USS Archerfish (SSN-678)
USS Archerfish, a Sturgeon-class attack submarine, was the second ship of the United States Navy to be named for the archerfish, a family of fish notable for their habit of preying on insects and other animals by shooting them down with squirts of water from the mouth. The contract to build Archerfish was awarded on 25 June 1968 and her keel was laid down on 19 June 1969 at Groton, Connecticut, by the Electric Boat Division of the General Dynamics Corporation, she was launched on 16 January 1971, sponsored by Miss Mary Conover Warner, commissioned at her home port, New London, Connecticut, on 17 December 1971 with Commander Ralph Gordon Bird in command. Following her commissioning, Archerfish proceeded to Newport, Rhode Island, in late January 1972 and to the Caribbean Sea for shakedown training, she held acoustic sea trials in Exuma Sound in the Bahama Islands and weapons systems acceptance trials at Roosevelt Roads off Puerto Rico, at St. Croix in the United States Virgin Islands, she carried out tests off the Bahamas in April and May 1972.
From 5 to 15 June 1972, Archerfish participated in North Atlantic Treaty Organization Exercise "Pink Lace" in the mid-Atlantic Ocean. In August 1972, she took part in Antisubmarine Warfare Exercise 1–73. On 5 September 1972, she began post-shakedown repairs and alterations in the Electric Boat Division shipyard at Groton, where she received extensive modifications and new equipment, she left the shipyard on 26 October and spent the rest of 1972 in local operations and preparation for her first overseas deployment. On 6 January 1973, Archerfish shaped a course for the Mediterranean Sea. During her deployment there, she conducted two special operations and visited Rota and Naples, Italy, her deployment concluded with her arrival at Naval Submarine Base New London, Connecticut, on 19 June 1973. Archerfish got underway again in August 1973, bound for the Bahama Islands to participate in Atlantic Submarine Exercise KILO 1–74, she provided services in support of a special project under the direction of the Chief of Naval Operations in the western Atlantic Ocean during the last half of September 1973.
She traveled to a testing range off the Bahamas, held torpedo certification trials, arrived at New London on 12 October 1973 for extensive training in preparation for her second overseas deployment. Archerfish left New London on 7 January 1974 for special operations in the North Atlantic Ocean. During this cruise, she visited Faslane Naval Base, before returning to New London on 8 March 1974. Following upkeep, she voyaged to the Narragansett Bay in early May 1974 to carry out sonar evaluation projects. On 27 May 1974, she proceeded to Port Everglades, for further testing, she continued on to the Caribbean to take part in Atlantic Submarine Exercise KILO 2–74 near the Bahamas. On 10 June 1974, Archerfish arrived at New London and began testing and evaluating new sonar equipment. Archerfish departed New London for the Bahamas once again on 9 September 1974 to participate in Atlantic Submarine Exercise KILO 1–75. Upon its completion she took part in naval mine testing near Port Everglades, she returned to the Caribbean on 30 October 1974 for torpedo proficiency firings.
From 5 November to 18 November 1974, she participated in Submarine Antisubmarine Warfare Exercise 1–75 and returned to New London for a period of leave and upkeep. In February and March 1975, Archerfish carried out special operations in the western Atlantic Ocean, she took part in Operation Agate Punch, which involved the development and utilization of tactics in direct support of other ships of the United States Atlantic Fleet, from 14 April to 28 April 1975. During the summer months of 1975, Archerfish carried out a deployment in the western Atlantic Ocean, which included a port call at Halifax, Nova Scotia, Canada. In November and December 1975, she was involved in two additional tactical development exercises, RANGEX 2–76 and SECEX 3–75, she conducted torpedo tests. After a period of holiday leave and upkeep and the end of 1975 and beginning of 1976, Archerfish took part in Submarine Antisubmarine Warfare Exercise 1–76 in February 1976 before commencing a deployment to the North Atlantic Ocean in March 1976.
