Type C2 ship
Type C2 ships were designed by the United States Maritime Commission (MARCOM) in 1937–38. They were all-purpose cargo ships with five holds, and U.S. shipyards built 328 of them from 1939 to 1945. Compared to ships built before 1939, the C2s were remarkable for their speed and fuel economy. Their design speed was , but some could make on occasion. The first C2s were long, broad, and deep, with a draft. Later ships varied somewhat in size. Some, intended for specific trade routes, were built with significant modifications in length and capacity. In 1937, MARCOM distributed tentative  designs for criticism by shipbuilders, ship owners, and naval architects. The final designs incorporated many changes suggested by these constituencies. The ships were to be reasonably fast but economical cargo ships which, with some government subsidies to operators, could compete with vessels of other nations. Building costs were to be minimized by standardization of design and equipment, and the ships were to have sufficient speed and stability that they could be used as naval auxiliaries in time of national emergency. The basic specifications called for a five-hold steel cargo ship with raked stem and cruiser stern, complete shelter and  second decks, and a third deck in Nos. 1–4 holds. Dimensions of the hatches were , except for No. 2, which was , allowing such cargo as locomotives, naval guns, long bars, etc. Ventilation to the holds was provided by hollow kingposts, which also served as cargo masts. Cargo handling gear consisted of fourteen 5-ton cargo booms, plus two 30-ton booms at Nos. 3 and 4 hatches. Living accommodations were much improved over previous designs, with crew accommodations amidships, officers quarters on the boat deck, and the captain's quarters on the bridge deck, along with the wheelhouse, chartroom, gyro  and radio room. Hot and cold running water was provided throughout. Many of the ships such as SS "Donald McKay" were converted by the U.S. Navy for service during World War II. The commercial versions were operated by the government during the war. Beginning in late 1945, the commercial ships were sold to merchant shipping lines, with service until the early 1970s. Cost. According to the War Production Board, in 1943 the C-2 had a relative cost of $313 per deadweight ton (10,800 deadweight tonnage) for $3,380,400; which at $14 to $1 inflation of 1945 to  2020 amounts to $48,136,896