Landing Ship , Tank Landing Ship , Tank ( LST ) is the military designation for naval vessels created during World War II to support amphibious operation s by carrying significant quantities of vehicles , cargo , and landing troops directly onto an unimproved shore . The first tank landing ships were built to British requirements by converting existing ships . This was followed by the development of a purpose built ship . Thereafter , the British and US collaborated upon a joint design with the majority of the construction carried out by the US and supplied under lend - lease . The majority , a thousand , were laid down in the United States during World War II for use by the Allies . Eighty more were built in the United Kingdom and Canada . LST Mk . 1 . The British evacuation from Dunkirk in 1940 demonstrated to the Admiralty that the Allies needed relatively large , ocean - going ships capable of shore - to - shore delivery of tank s and other vehicles in amphibious assault s upon the continent of Europe . As an interim measure , three 4000 to 4800 GRT tankers , built to pass over the restrictive bars of Lake Maracaibo , Venezuela , were selected for conversion because of their shallow draft . Bow doors and ramps were added to these ships , which became the first tank landing ships , " LST ( 1 ) " : , and . They later proved their worth during the invasion of Algeria in 1942 , but their bluff bows made for inadequate speed and pointed up the need for an all - new design incorporating a sleeker hull . The first purpose - built LST design was . It was a scaled down design from ideas penned by Churchill . To carry 13 Churchill infantry tank s , 27 vehicles and nearly 200 men ( in addition to the crew ) at a speed of 18 knots , it could not have the shallow draught that would have made for easy unloading . As a result , each of the three ( " Boxer " , " Bruiser " , and " Thruster " ) ordered in March 1941 had a very long ramp stowed behind the bow doors . The three ships were converted to " Fighter Direction Ships " for the invasion of Normandy . The U . S . were to build seven LST ( 1 ) but in light of the problems with the design and progress with the LCT Mark II the plans were cancelled . Construction of the LCT ( 1 ) s took until 1943 and the first US LCT ( 2 ) was launched before them . LST Mk . 2 . Development . At their first meeting at the Atlantic conference in Argentia , Newfoundland in August 1941 , President Franklin D . Roosevelt and Prime Minister Winston Churchill confirmed the Admiralty ' s views . In November 1941 , a small delegation from the Admiralty arrived in the United States to pool ideas with the United States Navy ' s Bureau of Ships with regard to development of ships and also including the possibility of building further " Boxer " s in the US . During this meeting , it was decided that the Bureau of Ships would design these vessels . As with the standing agreement these would be built by the US so British shipyards could concentrate on building vessels for the Royal Navy . The specification called for vessels capable of crossing the Atlantic and the original title given to them was " Atlantic Tank Landing Craft " ( Atlantic ( T . L . C . ) ) . Calling a vessel long a " craft " was considered a misnomer and the type was re - christened " Landing Ship , Tank ( 2 ) " , or " LST ( 2 ) " . The LST ( 2 ) design incorporated elements of the first British LCTs from their designer , Sir Rowland Baker , who was part of the British delegation . This included sufficient buoyancy in the ships ' sidewalls that they would float even with the tank deck flooded . The LST ( 2 ) gave up the speed of HMS " Boxer " at only 10 knots but had a similar load while drawing only 3 feet forward when beaching . Design . Within a few days , John C . Niedermair of the Bureau of Ships sketched out an awkward looking ship that proved to be the basic design for the more than 1 , 000 " LST ( 2 ) " that were built during World War II . To meet the conflicting requirements of deep draft for ocean travel and shallow draft for beaching , the ship was designed with a large ballast system that could be filled for ocean passage and pumped out for beaching operations . An anchor and mechanical winch system also aided in the ship ' s ability to pull itself off the beach . The rough sketch was sent to Britain on 5 November 1941 and accepted immediately . The Admiralty then requested the United States to build 200 " LST ( 2 ) " for the Royal Navy under the terms of lend - lease . The preliminary plans initially called for an LST 280 feet ( 85 m ) in length ; but , in January 1942 , the Bureau of Ships discarded these drawings in favor of specifications for a ship long . Within a month , final working plans were developed that further stretched the overall length to 328 feet ( 100 m ) and called for a 50 - foot ( 15 m ) beam and minimum draft of 3 . 8 feet ( 1 . 2 m ) . This scheme distributed the ship ' s weight over a greater area , enabling her to ride higher in the water when in landing trim . The LST could carry a 2 , 100 - ton ( 1 , 900 t ) load of tanks and vehicles . The larger dimensions also permitted the designers to increase the width of the bow door opening and ramp from 12 to 14 feet ( 3 . 7 to 4 . 