During April and May 1976, she carried out independent operations and returned to New London in June. She moved to Portsmouth, where she began overhaul at the Norfolk Naval Shipyard on 7 July 1976. During her post-overhaul sea trials in May 1977, Archerfish's home port was changed from New London to Naval Station Norfolk at Norfolk, Virginia, on 12 May 1977. Archerfish began post-overhaul shakedown on 8 June 1977, she held torpedo proficiency firings and made port visits at Port Everglades and Port Canaveral, Florida. She began upkeep. Archerfish got underway again on 21 August 1977 for a cruise during which she hosted a class of prospective commanding officers, she carried out torpedo tests and made a stop at Port Everglades. Archerfish arrived at Norfolk on 6 September 1977, but put to sea again on 12 September, bound for the West Indies to conduct torpedo test firings off the Bahamas and to perform special sonar tests in the Atlantic Ocean. Upon returning to Norfolk on 28 September 1977, Archerfish began preparations for an overseas deployment in the Mediterranean.
She left Norfolk on 12 December 1977 crossed the Atlantic, spent the Christmas holidays in port at Lisbon and entered the Mediterranean Sea on 28 December 1977. While operating with the United States Sixth Fleet in the Mediterranean, she participated in Chief of Naval Operation Project "Over the Horizon Testing" and, during March 1978 took part in Exercise "Dogfish." She concluded her deployment with her arrival at Norfolk in May
Ingalls Shipbuilding is a shipyard located in Pascagoula, United States established in 1938, now part of Huntington Ingalls Industries. It is a leading producer of ships for the United States Navy, at 12,500 employees, the second largest private employer in Mississippi with WalMart being the largest with 24,000 employees. In 1938, Ingalls Shipbuilding Corporation was founded by Robert Ingersoll Ingalls, Sr. of Birmingham, Alabama, on the East Bank of the Pascagoula River in Mississippi. Ingalls was located, it started out building commercial ships including the USS George Clymer, which took part in Liberty Fleet Day 27 September 1941. In the 1950s Ingalls started bidding on Navy work, winning a contract in 1957 to build 12 nuclear-powered attack submarines. Litton Industries acquired Ingalls in 1961, in 1968 expanded its facilities to the other side of the river. Ingalls reached a high point of employment with 27,280 workers. In April 2001, Litton was acquired by the Northrop Grumman Corporation.
On 29 August 2005, Ingalls facilities were damaged by Hurricane Katrina. While shipbuilding was halted for a while due to the destruction of many buildings, most vehicles and the large overhead cranes are the same that the facility continues to operate today. On 31 March 2011, Northrop Grumman spun off its shipbuilding sector into a new corporation, Huntington Ingalls Industries. In 2015, Ingalls Shipbuilding Company signed a contract with US Navy for new destroyers, littoral combat ships, new landing craft. USS John Finn was one of the first new destroyers and was launched on March 28; the company is building the USS Ralph Johnson, USS Paul Ignatius and USS Delbert D. Black. On 21 March 2015, the new San Antonio-class amphibious transport dock ship USS John P. Murtha was ceremonially christened; the vessel had been launched on October 30 and was commissioned in 2017. On 27 March 2015, the shipyard received construction contracts for their next destroyers. Ingalls Shipbuilding Company was awarded a $604.3 million contract modification to build the USS Frank E. Petersen Jr..
On 31 March 2015, the shipyard received another contract with a $500 million fixed price to build the eighth National Security Cutter for the US Coast Guard. Most of them will be under construction until 2019; the cutters are the most advanced ships built for the Coast Guard. On 30 June 2016, Ingalls Shipbuilding signed a contract with US Navy to build the U. S. Navy's next large-deck amphibious assault warship; the contract included planning, advanced engineering, procurement of long-lead material, is just over $272 million. If options are exercised, the cumulative value of the contract would be $3.1 billion Ingalls' primary product has been naval ships, naval projects for Egypt and Venezuela. In the 1950s, Ingalls attempted to enter the diesel locomotive market, they cataloged an extensive product line, but only one example, known as the model 4-S, was produced. It was sold to the Mobile & Ohio Railroad. Ingalls manufactured covered hopper railroad cars in the early 1980s, producing around 4,000 units for the lease market via North American Car.
