During the late 1800s, the development of metal-hulled ships of large size, and the use of gyroscopes to even out the action of waves, allowed for the rapid development of the very large gunship, which soon became known as battleships. These were fiendishly expensive so only the largest and richest nations could afford to continue in the race to build such ships.
But at the same time, the new weight of armor slowed them and the huge guns needed to penetrate that armor fired at very slow rates. This allowed for the possibility of a small and fast ship that could attack the battleships en-mass, at a much lower cost. However two problems remained, a weapon that could attack such a ship was not small, nor was a small power source available to power such a ship.
Both of these problems were solved at about the same time. The introduction of the steam turbine (and later, the internal combustion engine resulted in a power source that could offer much higher output from a small source. The introduction of the torpedo provided a weapon that could cripple, and sink, any battleship.
The result was the torpedo boat, a small boat (perhaps 50 feet) with high speed, carrying a small number of torpedoes. They were inexpensive and could be purchased in some quantity, allowing for mass attacks on larger fleets. While some of them would undoubtedly be lost to the guns of the larger ships while they ran into firing range, their cost was so low that sinking even one battleship in return would be a victory.
The introduction of the torpedo boat resulted in a flurry of activity in the fleets around the world, as smaller and faster guns were added to existing ships to ward off the new threat, and an entirely new class of ships, the torpedo boat destroyer was invented to counter them.
The most famous of these torpedo boats, PT-109, commanded by future United States President John F. Kennedy, was one of the hundreds of members of the PT-103 class completed between 1942 and 1945 by Elco Naval Division of Electric Boat Company at Bayonne, New Jersey.
The Elco boats were the largest in size of the three types of PT boats built for United States Navy use during World War II. Wooden-hulled, 80 feet long with a 20-foot, 8-inch beam, the Elco PT boats had three 12-cylinder Packard gasoline engines generating a total of 4,500 horsepower for a designed speed of 41 knots. With accommodations for 3 officers and 14 men, the crew varied from 12 to 14. Its full-load displacement was 56 tons.
Early Elco boats had two 20mm guns, four .50-caliber machine guns, and two or four 21-inch torpedo tubes. Some of them carried depth charges or mine racks. Later boats mounted one 40mm gun and four torpedo launching racks. Many boats received ad-hoc refits at advanced bases, mounting such light guns as Army Air Forces 37mm aircraft guns and even Japanese 23mm guns. Some PTs later received rocket launchers.
Originally conceived as antiship weapons, PTs were publicly, but erroneously, credited with sinking Japanese warships during the early months after Pearl Harbor.
During the long Solomons campaign, they operated usefully at night and times of low visibility against Japanese barge traffic in the "Slot." Throughout World War II, PTs operated in the southern, western, and northern Pacific, as well as in the Mediterranean and the English Channel. Some served off Normandy during that invasion.
Though their primary mission continued to be seen as attack of surface ships and craft, PTs were also used effectively to lay mines and smoke screens, to rescue downed aviators, and to carry out intelligence or raider operations. Almost all surviving Elco PTs were disposed of shortly after V-J Day. Two PTs survive in WW II configuration on static dispaly--Elco boat, PT-617, and PT 796, A 78 foot Higgins Fall River, Massachusetts. These boats are owned by PT Boats, Inc., a WW II PT veterans organization headquartered in a suburb of Memphis, TN.
Although more 80-foot Elco boats were built than any other type of motor torpedo boat, other types were built by the U. S. The British-designed 70-foot Vosper boats which were built for Lend Lease fired 18-inch torpedoes. Since the U.S. produced the heavier and longer 21-inch torpedoes, the U.S. Navy wanted a larger PT boat. After experimentation, the first PT boat built in any quantity was the 77-foot type built by Elco. These boats were used early in World War II.
In 1943 in the Solomons, three of these 77-foot PT boats, PT-59, PT-60, and PT-61, were even converted into gunboats by stripping the boat of all original armament except for the two twin .50 caliber gun mounts, and then adding two 40mm guns and four more twin .50 caliber machine guns. LTJG John F. Kennedy was the first commanding officer of PT-59 after the conversion.
Although the Huckins Yacht Company of Jacksonville, Florida, built a few 78-foot boats of the PT-95 class, the 80-foot Elco boats and the 78-foot Higgins boats became the standard motor torpedo boats of World War II. The Higgins boats which were built by Higgins Industries in New Orleans, Louisiana, were 78-foot boats of the PT-71 class. The Higgins boats had the same beam, full load displacement, engine, generators, shaft horsepower, trial speed, armament, and crew accommodations as the 80-foot Elco boats.
Cultural Impact
The story of Motor Torpedo Boat Squadron 3 in the retreat from the Philippines early in World War 2 was documented in the book They Were Expendable by W.L. White, ISBN 1557509484, originally published in 1942 soon after the events depicted. Later, in 1945 John Ford made it into a notable war film starring John Wayne.
The JFK story is told in PT 109: John F. Kennedy in WWII by Robert J. Donovan, published in 1961. (ISBN 0071376437). "PT 109" was also a 1963 film starring Cliff Robertson. While he was president, JFK handed out PT 109 tieclasps to favored guests and associates.
The TV situation comedy, and later film, McHale's Navy was set in a PT boat squadron.