CSS Hunley, a general history and description

Submarine | Article - Posting | Civil War (USA) | USA

CSS H. L. Hunley was a submarine of the Confederate States Navy that demonstrated both the advantages and the dangers of undersea warfare. Hunley was the first submarine to sink a warship, though the sub was also sunk in the engagement.

Hunley and two earlier submarines were privately developed and paid for by Horace Lawson Hunley, James McClintock and Baxter Watson.

Predecessors to Hunley

Hunley, McClintock and Watson first built a small submarine named Pioneer at New Orleans, Louisiana. Pioneer was tested in February 1862 in the Mississippi River, and was later towed to Lake Pontchartrain for additional trials. But the Union advance towards New Orleans caused the men to abandon development and scuttle Pioneer the following month.

The three inventors moved to Mobile, Alabama, and teamed up with Thomas Park and Thomas Lyons, owners of the Park & Lyons machine shop. They soon began development of a second submarine, American Diver. Their efforts were supported by the Confederate States Army; Lieutenant William Alexander of the 21st Alabama Volunteer Regiment was assigned to duty at Park & Lyons. The men experimented with electromagnetic and steam propulsion for the new submarine before falling back on a simpler hand-cranked propulsion system. American Diver was ready for harbor trials by January 1863, but proved to be too slow to be practical. One attempted attack on the Union blockade was made in February 1863, but was unsuccessful. American Diver sank in the mouth of Mobile Bay during a storm later the same month, and was not recovered.

Construction and testing of Hunley

Construction of Hunley began soon after the loss of American Diver. Hunley, which at this stage was variously referred to as the "fish boat", the "fish torpedo boat" or the "porpoise", was fashioned from a cylindrical iron steam boiler, which was deepened and also lengthened through the addition of tapered ends. The Hunley was designed to be hand powered by a crew of eight: seven to turn the hand-cranked propeller and one to steer and direct the boat. As a true submarine, each end was equipped with ballast tanks that could be flooded by valves or pumped dry by hand pumps. Extra ballast was added through the use of iron weights bolted to the underside of the hull. In the event the submarine needed additional buoyancy to rise in an emergency, the iron weight could be removed by unscrewing the heads of the bolts from inside the vessel.

Cutaway drawing of CSS H. L. Hunley by William Alexander

Hunley was equipped with two watertight hatches, one fore and one aft, atop two conning towers with small portholes. The hatches were very small, measuring 14 by 15¾ inches (356 by 400 mm), making entrance to and egress from the hull very difficult.

Hunley was ready for a demonstration by July 1863. With Confederate Admiral Franklin Buchanan looking on, Hunley successfully attacked a coal flatboat in Mobile Bay. Following this demonstration of Hunley's attack capabilities, the submarine was shipped to Charleston, South Carolina, by rail, arriving August 12, 1863.

The Confederate military seized the vessel from its private builders and owners shortly after its arrival in Charleson and turned it over to the Confederate Navy. Hunley would operate as a Confederate Navy vessel from this point forward, although Horace Hunley and his partners remained involved in the submarine's further testing and operation.

Confederate Navy Lieutenant John A. Payne of CSS Chicora volunteered to be Hunley's skipper, and a volunteer crew of seven men from Chicora and CSS Palmetto State was assembled to operate the submarine. On August 29, 1863, Hunley's new crew was preparing to make a test dive to learn the operation of the submarine when Lieutenant Payne accidentally stepped on the lever controlling the sub's diving planes. This caused Hunley to dive with hatches still open, flooding and sinking the vessel. Payne and two other men escaped; the remaining five crewmen drowned.

On October 15, 1863 the Hunley failed to surface during a trial dive, killing its inventor Horace Lawson Hunley and seven other crewmen. In both cases, the Confederate Navy salvaged the vessel and returned it to service.

Attack on USS Housatonic

Although it had never launched a successful attack, on February 17, 1864, the Confederate submarine made a night attack on the USS Housatonic. Housatonic, an 1800-ton steam powered sloop-of-war with 12 large cannon, was at the entrance to Charleston, South Carolina harbor, about 4 miles out to sea. In an effort to break the naval blockade of the city, Lieutenant George A. Dixon and a crew of seven volunteers rammed the Hunley into the Housatonic with 90 pounds (41 kg) of explosive powder attached to a 22-foot long spar on its bow. The explosives were embedded in the sloop's wooden side and were detonated by a rope/trigger, as the Hunley backed away. The resulting explosion sent the Housatonic with five crew members to the bottom of Charleston Harbor, in five minutes. The Hunley also sank, moments after signalling shore, possibly because of the blast, although this is not certain. The entire crew died, but the H.L. Hunley earned a place in the history of undersea warfare as the first submarine to sink a ship in wartime.

The Wreck

CSS H. L. Hunley, suspended from a crane during its recovery from Charleston Harbor, August 8, 2000. (Photograph from the U.S. Naval Historical Center.)

The search for the Hunley ended in 1995, 131 years later, when best-selling author Clive Cussler, and his team from the National Underwater and Marine Agency (NUMA) discovered the submarine after a 14-year search. At the time of discovery, Cussler and NUMA were conducting this research in partnership with the South Carolina Institute of Anthropology and Archaeology (SCIAA). The team realized that they had found the Hunley after exposing the forward hatch and the ventilator box (the air box for the attachment of a snorkel). The submarine rested on its starboard side at about a 45-degree angle and was covered in a 1/4 to 3/4-inch encrustation of ferrous oxide bonded with sand and seashell particles. Archaeologists exposed a little more on the port side and found the bow dive plane on that side. More probing revealed an approximate length of 40 feet with all of the vessel preserved under the sediment.

Archaeological investigation and excavation culminated with the raising of the Hunley from its watery grave on August 8, 2000. A large team of professionals from the Naval Historical Center's Underwater Archaeology Branch, National Park Service, the South Carolina Institute of Archaeology and Anthropology, and various other individuals investigated the vessel, measuring and documenting it prior to removal. Once the on site investigation was complete, harnesses were slipped underneath the sub one by one and attached to a truss designed by Oceaneering, Inc. After the last harness had been secured, the crane from the recovery barge Karlissa B began hoisting the submarine from the mire of the harbor entrance. On August 8, 2000 at 8:37 a.m. the sub broke the surface for the first time in over 136 years, where it was greeted by a cheering crowd lining the shore and in hundreds of nearby watercraft. Once safely on its transporting barge, the Hunley finally completed its last voyage back to Charleston. The removal operation reached its successful conclusion when the submarine was secured inside the Warren Lasch Conservation Center, at the former Charleston Navy Yard in a specially designed tank of freshwater to await conservation.