Ships built by Ingalls include: Barbel class: USS Blueback Skipjack class: USS Sculpin USS Snook Thresher/Permit class: USS Barb USS Dace USS Haddock Sturgeon class: USS Tautog USS Pogy USS Aspro USS Puffer USS William H. Bates USS Tunny USS Parche Spruance class: USS Spruance USS Paul F. Foster USS Kinkaid USS Hewitt USS Elliot USS Arthur W. Radford USS Peterson USS Caron USS David R. Ray USS Oldendorf USS John Young USS Comte de Grasse USS O'Brien USS Merrill USS Briscoe USS Stump USS Conolly USS Moosbrugger USS John Hancock USS Nicholson USS John Rodgers USS Leftwich USS Cushing USS Harry W. Hill USS O'Bannon USS Thorn USS Deyo USS Ingersoll USS Fife USS Fletcher USS Hayler Kidd class: USS Kidd USS Callaghan USS Scott USS Chandler Arleigh Burke class:USS Barry USS Stout USS Mitscher USS Russell USS Ramage USS Stethem USS Benfold USS Cole USS Milius USS Ross USS McFaul USS Porter USS Roosevelt USS Lassen USS Bulkeley USS Shoup USS Preble USS Mustin USS Pinckney USS Chung-Hoon USS James E. Williams USS Halsey USS Forrest Sherman USS Kidd USS Truxtun USS Dewey USS Gravely USS William P. Lawrence USS John Finn USS Ralph Johnson USS Paul Ignatius USS Delbert D. Black USS Frank E. Petersen Jr. Ticonderoga class: USS Ticonderoga USS Yorktown USS Vincennes USS Bunker Hill USS Mobile Bay USS Antietam USS Leyte Gulf USS San Jacinto USS Lake Champlain USS Princeton USS Chancellorsville USS Chosin USS Hué City USS Anzio USS Vicksburg USS Cape St. George USS Vella Gulf USS Port Royal Legend class: USCGC Bertholf USCGC Waesche USCGC Stratton U
United States Navy SEALs
The United States Navy Sea and Land Teams abbreviated as Navy SEALs, are the U. S. Navy's a component of the Naval Special Warfare Command. Among the SEALs' main functions are conducting small-unit maritime military operations that originate from, return to, a river, swamp, delta, or coastline; the SEALs are trained to operate in all environments. As of 2017, all active SEALs are male and members of the U. S. Navy; the CIA's secretive and elite Special Operations Group recruits operators from SEAL Teams, with joint operations going back to the MACV-SOG during the Vietnam War. This cooperation still exists today, as evidenced by military operations in Afghanistan; the modern day U. S. Navy SEALs can trace their roots to World War II; the United States Navy recognized the need for the covert reconnaissance of landing beaches and coastal defenses. As a result, the Amphibious Scout and Raider School was established in 1942 at Florida; the Scouts and Raiders were formed in September of that year, just nine months after the attack on Pearl Harbor, from the Observer Group, a joint U.
S. Army-Marine-Navy unit. Recognizing the need for a beach reconnaissance force, a select group of Army and Navy personnel assembled at Amphibious Training Base Little Creek, Virginia on August 15, 1942 to begin Amphibious Scouts and Raiders training; the Scouts and Raiders mission was to identify and reconnoiter the objective beach, maintain a position on the designated beach prior to a landing, guide the assault waves to the landing beach. The first group included Phil H. Bucklew, the "Father of Naval Special Warfare," after whom the Naval Special Warfare Center building is named. Commissioned in October 1942, this group saw combat in November 1942 during Operation Torch on the North African Coast. Scouts and Raiders supported landings in Sicily, Anzio and southern France. A second group of Scouts and Raiders, code-named Special Service Unit No. 1, was established on 7 July 1943, as a combined operations force. The first mission, in September 1943, was at Finschhafen in Papua New Guinea. Operations were at Gasmata, Cape Gloucester, the east and south coasts of New Britain, all without any loss of personnel.
