T2 Tanker Pages

T2 Tanker Pages

A Brief History of the T2 Tanker

As a lifelong student of maritime and naval history, I became interested in some ships of our merchant fleet. My father was a Merchant Seaman, sailing as an engineer in several vessels before, during, and after World War II. (Check out his page here.) Included in the list of ships he sailed in were seven T2 tankers. After a small amount of research, I found that there are no T2 tankers preserved as museum ships as there are Liberty ships and Victory ships.

Following World War II, there wasn’t much need for the Liberty and Victory hulls, as there were already bigger and better cargo ships plying the trade more efficiently. But on the other hand, we had developed a profound thirst for petroleum products. Automobiles were being produced for the public again. Air travel had become a standard. All this required gasoline, diesel, and lubricating oils. We had to have a way of getting it here, and to the rest of the world. To meet that end, the Maritime Commission, after much lobbying by the petroleum and shipping industries, allowed the sale of the T2 tankers it had built for the war.

The General T2 Type Tanker

The T2 tanker design was first adapted from S.S. Mobilfuel and S.S. Mobilube, built for the Socony-Vacuum Company (later to become Mobile Oil). They were 501 feet six inches long overall, with a beam of 68 feet. They were rated at 9,900 tons gross, and a deadweight tonnage of 15,850 tons. They displaced about 21,100 tons. Six of these ships were built by Bethlehem-Sparrows Point Shipyard in Maryland.

The T2-A type tanker was another variety of the T2 design. These 5 ships were built by Sun Shipbuilding and Drydock Co., Chester, PA for the Keystone Tankship Corporation and its affiliates in 1940. The Navy took them over before construction was complete in 1942 to use as Navy oilers. They were 526 feet long, 68 feet abeam, rated at 10,600 tons gross and a deadweight tonnage of 16,300. They displaced about 22,445 tons. Propulsion was provided by geared steam turbines driving a single propeller at 12,000 shaft horsepower, giving a maximum rated speed of 16 and a half knots.

The T2-SE-A1 Type

The most common variety of the T2 style tanker was the United States Maritime Commission type T2-SE-A1, a commercial design already being built by Sun Shipbuilding Company for Standard Oil Company of New Jersey. There were 481 of these built between 1942 and 1945. Propulsion was provided by a turbo-electric drive. This consisted of a steam turbine generator connected to a propulsion motor to turn the propeller, thus obviating the need for a large main reduction gear, which would have taken quite a lot of time and machinery to produce, machinery that was already busy making these gear sets for naval vessels. These ships were built by Alabama Drydock & Shipbuilding Company of Mobile, Alabama, the Kaiser Company’s Swan Island Yard at Portland, Oregon, the Marinship Corporation at Sausalito, California and the Sun Shipbuilding & Drydock Company of Chester, Pennsylvania in extremely short production times. The average production time from laying of the keel to completion for sea trials was about 70 days, including 55 in the building ways and another 15 in the fitting out dock. The record was held by Marinship Corporation, completing S.S. Huntington Hills in just 33 days; 28 days on the way and 5 days of fitting out!

These ships were 523 feet 6 inches long, 68 feet abeam and carried a gross rated tonnage of 10,448. Deadweight tonnage was 16,613 and they displaced about 21,880 tons. The turbo-electric propulsion system delivered 6,000 shaft horsepower, with a maximum power of 7,240 horsepower giving a top rated speed of about 15 knots with a cruising range of about 12,600 miles. (The A2 and A3 versions of the T2 had 10,000 SHP propulsion machinery, developing a top speed of 16 knots.) The propulsion machinery was produced by the General Electric Company, Lynn MA; the Elliott Company, Jeanette, PA; and the Westinghouse Electric and Manufacturing Company of Pittsburgh, PA.

The T2-SE-A1 tankers were not the first to have turbo-electric propulsion, nor was it a novel innovation. During World War I there were several commercial ships and some naval vessels propelled by turbo-electric plants. In 1938, some tankers built for the Atlantic Refining Company of Philadelphia, PA by Sun Shipbuilding Company were given turbo-electric plants. S.S. J. W. Van Dyke and S.S. Robert H. Colley had General Electric equipment giving them 6,040 SHP and a top speed of about 13.5 knots. Atlantic Refining had five more of this type of ship built.

The T2-SE-A1 had 9 sets of tanks. Tanks 2 through 9 had a main center tank carrying 391,500 gallons, and two side tanks (one port, one starboard) carrying about 165,000 gallons each. Tank number one consisted of only two side by side tanks, divided by a common bulkhead, as this tank set was only 13 feet 6 inches long. Tank sets 2 through 9 were 36 feet 6 inches long. Total cargo was about 5,930,000 gallons, about 141,200 barrels. There was also a small dry cargo space of about 15,200 cubic feet located forward of Tank Number 1 above the deep tank for a very small amount of dry cargo. There were two pumprooms, one forward and one aft. The main pumproom was aft, and contained six pumps. There were three large capacity pumps of 2,000 gallons per minute which were driven by electric motors located in an adjacent machinery space. There were also two 400 GPM pumps and one 700 GPM pump. In the forward pumproom was one 700 GPM pump and and 300 GPM pump which were reciprocating pumps used for fuel transfer and stripping.

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