T2 tanker
Encyclopedia
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
. The largest "navy oilers" after the T3s at the time, nearly 500 of them were built between 1940 and the end of 1945.
Many of them remained in service for decades after the war and like other World War II ships pressed into peace time service were the subject of safety concerns. A U.S. Coast Guard Marine Board of Investigation in 1952 stated they were prone to splitting in two in cold weather and the ships were then "belted" with steel straps. This occurred after two T-2s, the SS Pendleton and the SS Fort Mercer split in two off Cape Cod within hours of each other. Scientific inquiries into the problems suggested at first the tendency of the tankers to split in two was due to poor welding techniques. Later, it was concluded that the steel used in the war time construction had too high a sulfur content that turned the steel brittle at lower temperatures.
T2 design
The T2 design was formalized by the United States Maritime CommissionUnited States Maritime Commission
The United States Maritime Commission was an independent executive agency of the U.S. federal government that was created by the Merchant Marine Act of 1936, passed by Congress on June 29, 1936, and replaced the U.S. Shipping Board which had existed since World War I...
as its medium-sized "National Defense tanker," a ship built for merchant service which could be militarized as a fleet auxiliary in time of war. MarCom subsidized the excess cost of naval features beyond normal commercial standards. The T2 was based on two ships built in 1938-39 by Bethlehem Steel
Bethlehem Steel
The Bethlehem Steel Corporation , based in Bethlehem, Pennsylvania, was once the second-largest steel producer in the United States, after Pittsburgh, Pennsylvania-based U.S. Steel. After a decline in the U.S...
for Socony-Vacuum Oil Company
Mobil
Mobil, previously known as the Socony-Vacuum Oil Company, was a major American oil company which merged with Exxon in 1999 to form ExxonMobil. Today Mobil continues as a major brand name within the combined company, as well as still being a gas station sometimes paired with their own store or On...
, Mobilfuel and Mobilube, differing from the Mobil ships principally in the installation of more powerful engines for higher speed. Standard T2s were 501 in 6 in (152.86 m) in total length, with a beam of 68 feet (20.7 m). Rated at 9,900 tons gross (GRT
Tonnage
Tonnage is a measure of the size or cargo carrying capacity of a ship. The term derives from the taxation paid on tuns or casks of wine, and was later used in reference to the weight of a ship's cargo; however, in modern maritime usage, "tonnage" specifically refers to a calculation of the volume...
), with , standard T2s displaced about 21,100 tons. Steam turbines driving a single propeller
Propeller
A propeller is a type of fan that transmits power by converting rotational motion into thrust. A pressure difference is produced between the forward and rear surfaces of the airfoil-shaped blade, and a fluid is accelerated behind the blade. Propeller dynamics can be modeled by both Bernoulli's...
at 12000 hp delivered a top speed of 16 knots (31.4 km/h). Six were built for commerce
Commerce
While business refers to the value-creating activities of an organization for profit, commerce means the whole system of an economy that constitutes an environment for business. The system includes legal, economic, political, social, cultural, and technological systems that are in operation in any...
by Bethlehem-Sparrows Point Shipyard in Maryland
Maryland
Maryland is a U.S. state located in the Mid Atlantic region of the United States, bordering Virginia, West Virginia, and the District of Columbia to its south and west; Pennsylvania to its north; and Delaware to its east...
, only to be taken over by the United States Navy
United States Navy
The United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined. The U.S...
following the attack on Pearl Harbor
Attack on Pearl Harbor
The attack on Pearl Harbor was a surprise military strike conducted by the Imperial Japanese Navy against the United States naval base at Pearl Harbor, Hawaii, on the morning of December 7, 1941...
as the Kennebec class
Kennebec class oiler
The Kennebec-class oilers were sixteen United States Navy medium oilers built during World War II to three related designs at Bethlehem Sparrows Point Shipyard of Sparrows Point, Maryland and Sun Shipbuilding & Drydock Co. of Chester, Pennsylvania, all of which survived the war...
.