Conflicts arose over operational matters, all non-Navy personnel were reassigned. The unit, renamed 7th Amphibious Scouts, received a new mission, to go ashore with the assault boats, buoy channels, erect markers for the incoming craft, handle casualties, take offshore soundings, clear beach obstacles and maintain voice communications linking the troops ashore, incoming boats and nearby ships; the 7th Amphibious Scouts conducted operations in the Pacific for the duration of the conflict, participating in more than 40 landings. The third and final Scouts and Raiders organization operated in China. Scouts and Raiders were deployed to fight with the Sino-American Cooperative Organization, or SACO. To help bolster the work of SACO, Admiral Ernest J. King ordered that 120 officers and 900 men be trained for "Amphibious Raider" at the Scout and Raider school at Fort Pierce, Florida, they formed the core of what was envisioned as a "guerrilla amphibious organization of Americans and Chinese operating from coastal waters and rivers employing small steamboats and sampans."
While most Amphibious Raider forces remained at Camp Knox in Calcutta, three of the groups saw active service. They conducted a survey of the upper Yangtze River in the spring of 1945 and, disguised as coolies, conducted a detailed three-month survey of the Chinese coast from Shanghai to Kitchioh Wan, near Hong Kong. In September 1942, 17 Navy salvage personnel arrived at ATB Little Creek, Virginia for a week long course in demolitions, explosive cable cutting and commando raiding techniques. On November 10, 1942, the first combat demolition unit cut cable and net barriers across the Wadi Sebou River during Operation Torch in North Africa; this enabled USS Dallas to traverse the water and insert U. S. Rangers who captured the Port Lyautey airdrome. In early May 1943, a two-phase "Naval Demolition Project" was directed by the Chief of Naval Operations "to meet a present and urgent requirement"; the first phase began at Amphibious Training Base Solomons, Maryland with the establishment of Operational Naval Demolition Unit No. 1.
Six officers and eighteen enlisted men reported from the Seabee's NTC Camp Peary dynamiting and demolition school, for a four-week course. Those Seabees, lead by Lieutenant Fred Wise CEC, were sent to participate in the invasion of Sicily. At that time Lieutenant Commander Draper L. Kauffman, "The Father of Naval Combat Demolition," was selected to set up a school for Naval Demolitions and direct the entire Project; the first six classes graduated from "Area E" at NTC Camp Peary. LCDR Kauffman's needs out-grew "Area E" and on 6 June 1943 he established NCDU training at Fort Pierce. Most of Kauffman's volunteers enlisted seabees. Training commenced with a gruelling week designed to filter out under-performing candidates. By April 1944, a total of 34 NCDUs were deployed to England in preparation for Operation Overlord, the amphibious landing at Normandy. On 6 June 1944, under heavy five, the NCDUs at Omaha Beach managed to blow eight complete gaps and two partial gaps in the German defenses; the NCDUs suffered 31 killed and 60 wounded, a casualty rate of 52%.
Meanwhile, the NCDUs at Utah Beach met less intense enemy fire. They cleared 700 yards of beach another 900 yards by the afternoon. Casualties at Utah Beach were lighter with six killed and eleven wounded. During Oper
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. Turbo-electric drives are used in some rail ships. An advantage of turbo-electric transmission is that it allows the adaptation of high-speed turning turbines to the turning propellers or wheels without the need of a heavy and complex gearbox, it has the advantage of being able to provide electricity for the ship or train's other electrical systems, such as lighting, computers and communications equipment. Colorado-class USS New Mexico Tennessee-class USS Langley Lexington-class Buckley-class Rudderow-class Admiral W. S. Benson-class transports Gilliam-class attack transports USS Glenard P. Lipscomb USS Tullibee Triomphant-class submarines Columbia-class submarines Suamico-class oilers Tampa-class cutters USCGC Haida, USCGC Modoc, USCGC Mojave and USCGC Tampa. California and Virginia Canberra – the most powerful steam turbo-electric units in a passenger ship, 42,500 shp per shaft, 2 shafts RMS Mooltan Morro Castle and Oriente Normandie – most powerful steam turbo-electric passenger ship 40,000 shp per shaft, 4 shafts Potsdam and Scharnhorst President Cleveland and President Wilson President Hoover and President Coolidge RMS Queen Mary 2 – powered by General Electric gas turbines as well as her diesel generators to generate the current for her four Rolls-Royce electric podded azimuth thrusters Santa Clara Strath-class ocean liners RMS Strathnaver and RMS Strathaird RMS Viceroy of India Cuba, converted to turbo-electric transmission in 1920 Princess Marguerite and Princess Patricia TEV Wahine TEV Rangatira – the World's last steam-powered turbo-electric merchant ship.
