How Does a Submarine Work?

Deep sea submarines are ships that can operate underwater. There are many types of submarines, with different shapes, ranging from small-scale civilian submersible detectors that are fully automatic or operated by one or two people and operate for hours, as large as Russian typhoon-class nuclear submarines that can carry hundreds of people and submarine for 3-6 months. . According to volume, it can be divided into large (mainly military), medium or small (pocket submarine, submersible) and underwater automatic mechanical devices. ^[1]

Deep sea submarines, deep dives are ships that can operate underwater. There are many types of submarines, with different shapes, ranging from small-scale civilian submersible detectors that are fully automatic or operated by one or two people and operate for hours, as large as Russian typhoon-class nuclear submarines that can carry hundreds of people and submarine for 3-6 months. . According to volume, it can be divided into large (mainly military), medium or small (pocket submarine, submersible) and underwater automatic mechanical devices.

Large submarines are mostly cylindrical, and a vertical structure (bridge) is usually set up in the middle of the ship. In the early days, it was called a "conning tower." Professional submarines often do not have this design.

Since the First World War, submarines have been widely used, and have served as important positions for many large navies. Their functions include attacking enemy warships or submarines, coastal protection, breaking through blockades, reconnaissance, and concealing special forces operations. Submarines are also used for non-military purposes, such as marine scientific research, rescue of property, exploration and mining, scientific detection, maintenance equipment, search and rescue, submarine cable repair, underwater tourism, academic surveys, etc., and the super-rich are even used underwater. Mobile mansion.

Submarines are recognized as strategic weapons (especially in negotiations for disarmament or expansion), and their research and development require high and comprehensive industrial capabilities. Currently only a few countries can design and produce them on their own. ^[1]

All boats on the water, including submarines after floating, must be subjected to positive buoyancy greater than gravity. So if you want to dive, the submarine must get more negative buoyancy, which means that the submarine either has its own gravity greater than its buoyancy, or reduces its displacement. As for the control of the displacement (volume of drainage), the control of gravity can be completely controlled by equipping a water tank called a "sink and float tank". That is to change the gravity of the submarine by controlling the water injection in the submersible tank.

For ordinary descent and floating actions, submarines usually use two front and rear submersible tanks. These two submersible tanks are also called the main submersible tank or the main ballast tank (MBT). When the submarine needs to dive, the main submersible tank water port is fully opened and filled with water to increase the submarine's gravity. When the submarine needs to rise, the main submersible tank water port is opened again and at the same time compressed air is injected into the main submersible tank to discharge. The water in the tank reduces gravity. The main submersible tank is mainly responsible for large submarine submergence. The water tank is usually placed below the floating waterline. If you need more precise control of the submarine's depth, you need to use a depth control tank or a hard water tank , Referred to as DCT, or hard tank). They are called "hard water tanks" mainly because they have to withstand greater pressure than the main water tank. Depth control The amount of water in the water tank can control external conditions reflecting changes or change the dive depth. This kind of water tank can be placed near the center of the submarine, or it can be placed on the boat separately to prevent the impact on the balance of the boat.
When the submarine descends, the submarine's shell can usually withstand a water pressure of 4 megapascals (equivalent to a pressure of 400 meters), while a submarine with a titanium alloy shell like an alpha-class nuclear submarine can withstand 10 megapascal Pressure (equivalent to a pressure of 1,000 meters water depth). But in the shell, the air pressure around ordinary sea level atmospheric pressure should be maintained. Because the salinity of water is different, the greater the salinity of the water, the more pressure it produces at the same depth. A submarine in a submarine is often in an unstable equilibrium state, or on a submerged or floating surface that dives to the sea floor. Controlling a submarine at a certain depth requires continuous control of the submarine's depth control water tank and the entire water tank system.

The submarine is not inherently balanced while maintaining a fixed buoyancy state. In order to maintain the ideal balance, the submarine is usually controlled by a dedicated balance rudder and an internal balance water tank. The internal water pipes of the balanced water tank communicate with each other, and the water in each balanced water tank is adjusted by a water pump, thereby adjusting the gravity of each part to create a balance upward and downward moment.