T2-A design
Keystone Tankships company ordered five tankers in 1940 from Sun Shipbuilding & Drydock of Chester, PA, based on the T2 but longer and with increased capacity; Marcom would designate this design T2-A. Bigger but faster, they were 526 feet (160.3 m) in total length, displaced about 22,445 tons, and were rated at 10,600 tons gross with -- yet they attained a top speed approaching 16.5 knots (32.3 km/h). All five were requisitioned by the Navy during the war and converted to fleet oilers as the Mattaponi class.T2-SE-A1
By far the most common variety of the T2-type tanker was the T2-SE-A1, another commercial design already being built in 1940 by the Sun Shipbuilding Company for Standard Oil Company of New Jersey. They were 523 feet (159.4 m) long, 68 feet (20.7 m) abeam, with and . Their turbo-electricTurbo-electric
A turbo-electric transmission uses electric generators to convert the mechanical energy of a turbine into electric energy and electric motors to convert it back into mechanical energy to power the driveshafts....
propulsion
Marine propulsion
Marine propulsion is the mechanism or system used to generate thrust to move a ship or boat across water. While paddles and sails are still used on some smaller boats, most modern ships are propelled by mechanical systems consisting a motor or engine turning a propeller, or less frequently, in jet...
system delivered 6,000 shaft horsepower, with maximum thrust
Thrust
Thrust is a reaction force described quantitatively by Newton's second and third laws. When a system expels or accelerates mass in one direction the accelerated mass will cause a force of equal magnitude but opposite direction on that system....
of 7240 hp, which produced a top-rated speed of about 15 knots (29.4 km/h) with a cruising range of up to 12600 miles (20,277.7 km). After Pearl Harbor, the United States Maritime Commission
United States Maritime Commission
The United States Maritime Commission was an independent executive agency of the U.S. federal government that was created by the Merchant Marine Act of 1936, passed by Congress on June 29, 1936, and replaced the U.S. Shipping Board which had existed since World War I...
ordered this model built en masse to supply U.S. warships already in accelerated production. 481 were built in extremely short production times by the Alabama Drydock and Shipbuilding Company
Alabama Drydock and Shipbuilding Company
The Alabama Drydock and Shipbuilding Company located in Mobile, Alabama, was one of the largest marine production facilities in the United States of America during the 20th century. Beginning operation in 1917, the shipyard is presently owned by The Lehman Group The Alabama Drydock and...
of Mobile, Alabama
Mobile, Alabama
Mobile is the third most populous city in the Southern US state of Alabama and is the county seat of Mobile County. It is located on the Mobile River and the central Gulf Coast of the United States. The population within the city limits was 195,111 during the 2010 census. It is the largest...
, the Kaiser Company
Kaiser Shipyards
The Kaiser Shipyards were seven major shipbuilding yards located mostly on the U.S. west coast during World War II. They were owned by the Kaiser Shipbuilding Company, a creation of American industrialist Henry J...
at their Swan Island Yard at Portland, Oregon
Portland, Oregon
Portland is a city located in the Pacific Northwest, near the confluence of the Willamette and Columbia rivers in the U.S. state of Oregon. As of the 2010 Census, it had a population of 583,776, making it the 29th most populous city in the United States...
, the Marinship Corp.
Marinship
Marinship Corporation was a shipbuilding company of the United States during World War II, created to build the shipping required for the war effort...
of Sausalito, California
Sausalito, California
Sausalito is a San Francisco Bay Area city, in Marin County, California, United States. Sausalito is south-southeast of San Rafael, at an elevation of 13 feet . The population was 7,061 as of the 2010 census. The community is situated near the northern end of the Golden Gate Bridge, and prior to...
and the Sun Shipbuilding and Drydock Company of Chester, Pennsylvania
Chester, Pennsylvania
Chester is a city in Delaware County, Pennsylvania, United States, with a population of 33,972 at the 2010 census. Chester is situated on the Delaware River, between the cities of Philadelphia and Wilmington, Delaware.- History :...
