Amphibious cargo ships were U.S. Navy ships designed specifically to carry troops, heavy equipment and supplies in support of amphibious assaults, and to provide naval gunfire support during those assaults. A total of 108 of these ships were built between 1943 and 1945—which worked out to an average of one ship every eight days. Six additional AKAs, featuring new and improved designs, were built in later years.They were originally called Attack Cargo Ships and designated AKA. In 1969, they were renamed as Amphibious Cargo Ships and redesignated LKA.
Compared to other cargo ship types, these ships could carry landing craft, were faster, had more armament, and had larger hatches and booms. Their holds were optimized for combat loading, a method of cargo storage where the items first needed ashore were at the top of the hold, and those needed later were lower down. Because these ships went into forward combat areas, they had Combat Information Centers and significant amounts of equipment for radio communication, neither of which were present in other cargo ships.
A cargo ship or freighter is any sort of ship or vessel that carries cargo, goods, and materials from one port to another. Thousands of cargo carriers ply the world's seas and oceans each year, handling the bulk of international trade. Cargo ships are usually specially designed for the task, often being equipped with cranes and other mechanisms to load and unload, and come in all sizes. Today, they are almost always built by welded steel, and with some exceptions generally have a life expectancy of 25 to 30 years before being scrapped.
Cargo ships/freighters can be divided into five groups, according to the type of cargo they carry. These groups are:
General cargo vessels carry packaged items like chemicals, foods, furniture, machinery, motor- and military vehicles, footwear, garments, etc.
Tankers carry petroleum products or other liquid cargo.
Dry bulk carriers carry coal, grain, ore and other similar products in loose form.