Modern submarines rely on electric power to drive the propeller forward. According to the way electricity is generated, it is divided into diesel electric power, nuclear power and AIP. ^[1]

Early history

The submarine can be traced back to Leonardo Da Vinci in the 15th-16th centuries. He is said to have conceived a "boat capable of sailing underwater", but this ability has always been considered "evil", so he did not draw a design. Until the eve of World War I, the submarine was still regarded as a "non-gentlemanlike" weapon, and its captive crew members may be treated as pirates.

In the 16th century, real submarines appeared. In 1578, the British mathematician William Bourne (mathematician) wrote a book "Invention and Design" describing submarines. In 1620, the first written submerible vehicle was built by Cornelius Drebbel, a Dutch-British, mainly based on the former. Design, the propulsive force is generated by human-operated puppets. But some people think that it is just a "bell-shaped thing tied under the surface vessel", and it is not a submarine at all. It has two modified versions that were tested on the Thames in 1620 and 1624. In 2002, the BBC TV program "Building the Impossible" [3], Mark Edwards (boatbuilder) built a two-person ship based on the design drawings of the year. Deborah submarine and successfully snorkeled on Lake Dorney in Eaton.

The "submersible ship" was able to explore the underwater world, but its military value was soon discovered. In 1648, John Wilkins, bishop of Chester, wrote the book Mathematical Magic , which pointed out the advantages of submarines in military strategy:

1.Privacy: Travel to any coast of the world without being discovered or controlled.

2. Security: Pirates and robbers cannot rob underwater vessels; erratic tides and strong wind and rain cannot affect 25-30 feet (5-6 paces) below the sea surface; ice and frost cannot endanger submarine crews, even in the Arctic and Antarctic waters.

3. Effectively resist enemy navy, destroy and sink ships on the surface.

4. Support the place surrounded by or near the water, and deliver supplies silently and silently.

5. It is itself a useful underwater test site.

1800 Nautilus

The first submarine ever used in the military appeared in the American Revolutionary War. Turtle (submarine) was built by David Bushnell of Yale University in the United States, and only one person can operate the rudder and propeller inside. In 1776, the Turtle attempted to attack HMS Eagle, but failed. The first submarine in history to successfully sink enemy ships during the American Civil War. Horace Lawson Hunley built the Hanley submarine, with a crew of eight and driven by a crank. Its front end extends an explosive pack and explodes when it touches an enemy ship. At about 9 pm on February 17, 1864, it successfully sank the USS Housatonic frigate of the Northern Commonwealth, but it also sank due to the vortex generated by the explosion.

Prior to 1863, France first replaced manpower by storing compressed air, and built the first non-human-powered submarine "diver". In 1879, the British Rev. George Garrett built the "Resurrection", about 15 meters long, cylindrical in the middle, and conical at both ends. Its navigation surface is steam-driven and the remaining steam in the submersible boiler is the first heat engine-driven submarine.
In the 1880s, submarines progressed, and countries gradually recognized their importance. The United States, Britain, France, Sweden, Italy, Germany and Russia are all keen on R & D. In 1878, British-American John Philips Holland took up the job. In April 1900, the US government purchased its developed submarine Holland IX and incorporated it into the US Navy. Since then, the submarine has officially become a naval vessel. In 1898, the Frenchman Maxim Lauf was the first to build the "horned whale" with a double shell structure. The ballast water was stored between two hulls. The advantage was that the buoyancy was greatly increased. This later became a type of Soviet Russian submarine.

World War I

German U-9 submarine during World War I

During World War I, the scope of the submarine's activities ranged from nearshore to ocean. Britain and Germany have different submarine strategies. Britain was mainly used to block enemy ports but was unsuccessful due to technical limitations. Germany is engaged in an unrestricted submarine warfare in an attempt to destroy trade and suppress the British shipping route, and then push for peace. However, the British continued to improve escort measures and the large number of US destroyers joined the escort. German submarines were difficult to succeed in the late war and suffered heavy losses and failed.
In 1850, the construction of submarines began in Germany, chaired by its inventor Wilhelm Bauer (born December 23, 1822, died June 20, 1875). In 1890 Nordenfeldt designed the W1 and W2 submarines. In 1904 the Klub shipyard in Kiel was completed and sold to Russia. In 1905, Germany built its own "Karp", a U-1 class submarine. It is a double-shell structure with a Kerting kerosene engine and only one torpedo tube. The next one is a U-2 class, which is half the size, with two launch tubes. In 1912 and 1913, diesel engines began to be installed in the U-19 class. At the start of World War I, Germany had a total of 48 submarines of 13 classes, of which 29 were in service, and the rest were under construction.

