Landing Ship, Infantry
(LSI) was a British term for a type of ship used to transport infantry
in amphibious warfare
during the Second World War
The LSI would take its cargo of infantry close to the target area. They would then transfer to landing craft, such as the Landing Craft, Assault for the journey to the beach. A small LSI would be around 3,000 gross registered tons and could carry up to 800 troops. The largest LSI(L) could carry 1,800 and would need 20 or so landing craft for that number.
LSI were generally converted cross-channel ferries and other similar ships of that size or converted passenger ships
Conversion was accomplished by adding davits for the landing craft plus some defensive armament such as 12-pounder guns and anti-aircraft guns such as the 20mm Oerlikon.
Post-war the US renamed their Landing Craft, Infantry as "Landing Ship Infantry" - these were vessels that could beach and carried around 200 troops.
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