HL Hunley: Research examines what killed Civil War submarine crew
There was no major damage to the hull that can be definitively traced until one day the HL Hunley, a 40-foot-long Confederate submarine, sank to the ocean floor off Charleston, in South Carolina, February 17, 1864.
He sank the enemy ship with a 135-pound torpedo, which was filled with black powder and attached to a pole 16 feet from the ship’s hull. The study’s authors say the torpedo is the key, but many wondered how an explosion could have killed the entire crew without leaving a trace.
To answer this question, biomechanist Rachel Lance designed a model of the Hunley, one-sixth the length of the 40-foot-long submarine. The model, built by sculptor Tripp Jarvis of Durham, was dubbed the CSS Tiny.
“When she first talked about blasting I was a little worried,” said Pitt, 65, a sixth-generation family farmer, whose grandchildren are now eight generations.
Pitt recalled the wires that meandered through the lake and the charges that exploded below the surface, throwing water into the air like a large firecracker, he said. One of her grandchildren was able to push the button.
“There was a little geyser,” he said. “It was great to see.”
Pitt, a self-proclaimed history buff, had always been interested in the Civil War. He has ancestors who were in the North Carolina regiments, and at least one of them is buried in their family’s cemetery. The house he lives in was built in 1830, before the Hunley sank.
He carefully watched the Hunley reports on the History Channel and the National Geographic Channel.
“They were perfectly still in this submarine,” Pitt said. “I think people would like to know what happened to the crew. Everything about the story is intriguing.”
Without leaving a trace
Suspended inside the CSS Tiny was a small pressure gauge, which revealed how the submarine’s torpedo explosion could have killed the Hunley’s crew without leaving a lasting mark: the shock wave created by the explosion. .
The shock wave hit the Hunley’s hull, which was less than an inch thick, said Lance, lead author of the new study. The metal bent slightly but fast enough to transfer the shock wave inside the cabin.
This wave then passed through the cabin, hitting each of the eight crew members, passing through their bodies. But the real damage, Lance said, likely happened when the pressure wave hit their lungs.
“The problem is when it goes through (the tissues) and suddenly hits the air,” she said.
Shock waves, like sound waves, travel quickly in water and solids but not in air. The wave slows down when it hits the lung, Lance said, and “that energy has to go somewhere.”
The end result: The blood vessels in the lungs can rupture, which is called pulmonary hemorrhage.
It is possible to survive a shock wave from quite a distance away, according to Chiffon accounts. Testimonies from the night of the Hunley’s sinking claimed that there was a blue light coming from the ocean. Some have speculated that it was the Hunley crew reporting that they had completed their mission.
But Lance, who is working on a book about the Hunleys, said she had doubts about the inconsistencies in those testimonies.
“Any explosive that we saw on the ground… would definitely create a deadly wave,” Lance said.
“These types of injuries are not subtle,” she added. “The damage is immediate.
The watch had stopped at 8:23 a.m., around the time of the Hunley attack, historians say.
Navy researchers who have been examining the Hunley for more than a decade have declined to comment on Lance’s study as their own research into the crew’s deaths is underway.
But Lance, for her part, said she felt that part of the mystery had been solved.
“This project was originally intended to be a side project and then it got out of hand when we realized we could do it,” she said.