High speed transport
Encyclopedia
High Speed Transports were converted destroyer
s and destroyer escort
s used to support amphibious operations
in World War II
and afterward. They received the US Hull classification symbol
APD; "AP" for transport and "D" for destroyer.
APDs were intended to deliver small units such as Marine Raiders
, Underwater Demolition Team
s and United States Army Rangers onto hostile shores. They could carry up to a company
size unit. They also provided gunfire support
as needed.
, 17 Wickes class
, and 14 Clemson class
"flush-deck" destroyers built during and after World War I
. Some of these had been previously converted to aircraft tenders or other uses.
In the conversion, the two forward boilers (out of four) were removed with their smokestacks (reducing speed to 25 knots). Accommodation for 200 troops was installed in the former engine spaces. The original armament of four 4" guns, one 3" AA gun
, and twelve torpedo tubes was replaced with three modern 3" AA guns, one 40mm AA gun
, and five 20mm AA guns
. Two depth charge
racks and six anti-submarine mortars
were carried. In place of the torpedo mounts, four davit mounted LCPL
s (landing craft
) were shipped.
destroyer escort
s (DE)s built in 1943-1945. These converted vessels were known as the Charles Lawrence class.
In the conversion, the superstructure was expanded to provide accommodation for 162 troops. The original gun armament of three 3" AA guns and and six 20mm AA guns
was replaced with one 5" DP gun and six 40mm AA guns
. The Charles Lawrence class retained the original three torpedo tubes, and carried two depth charge racks and eight ASW mortars.
destroyer escort
s (DE)s built in 1943-1945. All but one of these was converted while under construction. These converted vessels were known as the Crosley class.
This conversion was the same as the Buckley class, except that the original armament had two 5" DP guns instead of three 3" guns; the after 5" gun was removed.
The exigencies of the Guadalcanal Campaign
, where neither side enjoyed the overwhelming local naval and air supremacy which insured victory in every other amphibious operation
of the war, necessitated an increase in the number of high-speed transports, hybrid warships which combined the functions of transports and destroyers. The concept of the high-speed transport embodied sufficient armament for the ship to defend herself against smaller warships and to support the troops she carried with sufficient speed to enable her to outrun more heavily armed ships.
APDs performed much arduous service. They transported troops to beachheads, served as escorts for transports and supply vessels, conducted anti-submarine
patrols and survey duties, operated with Underwater Demolition Team
s and commando
units, performed messenger and transport duties, conveyed passengers and mail to and from forward units, and were involved in mine sweeping operations. They were attacked by submarines, surface ships and aircraft (including kamikaze
s), and many were damaged or sunk.
Some of the Charles Lawrence class and Crosley class APDs saw service in the Korean War
and Vietnam War
.
One Charles Lawrence class APD was lost during World War II. 14 were transferred to foreign navies in the 1960s. One was sold for commercial use as a floating power station. 26 were scrapped. On 1 January 1969, the remaining three were reclassified as "Fast Amphibious Transports" (LPR).
No Crosley class APD was lost during World War II. 18 were transferred to foreign navies. One was lost in a collision in 1966. Eight were sold as floating power stations. 18 were scrapped. In 1969, the remaining eight were reclassified as "Fast Amphibious Transports" (LPR).
Destroyer
In naval terminology, a destroyer is a fast and maneuverable yet long-endurance warship intended to escort larger vessels in a fleet, convoy or battle group and defend them against smaller, powerful, short-range attackers. Destroyers, originally called torpedo-boat destroyers in 1892, evolved from...
s and destroyer escort
Destroyer escort
A destroyer escort is the classification for a smaller, lightly armed warship designed to be used to escort convoys of merchant marine ships, primarily of the United States Merchant Marine in World War II. It is employed primarily for anti-submarine warfare, but also provides some protection...
s used to support amphibious operations
Amphibious warfare
Amphibious warfare is the use of naval firepower, logistics and strategy to project military power ashore. In previous eras it stood as the primary method of delivering troops to non-contiguous enemy-held terrain...
in World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
and afterward. They received the US Hull classification symbol
Hull classification symbol
The United States Navy, United States Coast Guard, and United States National Oceanic and Atmospheric Administration use hull classification symbols to identify their ship types and each individual ship within each type...
APD; "AP" for transport and "D" for destroyer.
APDs were intended to deliver small units such as Marine Raiders
Marine Raiders
The Marine Raiders were elite units established by the United States Marine Corps during World War II to conduct amphibious light infantry warfare, particularly in landing in rubber boats and operating behind the lines...
