts were amazed to find the eight-man crew poised as if they had been caught completely unawares by the tragedy. All were still sitting in their posts and there was no evidence that they had attempted to flee the foundering vessel.
Now researchers at Duke University believe they have the answer. Three years of experiments on a mini-test sub have shown that the torpedo blast would have created a shockwave great enough to instantly rupture the blood vessels in the lungs and brains of the submariners.
“This is the characteristic trauma of blast victims, they call it ‘blast lung,'” Dr Rachel Lance.
“You have an instant fatality that leaves no marks on the skeletal remains. Unfortunately, the soft tissues that would show us what happened have decomposed in the past hundred years.”
The Hunley‘s torpedo was not a self-propelled bomb, but a copper keg of 135 pounds of gunpowder held ahead and slightly below the Hunley‘s bow on a 16-foot pole called a spar
The sub rammed this spar into the enemy ship’s hull and the bomb exploded. The furthest any of the crew was from the blast was about 42 feet. The shockwave of the blast travelled about 1500 meters per second in water, and 340 m/sec in air, the researchers calculate.