A further development was the Landing Ship, Tank designation, built to support amphibious operations by carrying significant quantities of vehicles, cargo, and landing troops directly onto an unimproved shore. 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 tanks and other vehicles in amphibious assaults upon the continent of Europe. The first purpose-built LST design was . To carry 13 Churchill infantry tanks, 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.