Submarines in the United States Navy

There are three major types of submarines in the United States Navy: ballistic missile submarines, attack submarines, and cruise missile submarines. All submarines currently in the U.S. Navy are nuclear-powered. Ballistic missile submarines have a single strategic mission of carrying nuclear submarine-launched ballistic missiles. Attack submarines have several tactical missions, including sinking ships and subs, launching cruise missiles, and gathering intelligence. Cruise missile submarines perform many of the same missions as attack submarines, but with a focus on their ability to carry and launch larger quantities of cruise missiles than typical attack submarines.
The submarine has a long history in the United States, beginning with the Turtle, the world's first submersible with a documented record of use in combat.

History

Early history (1775–1914)

The first submarine used in combat was the USS Turtle. The Turtle was built in 1775 and was made to attach explosive charges to the hulls of the ships. Several attempts were made against British ships in American harbors in 1776, but none were successful.
Other submersible projects date to the 19th century. Alligator was a US Navy submarine that was never commissioned. She was being towed to South Carolina to be used in taking Charleston, but was lost in bad weather on 2 April 1863 off Cape Hatteras, North Carolina. On February 17, 1864, the H. L. Hunley became the first submarine to sink a warship.
Real progress began late in the century with the building of the, named after John Philip Holland. The USS Holland was the first submarine in the US Navy, commissioned on April 1, 1900. Submarines have been active component of the US Navy ever since. The boat was developed at Lewis Nixon's Crescent Shipyard located in Elizabeth, New Jersey. This pioneering craft was in service for 10 years and was a developmental and trials vessel for many systems on other early submarines.
Later submarines were given such names as Grampus, Salmon, and Porpoise, but were also named for venomous and stinging creatures, such as Adder, Tarantula, and Viper. Submarines were renamed in 1911 and carried alphanumeric names such as A-1, C-1, H-3, and L-7. In 1920 the U.S. Navy Department established a standard Type and Class letter designation system. "SS" was established as the two-letter class designation for Submarine. In addition to a name, each U.S. submarine carries a Class designation followed by an assigned hull number. Note that "SS" is not an acronym for 'Submersible Ship'; Warship classifications for U.S. submarines include "SSN", Submarine ; "SSBN", Ballistic Missile Submarine, and "SSGN", Guided Missile Submarine.

World War I and the inter-war years (1914–1941)

The submarine truly came of age in World War I. The US Navy did not have a large part in this war, with action mainly being confined to escorting convoys later in the war and sending a division of battleships to reinforce the British Grand Fleet. However, there were those in the submarine service who saw what the Germans had done with their U-boats and took careful note.

World War II (1941–1945)

Doctrine in the inter-war years emphasized the submarine as a scout for the battle fleet, and also extreme caution in command. Both these axioms were proven wrong after the attack on Pearl Harbor in December 1941. The submarine skippers of the fleet boats of World War II waged a very effective campaign against Japanese merchant vessels, eventually repeating and surpassing Germany's initial success during the Battle of the Atlantic against the United Kingdom.

Offensive against Japanese ships

Date	Additions	Losses	Net change	End of period total	Index
12 July 1941				6,384,000	100
12/1941	44,200	51,600	−7,400	6,376,600	99
1942	661,800	1,095,800	−434,000	5,942,600	93
1943	1,067,100	2,065,700	−998,600	4,494,400	77
1944	1,735,100	4,115,100	−2,380,000	2,564,000	40
1/45 – 8/45	465,000	1,562,100	−1,097,100	1,466,900	23

