US World War II Amphibious Tactics

A ""typical"" Attack Force delivering an infantry or Marine division was built around the Landing Force, with a transport group of two or three transport divisions, each with three or four attack transports, an attack cargo ship, an LSD, and possibly a troop transport in lieu of the fourth attack transport. The Tractor Group might include eight to ten LSTs carrying amtracs. The Control Group would consist of a few submarine chasers and small control boats to coordinate and guide the assault waves; and destroyer-transports (APDs) carrying UDTs were usually assigned to the Control Group. A half-dozen or so destroyers comprised the Transport Screen. The Fire Support Group might consist of two or four old 14in-gun battleships, two or three heavy and light cruisers, eight to ten more destroyers, and one or two LCI divisions, each with six rocket-firing LCI gunboats. Fire Support Groups were usually subdivided into mixed ""units"" of several types of ships assigned specific target areas. The Carrier Support Group had three escort carriers, each with nearly 30 fighters and torpedo-bombers to provide close air support, and escorted by three or four destroyers. A Mine Sweeping & Hydrographic Group of varied size was necessary to sweep the approaches and entry channels. There would also be a mixed bag of defense and garrison groups transporting follow-on forces to hold and develop bases on the islands; these would be transported aboard LSTs, troop transports, and cargo ships. A Floating Reserve would be carried in similar ships or in attack transports. Service, salvage, and fueling groups might also be involved.