"Turboelectric drive in American Capital Ships". The Naval Technical Board. NavWeaps. Draper, John L. "The Paddle Wheel to Electric Drive". Popular Mechanics: 898–902. — detailed article with drawing and charts on turbo-electric drive for ships and the advantages
Nuclear marine propulsion
Nuclear marine propulsion is propulsion of a ship or submarine with heat provided by a nuclear power plant. The power plant heats water to produce steam for a turbine used to turn the ship's propeller through a gearbox or through an electric generator and motor. Naval nuclear propulsion is used within naval warships such as supercarriers. A small number of experimental civil nuclear ships have been built. Compared to oil or coal fuelled ships, nuclear propulsion offers the advantages of long intervals of operation before refueling. All the fuel is contained within the nuclear reactor, so no cargo or supplies space is taken up by fuel, nor is space taken up by exhaust stacks or combustion air intakes. However, the low fuel cost is offset by the high operating costs and investment in infrastructure, so nearly all nuclear-powered vessels are military ones. Naval reactors are of the pressurized water type. A primary water circuit transfers heat generated from nuclear fission in the fuel to a steam generator.
This circuit operates at a temperature of around 250 to 300 °C. Any radioactive contamination in the primary water is confined. Water is circulated by pumps; the hot water from the reactor heats a separate water circuit in the steam generator. The water passes through steam driers on its way to the steam turbine. Spent steam at low pressure is run through a condenser cooled by seawater and returns to liquid form; the water continues the cycle. Any water lost in the process can be made up by desalinated sea water added to the steam generator feed water. In the turbine, the steam expands and reduces its pressure as it imparts energy to the rotating blades of the turbine. There may be many stages of fixed guide vanes; the output shaft of the turbine may be connected to a gearbox to reduce rotation speed a shaft connects to the vessel's propellers. In another form of drive system, the turbine turns an electrical generator, the electric power produced is fed to one or more drive motors for the vessel's propellers.
The Russian, US and British navies rely on direct steam turbine propulsion, while the French and Chinese ships use the turbine to generate electricity for propulsion. Most nuclear submarines have a single reactor, but Russian submarines have two, so had USS Triton. Most American aircraft carriers are powered by two reactors; the majority of marine reactors are of the pressurized water type, although the US and Soviet navies have designed warships powered with liquid metal cooled reactors. Marine-type reactors differ from land-based commercial electric power reactors in several respects. While land-based reactors in nuclear power plants produce up to around 1600 megawatts of electrical power, a typical marine propulsion reactor produces no more than a few hundred megawatts. Space considerations dictate that a marine reactor must be physically small, so it must generate higher power per unit of space; this means. Its mechanical systems must operate flawlessly under the adverse conditions encountered at sea, including vibration and the pitching and rolling of a ship operating in rough seas.
Reactor shutdown mechanisms cannot rely on gravity to drop control rods into place as in a land-based reactor that always remains upright. Salt water corrosion is an additional problem; as the core of a seagoing reactor is much smaller than a power reactor, the probability of a neutron intersecting with a fissionable nucleus before it escapes into the shielding is much lower. As such, the fuel is more enriched than that used in a land-based nuclear power plant, which increases the probability of fission to the level where a sustained reaction can occur; some marine reactors run on low-enriched uranium which requires more frequent refueling. Others run on enriched uranium, varying from 20% 235U, to the over 96% 235U found in U. S. submarines, in which the resulting smaller core is quieter in operation. Using more-highly enriched fuel increases the reactor's power density and extends the usable life of the nuclear fuel load, but is more expensive and a greater risk to nuclear proliferation than less-highly enriched fuel.
