Saturday, June 25, 2011

World's First Combat Sub CSA Hunley Upright For First Time In Over A Century

Drawing of the H. L. Hunley. Based on a Photograph taken in 1863 by George S. Cook
File:Css hunley on pier.jpg
Image: Wikipedia

The Hunley may not be ready to set sail again, but after today, she almost looks like she could.

Scientists finished their work of carefully rotating the Hunley to an upright position, completing a major milestone in the effort to save the world’s first successful combat submarine. And it was a moment 147 years in the making.


H.L. Hunley was a submarine of the Confederate States of America that played a small part in the American Civil War, but a large role in the history of naval warfare. The Hunley demonstrated both the advantages and the dangers of undersea warfare. It was the first combat submarine to sink an enemy warship, although the Hunley was not completely submerged and was lost at some point following her successful attack.  

The Confederacy lost 21 crewmen in three sinkings of the Hunley during her short career. The submarine was named for her inventor, Horace Lawson Hunley, shortly after it was taken into service under the control of the Confederate Army at Charleston, South Carolina.

View of the port bow. Archaeologist inspects the water spray system attached to the recovery truss.
Credit: Friends of the Hunley

H. L. Hunley, nearly 40 feet (12 m) long, was built at Mobile, Alabama, and launched in July 1863. It was then shipped by rail on August 12, 1863 to Charleston, South Carolina. Hunley (then called Fish Boat) sank on August 29, 1863, during a training exercise, killing five members of her crew. It sank again on October 15, 1863, killing all eight of her second crew, including H. L. Hunley himself, who was aboard at the time, even though he was not enlisted in the Confederate armed forces. Both times the Hunley was raised and returned to service. On February 17, 1864, Hunley attacked and sank the 1240-short ton (1124 metric tons) screw sloop USS Housatonic on Union blockade duty in Charleston's outer harbor. Soon after, Hunley sank for unknown reasons, killing all eight of her third crew. This time, the innovative ship was lost. 

Inboard profile and plan drawings, after sketches byW.A. Alexander (1863)
File:Hunley-1.jpg
Image: Wikipedia

The Hunley has rested on her side at a 45-degree angle since the she was lost in 1864. The submarine was lifted from the ocean floor in that exact same position in 2000 and has remained on her side, until now. The historic shift in her delineation has left the Hunley upright on her keel as she was originally designed to be and in position to undergo her final mission: a complete preservation treatment. 

Next, scientists will remove the straps and overhead truss that have held the Hunley since her recovery, exposing a new side of the vessel that has not been fully seen since the crew entered it over a century ago. This won’t be done for a few weeks, however, so scientists can have the additional support of the slings available while they ensure the submarine is completely stable in the new position.

Hunley Commission Chairman Senator Glenn McConnell said he is eager to have access to this new area of the submarine, hoping new clues may be uncovered that will provide insight into the mystery of the crew’s demise. “This is tremendous day for the project. Not only will the public soon have an unobstructed view, we will too. We may the find the crucial evidence we’ve been searching for in this newly exposed area” McConnell said.

The Hunley is a fragile 19th century artifact, making safely moving the approximate 7-ton, 40-foot submarine a challenging engineering feat and risky endeavor. The team spent two years planning the rotation and tested various simulations in advance on a 3D model.

The process to rotate the sub was at times slow and tedious and others nerve-racking. The painstaking project took three days, with scientists rotating the submarine mere millimeters at a time. After each incremental move, a series of computer monitors were checked to ensure even weight distribution with no major stresses on the submarine. 

Two technical issues added hours, and a little tension, to the project. At one point, the bow started to dip too much toward the ground and scientists had to make modifications to get the submarine level again. They had anticipated the potential of this occurring though had hoped it would not affect the rotation.
Also, a laser monitoring system – critical to detecting any potential warping or damage that scientists were desperately trying to avoid – had to be adjusted one morning, causing a delay of a few hours for rotation work to start.

“It’s fair to say we are all breathing a collective sigh of relief now that the rotation is over. The laser never strayed more than a millimeter out of its target. Aside from minor technical issues, the rotation went according to plan with the sub remaining completely safe and intact,” Mike Drews, Director of Clemson University’s Warren Lasch Conservation Center, said.

This project would not have been possible without the generous support and expertise of J. A. King & Co., Parker Rigging, Inc., Detyens Shipyard and the entire Hunley team who worked tirelessly in support of this effort. 

The Hunley Project
On the evening of February 17, 1864, the H. L. Hunley became the world’s first successful combat submarine by sinking the USS Housatonic. After signaling to shore that the mission had been accomplished, the submarine and her crew of eight mysteriously vanished. 

Lost at sea for over a century, the Hunley was located in 1995 by Clive Cussler’s National Underwater and Marine Agency (NUMA). The innovative hand-cranked vessel was raised in 2000 and delivered to the Warren Lasch Conservation Center, where an international team of scientists are at work to conserve the submarine for future generations and piece together clues to solve the mystery of her disappearance. The Hunley Project is conducted through a partnership with the Clemson University Restoration Institute, South Carolina Hunley Commission, Naval Historical Center, and Friends of the Hunley.


Source: 
Kellen Correia

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