In September 1914, a German submarine ambushed the British supply fleet on its way to the port of Ostend. On September 22, 1914, the famous Captain Otto Weddigen commanded a U-9 in an hour, sinking three Cressey-class armored cruisers with only six torpedoes (displacement in (About 12,000 tons)-HMS Cressy, HMS Aboukir and HMS Hogue. Britain lost 36,000 tons of battleships and 1,459 sailors. After 23 days, he sunk the Edgar-class cruiser HMS Hawke with a displacement of 7,770 tons. During the four years of World War I, German U-boats sunk allied ships of the Treaty to millions of tons.

WWII Germany

U-Submarine and Battle of the Atlantic

The Treaty of Versailles after World War I severely restricted Germany from building surface ships and submarines, so Germany cooperated with foreign manufacturers to develop in secret. In conjunction with its experience in the First World War, the German submarine force developed to the strongest and largest in the world during World War II. In contrast, the German surface warships only accelerated their preparation a few years before World War II. Although their quality is high, their overall strength is far inferior to that of the British Royal Navy. Therefore, after the completion of the Bismarck-class battleship, Germany cancelled the construction of some large surface warships (such as the USS Zeppelin, H-class battleship, etc.) due to resource allocation considerations. In addition, the surface fleet s record has been inferior to that of submarines for a long time. Submarine with short time and less resources. Before the end of World War II, Germany had built more than 1,150 submarines.

During World War II, Germany used submarines to cut off allied ocean supplies. The main target was the British Atlantic supply line. It supplies British food, industrial products, and resources and weapons from the United States, which are vital to British life and death. However, although Germany has innovated the technology and tactics of submarines, with the development of war and the involvement of the United States, it has been unable to meet its needs in the middle and late stages of the war. The German Navy uses new radios, Enigma ciphers, and wolf pack tactics to turn submarines into weapons of unprecedented lethality. The U submarine was first deployed in some sea areas to search for enemy transport teams. When it was found, it did not immediately attack, but instead notified other submarines to gather, and then sieged like a "wolf pack", and basically carried out at night. Usually, the transport team cannot resist, especially the small ones. From 1939 to 1943, the German U-submarine wolf pack tactics were unprecedentedly successful, sinking many enemy transport ships, but failed to achieve strategic success for various reasons. In the spring of 1943, the U.S. submarine's construction energy reached its peak, but compared to the increasing number of allied escort ships, the aviation forces' escorting, and the advancement of reconnaissance and search technology (such as radar and sonar), the German submarine force gradually weakened and eventually withdrew. Atlantic routes.

The Allied forces developed a high-frequency directional instrument and cracked the Enigma code machine. As a result, its transport team could detect the U-submarine earlier and strike it before it assembled. Coupled with the large investment of long-range aircraft and escort aircraft carriers, German submarines with much lower endurance than anti-submarine aircraft have suffered devastating blows since. From March to July 1943, Germany lost more than 130 U-submarines, or 41 in May alone. During the same period, the Allied losses fell from 750,000 tons in March to 188,000 tons in July. The Allies were thus able to initiate subsequent Torch Operations, Operation Eskimo, and Normandy Landing.

During World War II, German submarines lost 807 ships, sinking 2882 merchant and combat ships of the Allied forces, totaling 14.4 million tons. There were 264 heavy hitters.

The development process of Chinese submarines

In August 1950, the Navy held a meeting to determine "based on existing forces, focus on the development of new forces such as naval aviation, submarines and torpedo speedboats (referred to as" air, submarine, fast "), and gradually build a strong navy." The army establishment policy decided to give priority to the construction of submarine troops.

On April 20, 1951, the navy selected 275 cadres and soldiers to form a submarine learning team, and went to study in the Soviet Navy Pacific Fleet's submarine sub-unit in Hushun Tigertail.

In May 1952, the Navy began construction of China's first submarine base in Qingdao.

On June 4, 1953, China and the Soviet government signed the "Navy Order Agreement." The Soviet Union transferred to China a paid W-class conventional power attack submarine construction right, provided complete sets of equipment and design drawings, and was assembled and manufactured by the Chinese shipyard. Experts came to China for guidance.

On June 19, 1954, the Navy's first submarine force, the Naval Independent Submarine Brigade, was formally established.