3 m ) and thus accommodate most Allied vehicles . As the dimensions and weight of the LST increased , steel plating thickness increased from to on the deck and sides with 1 - inch - thick plating under the bow . By January 1942 , the first scale model of the LST had been built and was undergoing tests at the David Taylor Model Basin in Washington , D . C . Provisions were made for the satisfactory ventilation of the tank space while the tank motors were running , and an elevator was provided to lower vehicles from the main deck to the tank deck for disembarking . In April 1942 a mock - up of the well - deck of an LST was constructed at Fort Knox , Kentucky to resolve the problem of ventilation within the LST well - deck . The interior of the building was constructed to duplicate all the features found within an actual LST . Being the home to the Armored Force Board , Fort Knox supplied tanks to run on the inside while Naval architects developed a ventilation system capable of evacuating the well - deck of harmful gases . Testing was completed in three months . This historic building remains at Fort Knox today . Early LST operations required overcoming the 18th century language of the Articles for the Government of the United States Navy : " He who doth suffer his ships to founder on rocks and shoals shall be punished . . . " There were some tense moments of concept testing at Quonset , Rhode Island in early 1943 when designer Niedermair encouraged the commanding officer of the first U . S . LST to drive his ship onto the beach at full speed of . Production . In three separate acts dated 6 February 1942 , 26 May 1943 , and 17 December 1943 , Congress provided the authority for the construction of LSTs along with a host of other auxiliaries , destroyer escort s , and assorted landing craft . The enormous building program quickly gathered momentum . Such a high priority was assigned to the construction of LSTs that the previously laid keel of an aircraft carrier was hastily removed to make room for several LSTs to be built in her place . The keel of the first LST was laid down on 10 June 1942 at Newport News , Va . , and the first standardized LSTs were floated out of their building dock in October . Twenty - three were in commission by the end of 1942 . The LST building program was unique in several respects . As soon as the basic design had been developed , contracts were let and construction was commenced in quantity before the completion of a test vessel . Preliminary orders were rushed out verbally or by telegrams , telephone , and air mail letters . The ordering of certain materials actually preceded the completion of design work . While many heavy equipment items such as main propulsion machinery were furnished directly by the Navy , the balance of the procurement was handled centrally by the Material Coordinating Agency — an adjunct of the Bureau of Ships — so that the numerous builders in the program would not have to bid against one another . Through vigorous follow - up action on materials ordered , the agency made possible the completion of construction schedules in record time . The need for LSTs was urgent , and the program enjoyed a high priority throughout the war . Since most shipbuilding activities were located in coastal yards and were largely used for construction of large , deep - draft ships , new construction facilities were established along inland waterways . In some instances , heavy - industry plants such as steel fabrication yards were converted for LST construction . This posed the problem of getting the completed ships from the inland building yards to deep water . The chief obstacles were bridges . The Navy successfully undertook the modification of bridges and , through a " Ferry Command " of Navy crews , transported the newly constructed ships to coastal ports for fitting out . The success of these " cornfield " shipyards of the Middle West was a revelation to the long - established shipbuilders on the coasts . Their contribution to the LST building program was enormous . Of the 1 , 051 LSTs built during World War II , 670 were constructed by five major inland builders . Chicago Bridge and Iron shipyard in Seneca , Illinois launched 156 ships and was specifically chosen because of their reputation and skills , particularly in welding . The most LSTs constructed during World War II were built in Evansville , Indiana , by Missouri Valley Bridge and Iron , & International Steel Co . Modifications . By 1943 , the construction time for an LST had been reduced to four months . By the end of the war , this had been cut to two months . Considerable effort was expended to hold the ship ' s design constant , but , by mid - 1943 , operating experience led to the incorporation of certain changes in the new ships . The LST - 491 " class replaced the elevator installed in the original LST - 1 " class , to transfer equipment between the tank deck and the main deck , with a ramp that was hinged at the main deck . This allowed vehicles to be driven directly from the main deck into the tank deck , and then across the bow ramp to the beach or causeway , speeding the process of disembarkation . Changes in the later " LST - 542 " class included the addition of a navigation bridge , the installation of a water distillation plant with a capacity of 4 , 000 gallons per day , the removal of the tank deck ventilator tubes from the center section of the main deck , the strengthening of the main deck to carry a smaller Landing Craft Tank ( LCT ) , and an upgrade in armor and armament , with the addition of a 3 " / 50 caliber gun .