A marine nuclear propulsion plant must be designed to be reliable and self-sufficient, requiring minimal maintenance and repairs, which might have to be undertaken many thousands of miles from its home port. One of the technical difficulties in designing fuel elements for a seagoing nuclear reactor is the creation of fuel elements which will withstand a large amount of radiation damage. Fuel elements may crack over time and gas bubbles may form; the fuel used in marine reactors is a metal-zirconium alloy rather than the ceramic UO2 used in land-based reactors. Marine reactors are designed for long core life, enabled by the high enrichment of the uranium and by incorporating a "burnable poison" in the fuel elements, depleted as the fuel elements age and become less reactive; the gradual dissipation of the "nuclear poison" increases the reactivity of the core to compensate for the lessening reactivity of the aging fuel elements, thereby lengthening the usable life of the fuel. The life of the compact reactor pressure vessel is extended by providing an internal neutron shield, which reduces the
Newport News Shipbuilding
Newport News Shipbuilding, a division of Huntington Ingalls Industries, is the largest industrial employer in Virginia, sole designer and refueler of United States Navy aircraft carriers and one of two providers of U. S. Navy submarines. Founded as the Chesapeake Dry Dock and Construction Co. in 1886, Newport News Shipbuilding has built more than 800 ships, including both naval and commercial ships. Located in the city of Newport News, their facilities span more than 550 acres, strategically positioned in one of the great harbors of the East Coast; the shipyard is a major employer, not only for the lower Virginia Peninsula, but portions of Hampton Roads south of the James River and the harbor, portions of the Middle Peninsula region, some northeastern counties of North Carolina. The shipyard is building USS Enterprise. In 2013, Newport News Shipbuilding began the deactivation of the first nuclear-powered aircraft carrier, USS Enterprise, which it built. Newport News Shipbuilding performs refueling and complex overhaul work on Nimitz-class aircraft carriers.
This is a four-year vessel renewal program that not only involves refueling of the vessel's nuclear reactors but includes modernization work. The yard has completed RCOH for four Nimitz-class carriers; as of May 2016 this work was underway for USS Abraham Lincoln. As of November 2017 this work was underway for USS George Washington. Industrialist Collis P. Huntington provided crucial funding to complete the Chesapeake and Ohio Railroad from Richmond, Virginia to the Ohio River in the early 1870s. Although built for general commerce, this C&O rail link to the midwest was soon being used to transport bituminous coal from the isolated coalfields, adjacent to the New River and the Kanawha River in West Virginia. In 1881, the Peninsula Extension of the C&O was built from Richmond down the Virginia Peninsula to reach a new coal pier on Hampton Roads in Warwick County near the small unincorporated community of Newport News Point. However, building the railroad and coal pier was only the first part of Huntington's dreams for Newport News.
In 1886, Huntington built a shipyard to repair ships servicing this transportation hub. In 1891 Newport News Shipbuilding and Drydock Company delivered its first ship, the tugboat Dorothy. By 1897 NNS had built three warships for the US Navy: USS Nashville and Helena; when Collis died in 1900, his nephew Henry E. Huntington inherited much of his uncle's fortune, he married Collis' widow Arabella Huntington, assumed Collis' leadership role with Newport News Shipbuilding and Drydock Company. Under Henry Huntington's leadership, growth continued. In 1906 the revolutionary HMS Dreadnought launched a great naval race worldwide. Between 1907 and 1923, Newport News built six of the US Navy's total of 22 dreadnoughts – USS Delaware, Pennsylvania, Mississippi and West Virginia. All but the first were in active service in World War II. In 1907 President Theodore Roosevelt sent the Great White Fleet on its round-the-world voyage. NNS had built seven of its 16 battleships. In 1914 NNS built SS Medina for the Mallory Steamship Company.
In the early years, leaders of the Newport News community and those of the shipyard were interchangeable. Shipyard president Walter A. Post served from March 1911 to February 12, 1912, when he died. Earlier, he had come to the area as one of the builders of the C&O Railway's terminals, had served as the first mayor of Newport News after it became an independent city in 1896, it was on March 14, 1914 that Albert Lloyd Hopkins, a young New Yorker trained in engineering, succeeded Post as president of the company. In May 1915 while traveling to England on shipyard business aboard RMS Lusitania, Albert L. Hopkins tenure and life ended prematurely when that ship was torpedoed and sunk by a German U-boat off Queenstown on the Irish coast, his assistant, Frederic Gauntlett, was on board, but was able to swim to safety. Homer Lenoir Ferguson was company vice president when Hopkins died, assumed the presidency the following August, he saw the company through both world wars, became a noted community leader, was a co-founder of the Mariners' Museum with Archer Huntington.