On March 26, 1956, the first W-class submarine assembled and manufactured in China was launched. In October 1957, it was inspected and listed as Model 03.

In 1957, China built its first two submarines and joined the Chinese Navy.

On June 27, 1958, the Central Military Commission approved the top-secret report of the National Defense Industry Commission on "Development of Missile Atomic Submarines."

In 1966, conventional ballistic missile submarines, golf-class submarines launched.

Approved by the Central Military Commission in 1967, China's first-generation conventionally powered torpedo attack submarine was developed by itself.

In April 1974, it was delivered to the Navy Submarine Force, code-named 035 (Ming class).

In November 1968, China's first nuclear-powered attack submarine began construction.

The first nuclear submarine was launched on December 26, 1970.

On August 1, 1974, it was officially incorporated into the Navy's combat sequence and named "Long March 1", code-named Type 091 (Chinese class).

On August 1, 1974, China's first nuclear submarine, Long March One, was commissioned, and China became the fifth country in the world to own a nuclear submarine.

On August 7, 1974, the "Han" class (Type 091) attack nuclear submarine (SSN) was delivered for use.

In December 1976, the East China Sea Fleet 252 broke through the first island chain for the first time and entered the western Pacific for long-distance training.

In March 1980, the 256 boats of the East China Sea Fleet broke through the second island chain and entered the middle of the Pacific Ocean, marking that the Chinese Navy's submarine forces have the capabilities of COSCO.

In April 1981, China's first strategic missile nuclear submarine was launched.

In August 1983, it officially joined the Navy combat sequence, code-named 091 (Xia class).

In October 1982, China successfully launched its first underwater launch of a water arrow, and China became the fifth country in the world to possess a submarine-launched strategic ballistic missile.

In 1983, China's first ballistic missile nuclear submarine was completed and commissioned.

On September 15, 1988, China's self-developed 091 (Xia class) strategic missile nuclear submarine launched the "Julang-1" strategic missile underwater test successfully, and China has now possessed a nuclear counterattack force at sea.

In 1990, the Chinese Navy was equipped with the first type of attack nuclear submarine, code-named 091, and the West called it a Han-class attack nuclear submarine.

In 1993, four advanced Kilo-class conventional submarines were ordered from Russia.

In May 1994, a new conventionally powered attack submarine was launched from the Wuchang Shipyard. Code 039, known in the West as Song-class submarine.

After modification in 1995, it can launch "Julang-2" ballistic missile with a maximum range of 8000 kilometers.

In July 2004, the Yuan-class submarine was successfully developed.

June 24, 2007 marks the 50th anniversary of the establishment of the Chinese Submarine Force.

There are several classifications of military submarines. According to the size of the submarine, it can be classified as large (displacement above 2000 tons), medium (displacement between 600-2000 tons), small (displacement between 100-600 tons) and compact (displacement below 100 tons) submarines. According to mission classification, it can be divided into attack submarines, cruise missile submarines and ballistic missile submarines. According to the hull structure classification, there are double-hull submarines and single-hull submarines (see the structural section for details). According to the submarine power classification, it can be divided into diesel-electric submarines and nuclear submarines.

Submarine attack submarine

Sea Wolf Attacks Nuclear Submarine Since the Turtle attempted to attack enemy ships, the submarine has been regarded as a weapon for undersea attack. The so-called attack submarine is actually different from the strategic submarine. The main task of this submarine is to attack enemy ships, submarines and other targets at sea and under the sea. Land-to-air capabilities are rarely available, or only few orders of magnitude. The main armaments of these submarines gradually developed from the early "ship drills" and "explosive explosives". Until the First World War, torpedoes, mines, and deck guns became standard equipment for submarines. With the rapid development of the German U-submarine underwater after World War II, the deck guns have withdrawn from the historical stage since the U-XXI type.

With the end of World War II and the fall of the "Iron Curtain" of the Cold War, attacking submarines became the reconnaissance intelligence of the United States and the Soviet Union at that time due to their relative cheapness, strong stability, and their own aggressiveness. They sought to track enemy strategic submarines (ballistic missile submarines). ) Important weapon. Especially after the nuclear-powered board of the submarine, the attack submarine can be said to have entered a new era. The exercises involved when the Nautilus was launched into service made all anti-submarine experts at the time surprised its performance. Most of the anti-submarine methods during the World War II were unable to counter the Nautilus. 41]. The United States has since announced that it will no longer build any conventionally powered submarines. Compared with the United States, the quietness of the Soviet submarine has always been somewhat different from that of the United States. However, the world generally believes that the US-built Seawolf-class nuclear submarine and the Soviet-built Akula-Cheetah-class nuclear submarine both represent the highest level of the current single-shell attack submarine and double-shell attack submarine.