During the war, submarines of the United States Navy were responsible for 55% of Japan's merchant marine losses; other Allied navies added to the toll. The war against shipping was the single most decisive factor in the collapse of the Japanese economy.
The Navy adopted an official policy of unrestricted submarine warfare, and it appears the policy was executed without the knowledge or prior consent of the government. The London Naval Treaty, to which the U.S. was signatory, required submarines to abide by prize rules. It did not prohibit arming merchantmen, but arming them, or having them report contact with submarines, made them de facto naval auxiliaries and removed the protection of the cruiser rules. This made restrictions on submarines effectively moot. U.S. Navy submarines also conducted reconnaissance patrols, landed special forces and guerrilla troops and performed search and rescue tasks.
In addition to sinking Japanese merchant ships, postwar records compiled by the Joint Army-Navy Assessment Committee indicate Japan lost 686 warships of 500 gross tons or larger to submarines during 1,600 war patrols. Only 1.6 percent of the total U.S. naval manpower was responsible for America's success on its Pacific high seas; more than half of the total tonnage sunk was credited to U.S. submarines. The tremendous accomplishments of American submarines were achieved at the expense of 52 subs with 374 officers and 3,131 enlisted volunteers lost during combat against Japan; Japan lost 128 submarines during the Second World War in Pacific waters. American casualty counts represent 16 percent of the U.S. operational submarine officer corps and 13 percent of its enlisted force.

Lifeguard League

In addition to their commerce raiding role, submarines also proved valuable in air-sea rescue. While in command of United States Navy aircraft carrier Task Group 50.1 Rear Admiral Charles Alan Pownall, proposed to Admiral Charles A. Lockwood, Commander, Submarine Force, Pacific Fleet that submarines be stationed near targeted islands during aerial attacks. In what became known as the "Lifeboat League", pilots were informed that they could ditch their damaged planes near these submarines and be rescued by them. Eventually the rescue of downed American pilots became the second most important submarine mission after the destruction of Japanese shipping. Initially, the rescue submarines met several obstacles, most important of which was the lack of communication between the submarines and aircraft in the area; this led to several Lifeguard League submarines being bombed or strafed, possibly including the sinking of and by American planes.

Year	Days on Lifeguard station	Number of rescues
1943	64	7
1944	469	117
1945	2739	380
Total	3272	504

As the Pacific War continued, the eventual creation of Standing Operating Procedure led to several improvements such as the assignment of nearby submarines before air attacks, and the institution of reference points to allow pilots to report their location in the clear.
After the capture of the Marianas, targets such as Tokyo, about 1,500 mi north of the Marianas, were brought within range of B-29 attacks and Lifeguard League submarines began rescue operations along their flight paths.
Submarine lifeguards spent a combined 3,272 days on rescue duty and rescued 502 men. Famous examples include the rescue of 22 airmen by the, and the rescue of future U.S. President George H. W. Bush by the.

Cold War (1945–1991)

After WWII, things continued along much the same path until the early 1950s. Then, a revolution that was to forever change the nature of the submarine arm occurred. That revolution was.

Towards the "Nuclear Navy"

The was the first nuclear-powered submarine. Nautilus put to sea for the first time on 17 January 1955, transmitting the historic message, "Under way on nuclear power." Up until that point, submarines had been torpedo boats tied to the surface by the need to charge their batteries using diesel engines relatively often. The nuclear power plant of the Nautilus meant that the boat could stay underwater for literally months at a time, the only operational limit being the amount of food that the boat could carry. With resupply by mini-subs, even this could be overcome. The final limits would be for replacing equipment that wears out, the fatigue limit of the hull, and crew morale.

Strategic deterrence

Another revolution in submarine warfare came with. Nuclear-powered like, the George Washington added strategic ballistic missiles making the nuclear triad. Earlier Regulus missile submarines were diesel powered. Their cruise missiles required the boat to surface in order to fire, and were vulnerable to air defenses in an era when there were no anti-ballistic missiles.
George Washingtons missiles could be fired while the boat was submerged, meaning that it was far less likely to be detected before firing. The nuclear power of the boat also meant that, like Nautilus, George Washingtons patrol length was limited only by the amount of food the boat could carry. Ballistic missile submarines, carrying Polaris missiles, eventually superseded all other strategic nuclear systems in the Navy. Deterrent patrols continue to this day, although now with s and Trident II missiles.
The United States lost two nuclear submarines during the Cold War: due to equipment failure during a test dive while at its operational limit, and due to unknown causes.