, Underwater Demolition Team
Underwater Demolition Team
The Underwater Demolition Teams were an elite special-purpose force established by the United States Navy during World War II. They also served during the Korean War and the Vietnam War...
s and United States Army Rangers onto hostile shores. They could carry up to a company
Company (military unit)
A company is a military unit, typically consisting of 80–225 soldiers and usually commanded by a Captain, Major or Commandant. Most companies are formed of three to five platoons although the exact number may vary by country, unit type, and structure...
size unit. They also provided gunfire support
Naval gunfire support
Naval gunfire support is the use of naval artillery to provide fire support for amphibious assault and other troops operating within their range. NGFS is one of a number of disciplines encompassed by the term Naval Fires...
as needed.
"Flush-deck" conversions
The first group of APDs (APD-1 through APD-36) were converted from one Caldwell classCaldwell class destroyer
The Caldwell class of destroyers served in the United States Navy near the end of World War I.Built in 1917 and 1918, the 6 ships of the Caldwell class were flush-decked to remove the fo'c'sle break weakness of the preceding Tucker class. The forward sheer of the Caldwell class was improved to...
, 17 Wickes class
Wickes class destroyer
The Wickes-class destroyers were a group of 111 destroyers built by the United States Navy in 1917-1919. Along with the 6 preceding Caldwell class and 155 subsequent Clemson-class destroyers, they formed the "flush-deck" or "four-stack" class. Only a few were completed in time to serve in World...
, and 14 Clemson class
Clemson class destroyer
The Clemson class was a series of 156 destroyers which served with the United States Navy from after World War I through World War II.The Clemson-class ships were commissioned by the United States Navy from 1919 to 1922, built by Newport News Shipbuilding & Dry Dock Company, New York Shipbuilding...
"flush-deck" destroyers built during and after World War I
World War I
World War I , which was predominantly called the World War or the Great War from its occurrence until 1939, and the First World War or World War I thereafter, was a major war centred in Europe that began on 28 July 1914 and lasted until 11 November 1918...
. Some of these had been previously converted to aircraft tenders or other uses.
In the conversion, the two forward boilers (out of four) were removed with their smokestacks (reducing speed to 25 knots). Accommodation for 200 troops was installed in the former engine spaces. The original armament of four 4" guns, one 3" AA gun
3"/23 caliber gun
The 3"/23 caliber gun was the standard anti-aircraft gun for United States destroyers through World War I and the 1920s...
, and twelve torpedo tubes was replaced with three modern 3" AA guns, one 40mm AA gun
Bofors 40 mm gun
The Bofors 40 mm gun is an anti-aircraft autocannon designed by the Swedish defence firm of Bofors Defence...
, and five 20mm AA guns
Oerlikon 20 mm cannon
The Oerlikon 20 mm cannon is a series of autocannons, based on an original design by Reinhold Becker of Germany, very early in World War I, and widely produced by Oerlikon Contraves and others...
. Two depth charge
Depth charge
A depth charge is an anti-submarine warfare weapon intended to destroy or cripple a target submarine by the shock of exploding near it. Most use explosives and a fuze set to go off at a preselected depth in the ocean. Depth charges can be dropped by either surface ships, patrol aircraft, or from...
racks and six anti-submarine mortars
Hedgehog (weapon)
The Hedgehog was an anti-submarine weapon developed by the Royal Navy during World War II, that was deployed on convoy escort warships such as destroyers to supplement the depth charge. The weapon worked by firing a number of small spigot mortar bombs from spiked fittings...
were carried. In place of the torpedo mounts, four davit mounted LCPL
LCPL
The Landing Craft Personnel was a landing craft used extensively in the Second World War. Its primary purpose was to ferry troops from transport ships to attack enemy-held shores. The craft derived from a prototype designed by the Eureka Tug-Boat Company of New Orleans, Louisiana, USA...
s (landing craft
Landing craft
Landing craft are boats and seagoing vessels used to convey a landing force from the sea to the shore during an amphibious assault. Most renowned are those used to storm the beaches of Normandy, the Mediterranean, and many Pacific islands during WWII...
) were shipped.
Buckley class conversions
The second group of APDs were converted from 45 Buckley classBuckley class destroyer escort
The Buckley class destroyer escorts were 102 destroyer escorts launched in the United States in 1943 - 1944. They served in World War II as convoy escorts and anti-submarine warfare ships. The lead ship was USS Buckley which was launched on 9 January 1943. The ships had General Electric steam...
destroyer escort
Destroyer escort
A destroyer escort is the classification for a smaller, lightly armed warship designed to be used to escort convoys of merchant marine ships, primarily of the United States Merchant Marine in World War II. It is employed primarily for anti-submarine warfare, but also provides some protection...
s (DE)s built in 1943-1945. These converted vessels were known as the Charles Lawrence class.
In the conversion, the superstructure was expanded to provide accommodation for 162 troops. The original gun armament of three 3" AA guns and and six 20mm AA guns
Oerlikon 20 mm cannon
The Oerlikon 20 mm cannon is a series of autocannons, based on an original design by Reinhold Becker of Germany, very early in World War I, and widely produced by Oerlikon Contraves and others...
was replaced with one 5" DP gun and six 40mm AA guns
Bofors 40 mm gun
The Bofors 40 mm gun is an anti-aircraft autocannon designed by the Swedish defence firm of Bofors Defence...
