At approximately 8:45 PM, just outside of Charleston Harbor, near Sullivan’s Island, Dixon spotted the USS Housatonic waiting for blockade runners and Hunley began closing in for the kill. The Union ship’s Officer of the Deck noticed the approaching vessel and called for reversing the engines to maneuver,but it was too late, the torpedo containing 70 – 90 pounds of explosives had penetrated the her hull near the after magazine and exploded. USS Housatonic became the first vessel to fall victim to an attack by a submarine.
From its earliest beginnings, the world’s militaries have sought ways to explore and exploit the oceans’ surface and depths to gain advantage over their adversaries. These included improving on designs for people to go under water for prolonged period. The well-known sketches of Leonardo DaVinci included such ideas. During the American Revolution, David Bushnell created a submersible named Turtle, attempting to sink a British Man of War by attaching an explosive charge to its hull; an attempt that failed. But it was Horace Hunley and his associates who produced the first militarily successful submersible during the American Civil War. While other designers and builders, such as John Holland and Simon Lake would improve upon the designs and later builders would perfect them, Hunley, remarkably, was the first the have a design sufficient to sink a major man-of-war and insofar as it is possible to ascertain, escape enemy retaliation.
The project to design and build a submersible boat capable of attacking a surface ship started in February 1862 when a group of New Orleans businessmen became inspired by the concept of a combat submarine presented to them by James McClintock and Horace L. Hunley.
Using their own money as well as monies from investors, McClintock and Hunley began construction of the submersible in New Orleans. As Southern patriots, they wanted to help the Confederacy break the blockade of southern ports by sinking or capturing Union blockaders and, as businessmen, earn a profit doing so. Thus it came about that the first operational attack submarine would be a “privateer”.
McLintock and Hunley’s first attempt resulted in a craft they called Pioneer. After several successful trial runs in Lake Pontchartrain, Pioneer showed that she was capable of diving and moving underwater, however several significant defects made her unsuitable for the mission. As Union forces were moving to capture New Orleans, Pioneer was scuttled in a deep cut of the lake to keep her from being taken by the enemy. The project to build a submarine moved to Mobile, Alabama. This area was relatively safe from Union forces in part due to the natural protection afforded by Mobile Bay. At Mobile, they obtained the services of a machine shop owned by Thomas Park and Thomas Lyons. Fortune was in their favor. Two of the men working in the Park and Lyons shop were William Alexander a master machinist and George Dixon, a recently promoted Lieutenant in the Confederate Army whose mechanical talent was noted by his superiors who sent him to work at the shop building new weapons.
The second boat had improved features over the first since Mclintock had noted every defect of the Pioneer and made corrections to the design to overcome the defects. The second boat named American Diver made several trial runs in Mobile Bay that encouraged the builders to plan an attack on Union ships off Sand Island, outside the Bay.
To expedite the trip to their target, American Diver was to be towed to a point near Sand Island and then submerge for the attack. The kill method was an explosive charge on a rope trailed behind them on the surface. The idea was to pass under a Union ship thus pulling the explosive charge against the Union ship.
Unfortunately, as Diver was being towed to a position closer to the target, it suddenly submerged and sunk. Thus, the second attempt to build a successful submarine had failed. But McLintock and Hunley did not give up.
As the story unfolds, the project persisted to build a third and more successful model called Fishing Boat or Porpoise which incorporated sleek lines and improved engineering in its design. This was the boat destined to add a new and terrifying chapter to the history of naval warfare. The boat was renamed H. L. Hunley after the designer-builder died in the second sinking of this boat in Charleston Harbor.
In February 1864, the Union naval blockade was strangling the Confederacy and, as a major port, Charleston, South Carolina, was a primary point of embarkation and debarkation for the Southern blockade runners. Food and other commodities including weapons and ammunition were in short supply.
Among the blockading ships was the USS Housatonic, a steam and sail driven man-of-war, launched in 1861, with a crew of 160. With a top speed of 9 knots, she weighed 1,240 tons with a length of 207 feet, a beam of 38 feet and a draft of 8 feet 7 inches. Housatonic’s armament consisted of 1 100-pounder Parrott rifle, 3 30-pounder Parrott rifles, 1 11" Dahlgren smoothbore, 2 32-pounders, 2 24-pounder howitzers, 1 12-pounder howitzer, 1 12-pounder rifle.