. During that period, average production time from laying of the keel
Keel
In boats and ships, keel can refer to either of two parts: a structural element, or a hydrodynamic element. These parts overlap. As the laying down of the keel is the initial step in construction of a ship, in British and American shipbuilding traditions the construction is dated from this event...
to "fitting out" was 70 days. The record, however, was held by Marinship, which had the SS Huntington Hills ready for sea trial
Sea trial
A sea trial is the testing phase of a watercraft . It is also referred to as a "shakedown cruise" by many naval personnel. It is usually the last phase of construction and takes place on open water, and can last from a few hours to many days.Sea trials are conducted to measure a vessel’s...
s in just 33 days.
T2-SE-A2 and -A3
The T2-SE-A2 variation, built only by Marinship of Sausalito, was nearly identical to the T2-SE-A1 version, only with maximum thrust of 10000 hp rather than the former’s 7,240. The A3 variation was essentially an A2 built as a Navy oiler from the start, rather than converted later as many A2s were.
T3-S-A1
Despite the confusing T3 designation, the T3-S-A1s bult by Bethlehem Sparrows Point for Standard Oil of New Jersey were identical to the original T2s except for having less powerful engines of 7700 hp. 25 of this design were ordered by the Maritime Commission, of which five became Navy oilers as the Chiwawa classChiwawa class oiler
The Chiwawa-class oilers were United States Navy oilers of the T3-S-A1 design built during World War II at Bethlehem Sparrows Point Shipyard of Sparrows Point, Maryland...
.
See also
- List of Type T2 Tanker names
- Liberty shipLiberty shipLiberty ships were cargo ships built in the United States during World War II. Though British in conception, they were adapted by the U.S. as they were cheap and quick to build, and came to symbolize U.S. wartime industrial output. Based on vessels ordered by Britain to replace ships torpedoed by...
- Type C1 shipType C1 shipType C1 was a designation for small cargo ships built for the U.S. Maritime Commission before and during World War II. The first C1 types were the smallest of the three original Maritime Commission designs, meant for shorter routes where high speed and capacity were less important. Only a handful...
- Type C2 shipType C2 shipType C2 ships were designed by the United States Maritime Commission in 1937-38. They were all-purpose cargo ships with five holds, and U.S. shipyards built 173 of them from 1939-1945. Compared to ships built before 1939, the C2s were remarkable for their speed and fuel economy. Their design speed...
- Victory shipVictory shipThe Victory ship was a type of cargo ship produced in large numbers by North American shipyards during World War II to replace shipping losses caused by German submarines...
- Kennebec class oilerKennebec class oilerThe Kennebec-class oilers were sixteen United States Navy medium oilers built during World War II to three related designs at Bethlehem Sparrows Point Shipyard of Sparrows Point, Maryland and Sun Shipbuilding & Drydock Co. of Chester, Pennsylvania, all of which survived the war...
- Chiwawa class oilerChiwawa class oilerThe Chiwawa-class oilers were United States Navy oilers of the T3-S-A1 design built during World War II at Bethlehem Sparrows Point Shipyard of Sparrows Point, Maryland...
- Suamico class oilerSuamico class oilerThe Suamico class were a class of 25 oilers of the United States Navy during WWII. Built to the Maritime Commission T2-SE-A1 , -A2 and -A3 designs, they used turbo-electric propulsion, obviating the need for reduction gearing, a major issue in US mass-production shipbuilding.-The Suamicos:Just...
- Escambia class oiler, a T2 tanker, lost in the Bermuda TriangleBermuda TriangleThe Bermuda Triangle, also known as the Devil's Triangle, is a region in the western part of the North Atlantic Ocean where a number of aircraft and surface vessels allegedly disappeared under mysterious circumstances....
, a T2 tanker, mistakenly believed to have been lost in the Bermuda Triangle - SS Marine ElectricSS Marine ElectricSS Marine Electric, a 605-foot bulk carrier, sank on 12 February 1983, about 30 miles off the coast of Virginia, in 130 feet of water. Thirty-one of the 34 crewmembers were killed; the three survivors endured 90 minutes drifting in the frigid waters of the Atlantic. The wreck resulted in some of...
, a T2 tanker that sank in 1983 storm, the investigation of which lead to major reforms in ship inspections and safety standards.