By Harriet McLeod
NORTH CHARLESTON, South Carolina (Reuters) - Confederate Civil War vessel H.L. Hunley, the world's first successful combat submarine when it sank a Union ship in 1864, was unveiled in full and unobstructed for the first time on Thursday, capping a decade of careful preservation.
"No one alive has ever seen the Hunley complete. We're going to see it today," said engineer John King as a crane at a Charleston conservation laboratory slowly lifted a massive steel truss covering the top of the submarine.
About 20 engineers and scientists applauded as they caught the first glimpse of the intact 42-foot-long narrow iron cylinder, which was raised from the ocean floor near Charleston more than a decade ago. The public will see the same view but in a water tank to keep it from rusting.
"It's like looking at the sub for the first time. It's like the end of a long night," said Paul Mardikian, senior conservator since 1999 of the project to raise, excavate and conserve the Hunley.
In the summer of 2000, an expedition led by adventurer Clive Cussler raised the Hunley and delivered it to the conservatory on Charleston's old Navy base, where it sat in a 90,000-gallon tank of fresh water to leech salt out of its iron hull.
On weekdays, scientists drain the tank and work on the sub. On weekends, tourists who before this week could only see an obstructed view of the vessel in the water tank, now will be able to see it unimpeded.
Considered the Confederacy's stealth weapon, the Hunley sank the Union warship Housatonic in winter 1864, and then disappeared with all eight Confederate sailors inside.
The narrow, top-secret "torpedo fish," built in Mobile, Alabama by Horace Hunley from cast iron and wrought iron with a hand-cranked propeller, arrived in Charleston in 1863 while the city was under siege by Union troops and ships.
In the ensuing few months, it sank twice after sea trial accidents, killing 13 crew members including Horace Hunley, who was steering.
"There are historical references that the bodies of one crew had to be cut into pieces to remove them from the submarine," Mardikian told Reuters. "There was forensic evidence when they found the bones (between 1993 and 2004 in a Confederate graveyard beneath a football stadium in Charleston) that that was true."
The Confederate Navy hauled the sub up twice, recovered the bodies of the crew, and planned a winter attack.
On the night of February 17, 1864, its captain and seven crew left Sullivan's Island near Charleston, and hand-powered the sub to the Union warship four miles offshore. From a metal spar on its bow, the Hunley planted a 135-pound torpedo in the hull of the ship, which burned and sank.
Some historians say that the submarine showed a mission-accomplished lantern signal from its hatch to troops back on shore before it disappeared.
Mardikian has the lantern, which archaeologists found in the submarine more than a century later, in his laboratory.
Scientists removed 10 tons of sediment from the submarine, along with the bones, skulls and even brain matter of the crew members, Mardikian told Reuters. They also found fabric and sailors' personal belongings.
Facial reconstructions were made of each member of the third and final crew. They are displayed along with other artifacts in a museum near the submarine. In a nearby vault is a bent gold coin that archaeologists also found in the submarine. It was carried by the sub's captain, Lieutenant George Dixon, for good luck after it stopped a bullet from entering his leg during the Battle of Shiloh in 1862.
"The submarine was a perfect time capsule of everything inside," said Ben Rennison, one of three maritime archaeologists on the project.
The Hunley Project is a partnership among the South Carolina Hunley Commission, Clemson University Restoration Institute, the Naval Historical Center and the nonprofit Friends of the Hunley. The nonprofit group raised and spent $22 million on the project through 2010, a spokeswoman told Reuters.
The next phase of the project will be to remove corrosion on the iron hull and reveal the submarine's skin, preserve it with chemicals, and eventually display it in open air, Mardikian said.
Scientists have found the vessel to be a more sophisticated feat of engineering than historians had thought, said Michael Drews, director of Clemson's Warren Lasch Conservation Center.
"It has the ballast tanks fore and aft, the dive planes were counterbalanced, the propeller was shrouded," Drews said. "It's just got all of the elements that the modern submarines have, updated."
There were previous submarines, Drews said, but the Hunley, designed to sail in the open ocean and built for warfare, was cutting-edge technology at the time.
"Dixon's mission was to attack and sink an enemy ship and he did," Drews said. "At that particular time, the mindset of naval warfare was, basically, big ships sink little ships. Little ships do not sink big ships. And the Hunley turned that upside down."
(Editing by Greg McCune)