He served until July 1946, after World War II had ended on both the European and Pacific fronts. Just northwest of the shipyard, Hilton Village, one of the first planned communities in the country, was built by the federal government to house shipyard workers in 1918; the planners met with the wives of shipyard workers. Based on their input 14 house plans were designed for the projected 500 English-village-style homes. After the war, in 1922, Henry Huntington acquired it from the government, helped facilitate the sale of the homes to shipyard employees and other local residents. Three streets there were named after Post and Ferguson; the Lusitania incident was among the events that brought the United States into World War I. Between 1918 and 1920 NNS delivered 25 destroyers, after the war it began building aircraft carriers. USS Ranger was delivered in 1934, NNS went on to build Yorktown and Enterprise. After World War I NNS completed a major reconditioning and refurbishment of the ocean liner SS Leviathan.
Before the war she had been the German liner Vaterland, but the start of hostilities found her laid up in New York Harbor and she had been seized by the US Government in 1917 and converted into a troopship. War duty and age meant
Mark 37 torpedo
The Mark 37 torpedo is a torpedo with electrical propulsion, developed for the US Navy after World War II. It entered service with the US Navy with over 3,300 produced, it was phased out of service with the US Navy during the 1970s, the stockpiles were sold to foreign navies. Its engineering development began in 1946 by Westinghouse-ORL, it was based on the active homing system tested on modified Mark 18s, with added passive homing and a new torpedo body. Between 1955-56, thirty torpedoes were produced for development testing, with large-scale production commenced shortly afterwards. Due to its electric propulsion, the torpedo swam smoothly out of the launch tube, instead of having to be ejected by pressurized air, therefore reducing its acoustic launch signature. To allow for water flow around the torpedo while swimming out, several 1" thick guide studs were attached to the torpedo, which although 19" in diameter was designed to be used only from 21" torpedo tubes; the guidance of a Mk37 mod 0 torpedo was done by a gyroscope control during the initial part of its trajectory, where the gyro control achieved a straight run, a passive sonar homing system, at the last 700 yards by a Doppler-enabled active sonar homing, with magnetostrictive transducers operating at 60 kHz.
The electronics was based on miniature vacuum tubes on solid-state semiconductor devices. The mod 1 torpedoes were longer and heavier than mod 0, but offered better target acquisition capabilities and higher ability to intercept agile submarines, they used wire-guidance. The efficiency of Mk37 torpedoes was high for targets with speed lower than 20 knots and depth less than 1,000 ft; as submarines with higher speeds and operating depths appeared, new torpedoes were developed. Of them, NT37C, D, E, F are based on the Mk37 design. In 1967, the mod 0s started being refurbished as mod 3, mod 1 as mod 2; these modifications involved many changes including replacement of magneto-constrictive transducers with piezoelectric ones, resulted in target acquisition range increased from 700 yd to 1,000 yd without loss of sensitivity with increasing depth. The torpedoes used Mark 46 silver-zinc batteries; these had a known tendency to overheat igniting or exploding. Training torpedoes used reusable rechargeable secondary batteries.
For a long time, the Mark 37 was a primary U. S. submarine-launched ASW torpedo. It was replaced by the Mark 48 starting in 1972; the remaining inventory was rebuilt and sold to several countries, including Israel, as the NT-37C after the vacuum tube guidance systems were replaced by solid-state electronics and the electric propulsion was replaced with a liquid monopropellant. The Mk 67 submarine launched, it entered service in 1983 and is capable of swimming as far as 10 miles through or into a channel, shallow water area and other zones which would be inaccessible to the vessel laying it. After reaching the target area it sinks to the sea bed and acts like a conventionally laid influence mine; the exploder in the Mk 67 warhead is computerised and incorporates magnetic and pressure sensors. Power plant: Mark 46 silver-zinc battery, two-speed electric motor Length: 135 inches, 161 inches Weight: 1,430 pounds, 1,660 pounds Diameter: 19 inches Range: 23,000 yards at 17 knots, 10,000 yards at 26 knots Depth: 1,000 feet Speed: 17 knots, 26 knots Guidance system: active/passive sonar homing.
S. Navy's First Active Acoustic Homing Torpedoes