. The Charles Lawrence class retained the original three torpedo tubes, and carried two depth charge racks and eight ASW mortars.
Rudderow class conversions
The third group of APDs were converted from 51 Rudderow classRudderow class destroyer escort
The Rudderow class destroyer escorts were destroyer escorts launched in the United States in 1943 to 1945. Of this class, 22 were completed as destroyer escorts, and 50 were completed as Crosley-class high speed transport and were re-classified as High speed transport APDs. One ship was converted...
destroyer escort
Destroyer escort
A destroyer escort is the classification for a smaller, lightly armed warship designed to be used to escort convoys of merchant marine ships, primarily of the United States Merchant Marine in World War II. It is employed primarily for anti-submarine warfare, but also provides some protection...
s (DE)s built in 1943-1945. All but one of these was converted while under construction. These converted vessels were known as the Crosley class.
This conversion was the same as the Buckley class, except that the original armament had two 5" DP guns instead of three 3" guns; the after 5" gun was removed.
World War II service
As newer and more modern destroyers began joining the fleet some of the old ships were assigned to other duties such as tending seaplanes, laying or sweeping mines, or for a newer innovation in modern warfare, carrying fully equipped troops for assault landings as fast transports.The exigencies of the Guadalcanal Campaign
Guadalcanal campaign
The Guadalcanal Campaign, also known as the Battle of Guadalcanal and codenamed Operation Watchtower by Allied forces, was a military campaign fought between August 7, 1942 and February 9, 1943 on and around the island of Guadalcanal in the Pacific theatre of World War II...
, where neither side enjoyed the overwhelming local naval and air supremacy which insured victory in every other amphibious operation
Amphibious warfare
Amphibious warfare is the use of naval firepower, logistics and strategy to project military power ashore. In previous eras it stood as the primary method of delivering troops to non-contiguous enemy-held terrain...
of the war, necessitated an increase in the number of high-speed transports, hybrid warships which combined the functions of transports and destroyers. The concept of the high-speed transport embodied sufficient armament for the ship to defend herself against smaller warships and to support the troops she carried with sufficient speed to enable her to outrun more heavily armed ships.
Anti-submarine warfare
Anti-submarine warfare is a branch of naval warfare that uses surface warships, aircraft, or other submarines to find, track and deter, damage or destroy enemy submarines....
patrols and survey duties, operated with Underwater Demolition Team
Underwater Demolition Team
The Underwater Demolition Teams were an elite special-purpose force established by the United States Navy during World War II. They also served during the Korean War and the Vietnam War...
s and commando
Commando
In English, the term commando means a specific kind of individual soldier or military unit. In contemporary usage, commando usually means elite light infantry and/or special operations forces units, specializing in amphibious landings, parachuting, rappelling and similar techniques, to conduct and...
units, performed messenger and transport duties, conveyed passengers and mail to and from forward units, and were involved in mine sweeping operations. They were attacked by submarines, surface ships and aircraft (including kamikaze
Kamikaze
The were suicide attacks by military aviators from the Empire of Japan against Allied naval vessels in the closing stages of the Pacific campaign of World War II, designed to destroy as many warships as possible....
s), and many were damaged or sunk.
After World War II
Nine "flush deck" APDs were lost during the war. The remaining 23 were scrapped in 1945-1946.Some of the Charles Lawrence class and Crosley class APDs saw service in the Korean War
Korean War
The Korean War was a conventional war between South Korea, supported by the United Nations, and North Korea, supported by the People's Republic of China , with military material aid from the Soviet Union...
and Vietnam War
Vietnam War
The Vietnam War was a Cold War-era military conflict that occurred in Vietnam, Laos, and Cambodia from 1 November 1955 to the fall of Saigon on 30 April 1975. This war followed the First Indochina War and was fought between North Vietnam, supported by its communist allies, and the government of...
.
One Charles Lawrence class APD was lost during World War II. 14 were transferred to foreign navies in the 1960s. One was sold for commercial use as a floating power station. 26 were scrapped. On 1 January 1969, the remaining three were reclassified as "Fast Amphibious Transports" (LPR).
No Crosley class APD was lost during World War II. 18 were transferred to foreign navies. One was lost in a collision in 1966. Eight were sold as floating power stations. 18 were scrapped. In 1969, the remaining eight were reclassified as "Fast Amphibious Transports" (LPR).
See also
- List of United States Navy high-speed transports - St. Nazaire RaidSt. Nazaire RaidThe St Nazaire Raid or Operation Chariot was a successful British amphibious attack on the heavily defended Normandie dry dock at St Nazaire in German-occupied France during the Second World War. The operation was undertaken by the Royal Navy and British Commandos under the auspices of Combined...