Balao class submarine
The Balao class was a successful design of 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...

A submarine is a watercraft capable of independent operation below the surface of the water. It differs from a submersible, which has more limited underwater capability...

 used during World War II
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...

, and with 122 units built, the largest class of submarines in the United States Navy. An improvement on the earlier Gato
Gato class submarine
The United States Navy Gato class submarine formed the core of the submarine service that was largely responsible for the destruction of the Japanese merchant marine and a large portion of the Imperial Japanese Navy in World War II...

 class, the boats had slight internal differences. The most significant improvement was the use of thicker, higher yield strength
Yield (engineering)
The yield strength or yield point of a material is defined in engineering and materials science as the stress at which a material begins to deform plastically. Prior to the yield point the material will deform elastically and will return to its original shape when the applied stress is removed...

 steel in the pressure hull skins and frames, which increased their test depth to 400 feet (121.9 m). Tang actually achieved a depth of 612 ft (186.5 m) during a test dive,
and exceeded that test depth when taking on water in the forward torpedo room while evading a destroyer.


The propulsion of the Balao-class submarines was generally similar to that of the preceding Gato-class
Gato class submarine
The United States Navy Gato class submarine formed the core of the submarine service that was largely responsible for the destruction of the Japanese merchant marine and a large portion of the Imperial Japanese Navy in World War II...

. Like their predecessors, they were true diesel-electric
Diesel-electric transmission or diesel-electric powertrain is used by a number of vehicle and ship types for providing locomotion.A diesel-electric transmission system includes a diesel engine connected to an electrical generator, creating electricity that powers electric traction motors...

 submarines: their four diesel engine
Diesel engine
A diesel engine is an internal combustion engine that uses the heat of compression to initiate ignition to burn the fuel, which is injected into the combustion chamber...

s powered electrical generator
Electrical generator
In electricity generation, an electric generator is a device that converts mechanical energy to electrical energy. A generator forces electric charge to flow through an external electrical circuit. It is analogous to a water pump, which causes water to flow...

s, and electric motor
Electric motor
An electric motor converts electrical energy into mechanical energy.Most electric motors operate through the interaction of magnetic fields and current-carrying conductors to generate force...

s drove the shafts. There was no direct connection between the main engines and the shafts.

Balao-class submarines received main engines from one of two manufacturers. Fairbanks-Morse
Fairbanks Morse and Company was a manufacturing company in the late 19th and early 20th century. Originally a weighing scale manufacturer, it later diversified into pumps, engines, windmills, locomotives and industrial supplies until it was merged in 1958...

 supplied Model 38D8-⅛ opposed piston engines, and General Motors
General Motors
General Motors Company , commonly known as GM, formerly incorporated as General Motors Corporation, is an American multinational automotive corporation headquartered in Detroit, Michigan and the world's second-largest automaker in 2010...

' Electro-Motive Diesel division supplied Model 16 V16 engine
V16 engine
A V16 engine is a V engine with 16 cylinders. Engines of this number of cylinders are uncommon in automotive use.A V16 engine is perfectly balanced regardless of the V angle without requiring counter-rotating balancing shafts which are necessary to balance Straight-4 and odd number of cylinder...

s. Earlier Fairbanks-Morse boats received a 9-cylinder
Cylinder (engine)
A cylinder is the central working part of a reciprocating engine or pump, the space in which a piston travels. Multiple cylinders are commonly arranged side by side in a bank, or engine block, which is typically cast from aluminum or cast iron before receiving precision machine work...

 version of the Model 38D8-⅛, while boats from onward received 10-cylinder engines. Earlier GM boats received Model 16-248 engines, but beginning with Model 16-278A engines were used. In each case, the newer engines had greater displacement
Engine displacement
Engine displacement is the volume swept by all the pistons inside the cylinders of an internal combustion engine in a single movement from top dead centre to bottom dead centre . It is commonly specified in cubic centimeters , litres , or cubic inches...

 than the old, but were rated at the same power; they operated at lower mean effective pressure
Mean effective pressure
The mean effective pressure is a quantity related to the operation of an reciprocating engine and is a valuable measure of an engine's capacity to do work that is independent of engine displacement. When quoted as an indicated mean effective pressure or imep , it may be thought of as the average...

 for greater reliability.