Deep sea submarine cruise missile submarine

With the development of submarines, another weapon, the missile, has become another direction of submarine development. The V-II missile became the weapon of the German ideal submarine. The Germans began to study the installation of missiles on the submarine in the late World War II, and the materials of this research project became American trophies with the development of the war. In February 1964, the United States installed the "Tiens" cruise missile on the SS-348 Cod, conducted launch tests and achieved success. However, with the rapid development of submarine ballistic missiles in the United States from the late 1960s to the 1970s, the development of submarine cruise missiles was abandoned.
Compared to the US's abandonment, the Soviet Union made great efforts in the development of cruise missile submarines. This is mainly due to the rapid development of the US aircraft carrier battle group after World War II. At that time, the Soviet Union did not have enough ability to fight against the Allies to develop aircraft carrier formations. In the Soviet anti-aircraft carrier group battle mode, bombers carrying anti-ship missiles and carrying Anti-ship missile submarines were regarded by the Soviet Union as ideal weapons. In 1956, the Soviet Navy converted a W-class submarine to carry an SS-N-3C missile and successfully launched a launch test. Subsequently, the Soviet Union began to develop the first-class cruise missile submarine E-class nuclear submarine. Since then, the Soviet Union has developed a series of Cruise missile submarine. By the time of the Oscar-class nuclear submarine, the Soviet cruise missile submarine had developed to a fairly high altitude.
With the end of the Cold War, the end of large-scale checkoffs and the trend of localized warfare, the United States also recognized the importance of cruise missile submarines. In September 2002, the United States began converting four Ohio-class nuclear submarines into cruise missile launches and special forces launch boats. And the subsequent development of Virginia-class nuclear submarines also installed 12 cruise missile launchers.

Deep sea submarine ballistic missile submarine

Typhoon-class nuclear submarine

Ballistic missile submarines were an important tool in the Cold War's "mutual guarantee of destruction" ideology. The aim is that after we have suffered a destructive nuclear attack from the enemy, and the nuclear-weapon projection forces such as land-based ballistic missiles and air-based strategic bombers have been destroyed, the ballistic missile submarine will give the enemy a devastating blow as a hidden nuclear attack This is called the "second nuclear strike."

Since the test of V-type missiles launched by German test submarines during World War II fell into the hands of the Allies and the Soviets, both sides have been actively engaged in submarine-launched missile experiments after the war. After the United States and the Soviet Union tested the early cruise missiles, both sides began research on submarine-launched ballistic missiles. Especially in the United States, since 1964 to the 1970s, US submarine-launched ballistic missile technology advanced by leaps and bounds. The missiles launched by submarines were mainly converted to ballistic missiles, and cruise missiles were abandoned. More recently, in 1959, the United States' first ballistic missile nuclear submarine, the Washington, entered service. Installed is a Polaris missile with a range of 2200 kilometers. In contrast, the Soviet Union's ballistic missile submarine technology lags behind the United States for a long time. Although the Soviet Union's first ballistic missile submarine (G-class) entered service in 1957, it was earlier than the Washington, but its power was Diesel power, and its P-11M missile range is only 150 kilometers, and only 560 kilometers after modification. After the 1970s, the number and power of ballistic missile submarines on both sides leaped by leaps and bounds, while other countries were dwarfed by comparison with the United States and the Soviet Union. The British ballistic missile submarine is mainly developed based on the Polaris system and the Trident system. The American submarine has a lot in common. France and China have embarked on the path of independent development. The awesome class developed by France entered service in 1971, and then in 1985, the victory class developed by France began to serve. France uses six ballistic missiles as a base, while Britain has four to five. The 092 submarine developed by China was launched in 1981 and used the Julang-1 missile system. In 2007, the Chinese government disclosed the newly developed Type 093 nuclear submarine, and non-official channels also announced some news about the Type 094 nuclear submarine, which used the Julang-2 missile.