She was the first combat submarine to sink a warship (USS Housatonic), although Hunley was not completely submerged and, following her attack, was lost along with her crew before she could return to base.

She was named for her inventor, Horace Lawson Hunley, shortly after she was taken into government service under the control of the Confederate States Army at Charleston, South Carolina.

She sank again on 15 October 1863, killing all eight of her second crew, including Horace Lawson Hunley himself, who was aboard at the time, even though he was not a member of the Confederate military.

On 17 February 1864, Hunley attacked and sank the 1,240-ton United States Navy[2] screw sloop-of-war Housatonic, which had been on Union blockade-duty in Charleston's outer harbor.

Finally located in 1995, Hunley was raised in 2000 and is on display in North Charleston, South Carolina, at the Warren Lasch Conservation Center on the Cooper River.

During the course of the battle the weaponry changed and such things as: mines, accurate guns, more deadly bullets, torpedoes, and "ironclad" ships became a new standard.

Likely having within them an incessant loyalty to the Confederate states as well as understanding the financial gains that would come from sinking enemy ships,[8] Hunley, McClintock, and Baxter Watson first built Pioneer.

[7] McClintock noted the significance that a boat capable of moving in any direction at any depth could be made, but ultimately decided that such a vessel could be improved.

Legend held that Hunley was made from a cast-off steam boiler—perhaps because a cutaway drawing by William Alexander, who had seen her, showed a short and stubby machine.

If 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.

However, archaeologists working on Hunley discovered evidence, including a spool of copper wire and components of a battery, that it may have been electrically detonated.

In the configuration used in the attack on Housatonic, it appears Hunley's torpedo had no barbs and was designed to explode on contact as it was pushed against an enemy vessel at close range.

A drawing of the iron pipe spar, confirming her "David" type configuration, was published in early histories of submarine warfare.

The target was United States Navy ship, USS Housatonic, a 1,240-long-ton (1,260 t)[2] wooden-hulled steam-powered screw sloop-of-war with 12 large cannons, which was stationed at the entrance to Charleston, about 5 miles (8.0 kilometres) offshore.

[21] Pyrotechnic "blue light" could be seen easily over the four-mile (6 km) distance between Battery Marshall and the site of Hunley's attack on Housatonic.

At one point, the finders of Hunley suggested she was unintentionally rammed by USS Canandaigua when that warship was going to rescue the crew of Housatonic, but no such damage was found when she was raised from the bottom of the harbor.

Instead, all evidence and analysis eventually pointed to the instantaneous death of Hunley's entire crew at the moment of the spar torpedo's contact with the hull of Housatonic.

Their research, which included scaled experiments with live black powder bombs, provided data indicating the crew was likely killed by the explosion of their own torpedo, which could have caused immediate pulmonary blast trauma.

The Duke team's experiments and results were published August 2017 in the peer-reviewed journal PLoS One[14] and eventually became the subject of the book In the Waves: My Quest to Solve the Mystery of a Civil War Submarine.

Underwater archaeologist E. Lee Spence, president, Sea Research Society, reportedly discovered Hunley in 1970,[29][30] and has a collection of evidence[31] claiming to validate this, including a 1980 Civil Admiralty Case.

[34] Spence's book Treasures of the Confederate Coast, which had a chapter on his discovery of Hunley and included a map complete with an "X" showing the wreck's location, was published in January 1995.

[35] Diver Ralph Wilbanks located the wreck in April 1995 while leading a NUMA dive team originally organized by archaeologist Mark Newell and funded by novelist Clive Cussler,[36] who announced the find as a new discovery[37] and first claimed that the location was in about 18 ft (5.5 m) of water over one mile (1.6 km) inshore of Housatonic, but later admitted to a reporter that that was false.

The submarine was resting on her starboard side, at about a 45-degree angle, and was covered in a 1⁄4 to 3⁄4 inch (0.64 to 1.91 cm) thick encrustation of rust bonded with sand and seashell particles.

[49][50] She was raised from the open waters of the Atlantic Ocean, just over 3.5 nautical miles (6.5 km) from Sullivan's Island outside the entrance to Charleston Harbor.

[51][52] On 8 August 2000, at 08:37, the sub broke the surface for the first time in more than 136 years, greeted by a cheering crowd on shore and in surrounding watercraft, including author Clive Cussler.

This program was based on a section ("Part 6") in Clive Cussler's 1996 non-fiction book of the same name (which was accepted by the Board of Governors of the Maritime College of the State University of New York in lieu of his Ph.D.

[53] In 2001, Clive Cussler filed a lawsuit against E. Lee Spence for unfair competition, injurious falsehood, civil conspiracy, and defamation.

The crew was composed of Lieutenant George E. Dixon (Commander) (of Alabama or Ohio), Frank Collins (of Virginia), Joseph F. Ridgaway (of Maryland), James A. Wicks (North Carolina native living in Florida), Arnold Becker (of Germany), Corporal Johan Frederik Carlsen (of Denmark), C. Lumpkin (probably of the British Isles), and Augustus Miller (probably a former member of the German Artillery).

By examining Civil War records and conducting DNA testing with possible relatives, forensic genealogist Linda Abrams identified the remains of Dixon and the three other Americans: Frank G. Collins of Fredericksburg, Va., Joseph Ridgaway, and James A.

Another surprise occurred in 2002, when lead researcher Maria Jacobsen,[65][66] examining the area close to Lieutenant Dixon, found a misshapen $20 gold piece, minted in 1860, with the inscription "Shiloh April 6, 1862, My life Preserver G. E. D." on a sanded-smooth area of the coin's reverse side, and a forensic anthropologist found a healed injury to Lt. Dixon's hip bone.