Two submarines, and , were to receive Hooven-Owens-Rentschler
The firm of Hooven, Owens, Rentschler, and Company manufactured steam and diesel engines in Hamilton, Ohio. Because the firm was frequently known by its initials, H.O.R., the Hooven is sometimes incorrectly rendered as Hoover, and the Owens may be mistaken for Owen.The firm was the successor to the...

 (H.O.R.) diesels, but both boats were cancelled.

Two manufacturers supplied electric motors for the Balao-class. Elliott Company
Elliott Company
Elliott Company designs, manufactures, installs, and services turbo-machinery for prime movers and rotating machinery. Headquartered in Jeannette, Pennsylvania, Elliott Company is a wholly owned subsidiary of the Japan-based company, Ebara Corporation, and is a unit of Elliott Group, Ebara...

 motors were fitted primarily to boats with Fairbanks-Morse engines. General Electric
General Electric
General Electric Company , or GE, is an American multinational conglomerate corporation incorporated in Schenectady, New York and headquartered in Fairfield, Connecticut, United States...

 motors were fitted primarily to boats with General Motors engines, but some Fairbanks-Morse boats received GE motors. Allis-Chalmers
The Allis-Chalmers Manufacturing Co. of West Allis, Wisconsin, is an American company known for its past as a manufacturer with diverse interests, perhaps most famous for their bright Persian Orange farm tractors...

 motors were to be used in SS-530 through SS-536, but those seven boats were cancelled before even receiving names.

Earlier submarines carried four high-speed electric motors (two per shaft), which had to be fitted with reduction gears to slow their outputs down to an appropriate speed for the shafts. This reduction gearing was very noisy, and made the submarine easier to detect with hydrophone
A hydrophone is a microphone designed to be used underwater for recording or listening to underwater sound. Most hydrophones are based on a piezoelectric transducer that generates electricity when subjected to a pressure change...

s. A handful of late Balao-class submarines received low-speed double armature
Armature (electrical engineering)
In electrical engineering, an armature generally refers to one of the two principal electrical components of an electromechanical machine–generally in a motor or generator, but it may also mean the pole piece of a permanent magnet or electromagnet, or the moving iron part of a solenoid or relay....

 motors which drove the shafts directly and were much quieter, but this improvement was not universally fitted until the succeeding Tench class
Tench class submarine
Tench-class submarines were a type of submarine built for the United States Navy between 1944 and 1951. They were an evolutionary improvement over the Gato and Balao classes, only about 35 to 40 tons larger, but more strongly built and with a slightly improved internal layout...

. As the diesel engines were not directly connected to the shafts, the electric motors had to drive the shafts all the time.

The Balao class was successful, and one of its class brought down what remains the largest ship sunk by a submarine, the Japanese aircraft carrier Shinano
Japanese aircraft carrier Shinano
named after the ancient Shinano Province, was an aircraft carrier of the Imperial Japanese Navy during World War II. Initially laid down as the third of the battleships, Shinano′s partially complete hull was converted to an aircraft carrier in 1942, midway through construction. Over the next two...

 (59,000 tons).

Operational submarines

As of 2007 , a Balao-class submarine, was one of the last two operational submarines in the world built during World War II. It was transferred to the Republic of China
Republic of China
The Republic of China , commonly known as Taiwan , is a unitary sovereign state located in East Asia. Originally based in mainland China, the Republic of China currently governs the island of Taiwan , which forms over 99% of its current territory, as well as Penghu, Kinmen, Matsu and other minor...

 in the early 1970s.


