The world's first successful combat submarine, H.L. Hunley, was set upright in late June, only the second time the Confederate submarine has been moved since she mysteriously vanished
in February 1864 after sinking the Union
warship USS Housatonic. In 1995, the National Underwater Marine Agency found Hunley resting on the seabed at a 45-degree angle. In 2000,
a team of conservators, archaeologists and
engineers raised the sub and carefully placed
her in a conservation tank in Charleston, S.C., where she continued to rest at the same 45-degree angle on the slings used to raise her.
The team spent two years planning the rotation to an upright position, using a 3-D model to simulate the move. The operation began with two cranes raising the roughly 10-ton, 40-foot submarine three feet above the bottom of the drained conservation tank. With sensors rigged to detect any uneven weight distribution or major structural stress, workers then adjusted the slings to rotate Hunley a few millimeters
at a time over three days, until her keel was
in position to rest on adjustable support blocks placed underneath it.
The Hunley team will now begin comprehensive conservation of the sub, including removing the layer of shell, sediment and rust that has covered her iron structure for nearly a century and a half.
|(Top left) Staff members at Clemson University's Warren Lasch Conservation Center rotate the Civil War submarine H.L. Hunley by releasing tension on chain hoists. (Top, right) Conservator Chris Watters operates one of the chain hoists used to slowly rotate the Hunley submarine into an upright position. (Bottom) Mike Drews, lab manager at Clemson University's Warren Lasch Conservation Center, inspects Hunley after the successful rotation of the Civil War submarine. (Photos by Friends of the Hunley / Cramer Gallimore)