.30-calibre (7.62 mm) and .50-calibre (12.7 mm), range depending on the operating country. Conversions and modifications Several special purpose versions were created for use during the Normandy landings. The British created the Landing Craft Tank (Rocket) (LCT(R)) modified to fire salvoes of three-inch RP-3 rockets, while the Landing Craft Guns (Large) (LCG(L)) was armed with two QF 4.7 inch guns, eight Oerlikon 20 mm AA guns and two 2-pounder pom-poms. These ships did not beach; their mission was close-in gunfire support. The Landing Craft Tank (Armoured) (LCT(A)) was designed for use by the first wave and was equipped with additional armour protection for the crew stations and on the bows, while a heavy wooden ramp allowed the two forward tanks to fire forward. These were all U.S-built LCT Mk.5s, which had been provided under Lend-Lease to the British for Mediterranean operations, then "reverse lend-leased" back to the U.S. for the invasion. The Landing Craft Tank (self-propelled) (LCT(SP)) carried self-propelled guns for fire support; in U.S. vessels these were 155 mm, while the British used M7 105 mm self-propelled guns and called them "Landing Craft Tank (High Explosive)" (LCT(HE)). A related variant was the British Landing Craft Tank (Concrete Buster) (LCT(CB)), which carried three British Sherman Firefly tanks fitted with the 17-pounder high velocity gun, specifically deployed to attack fortifications. Other variants included the Landing Craft Tank (Hospital) (LCT(H)) for casualty evacuation, and one LCT served as a floating bakery at Normandy. Some LCTs with specialised weaponry were used as floating anti-aircraft batteries. These were often manned by mixed army and navy crews. Others were modified after the war for uses such as dredging. Post-war Unlike most wartime landing craft, the LCT remained in active duty with the U.S. Navy after the war, and many LCTs were also loaned or given to the post-war navies of Allied countries. In early 1949, their designation was changed to landing ship utility (LSU), and changed again in late 1949 to landing craft utility (LCU). New landing craft (the LCU 1488-, 1610-, 1627- and 1646-classes) were also built to a modified Mark 5 design. Some were later reclassified during the Vietnam War as harbour utility craft (YFUs) as they no longer served in an amphibious assault role, but were used in harbor support roles such as transporting goods from supply ships; however, the YFU-71-class were 11 "Skilak" lighters purchased as 'commercial off-the-shelf', and so were