Eight Balao-class submarines are open to public viewing. They primarily depend on revenue generated by visitors to keep them operational and up to U.S. Navy standards; each boat gets a yearly inspection and a "report card". Some boats, like Batfish and Pampanito, encourage youth functions and allow a group of volunteers to sleep overnight in the crew's quarters. The following is a complete list of Balao-class museum boats:
at War Memorial Park in Muskogee, Oklahoma
Muskogee, Oklahoma
Muskogee is a city in Muskogee County, Oklahoma, United States. It is the county seat of Muskogee County, and home to Bacone College. The population was 38,310 at the 2000 census, making it the eleventh-largest city in Oklahoma....

 at Independence Seaport Museum
Independence Seaport Museum
The Independence Seaport Museum is a museum dedicated to the maritime history of Philadelphia, Pennsylvania and the Delaware Valley. It is located in the Penn's Landing complex along the Delaware River in Philadelphia. The museum was founded in 1961 by J...

 in Philadelphia, Pennsylvania at USS Bowfin Submarine Museum & Park in Honolulu, Hawaii
Honolulu, Hawaii
Honolulu is the capital and the most populous city of the U.S. state of Hawaii. Honolulu is the southernmost major U.S. city. Although the name "Honolulu" refers to the urban area on the southeastern shore of the island of Oahu, the city and county government are consolidated as the City and...

 at Patriot's Point
Patriot's Point
Patriots Point Naval & Maritime Museum is located in Mount Pleasant, South Carolina, at the mouth of the Cooper River on the Charleston Harbor, across from Charleston.-Museum ships and exhibits:...

 in Mount Pleasant, South Carolina
Mount Pleasant, South Carolina
Mount Pleasant is a large affluent suburban town in Charleston County, South Carolina, United States. It is a member of the Charleston–North Charleston–Summerville Metropolitan Statistical Area, for statistical purpose only, as designated by the U.S. Office of Management and Budget....

 at New Jersey Naval Museum
New Jersey Naval Museum
The New Jersey Naval Museum , located along the Hackensack River in Hackensack, New Jersey, is dedicated to New Jersey's Navy heritage and naval history in general. The prominent element in the collection is the USS Ling , a long Balao-class submarine of World War II...

 in Hackensack, New Jersey
Hackensack, New Jersey
Hackensack is a city in Bergen County, New Jersey, United States and the county seat of Bergen County. Although informally called Hackensack, it was officially named New Barbadoes Township until 1921. As of the 2010 United States Census, the city population was 43,010....

 at Battleship Cove
Battleship Cove
Battleship Cove, located in Fall River, Massachusetts, is a nonprofit maritime museum and war memorial that traces its origins to the wartime crew of the World War II battleship . This dedicated veterans group was responsible for the donation of the decommissioned vessel from the Navy and its...

 in Fall River, Massachusetts
Fall River, Massachusetts
Fall River is a city in Bristol County, Massachusetts, in the United States. It is located about south of Boston, southeast of Providence, Rhode Island, and west of New Bedford and south of Taunton. The city's population was 88,857 during the 2010 census, making it the tenth largest city in...

 at San Francisco Maritime National Historical Park
San Francisco Maritime National Historical Park
The San Francisco Maritime National Historical Park is located in San Francisco, California, USA. The park includes a fleet of historic vessels, a visitor center, a maritime museum, and a library/research facility...

 in San Francisco, California
San Francisco, California
San Francisco , officially the City and County of San Francisco, is the financial, cultural, and transportation center of the San Francisco Bay Area, a region of 7.15 million people which includes San Jose and Oakland...

, which played the part of USS Stingray in the movie Down Periscope
Down Periscope
Down Periscope is a 1996 comedy film starring Kelsey Grammer as the captain of a rust-bucket Navy submarine, the USS Stingray, who is fighting for his career....

 at Arkansas Inland Maritime Museum
Arkansas Inland Maritime Museum
The Arkansas Inland Maritime Museum is a maritime museum located at 120 Riverfront Park Drive, North Little Rock, Arkansas which opened on May 15, 2005. Its primary exhibit is the , a World War Two which later served in the Korean, Vietnam and Cold Wars. The submarine was later transitioned to...

 in North Little Rock, Arkansas
North Little Rock, Arkansas
the city was 62.55% White, 33.98% Black or African American, 0.41% Native American, 0.59% Asian, 0.03% Pacific Islander, 1.18% from other races, and 1.26% from two or more races...

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.