Modern Submarine Discussions

[Echo_419]

I think Japan is going to be too busy building their own stuff never mind finding time to build Australia anything.

Japanese sure have a lot of capacity building some extra submarines should not be problem for them

 

[Aepsilons]

 

[KalaGhoda]

japs are gonna away at competition at major arms deals in the future.

gonna *eat away..

 

[kurup]

What are your thoughts on Arihant's capabilities?

Arihant-class submarine - Wikipedia, the free encyclopedia

 

[Juggernautjatt]

size of typhoon is quite stupendous

 

[Water Car Engineer]

All the images of "Arihant" people are posting here are actually Akula class SSN India also has.

Akula Class SSN

Arihant Class SSBM

 

[ANMDT]

Australia should discuss building its next-generation fleet of submarines overseas, the Department of Defence said on Monday, a shift that could open the door to a partnership deal with Japan that carries political risk at home and abroad.

Australia is looking for partners to help it build about a dozen diesel-electric submarines to replace its aging Collins Class fleet and help to extend its maritime surveillance deep into the Indian Ocean.

The proposed A$40 billion fleet of submarines is at the core of the nation's maritime defence strategy over the next two decades. Successive governments have pledged to build the vessels in Australia, creating much-needed manufacturing jobs.

The Department of Defence's 50-page Defence Issues Paper 2014, issued on Monday, is part of a public consultation process on a major strategic forces assessment due out next year. In it, the department echoed previous concerns about cost raised by Defence Minister David Johnston.

"There is significant debate emerging about the future submarine and whether it should be built in Australia. This debate must consider the cost, risk and schedule as well as the benefits of the different options," the department said in the paper. "What other military capability might be forgone if monies are committed to industries that do not meet international benchmarks?"

Prime Minister Tony Abbott has struck a tough stance towards struggling industries, declining to bail out anaemic auto manufacturers in a move that deepened acrimony between his government and trade unions.

Any decision to move construction of the submarine fleet overseas would likely cause a further backlash from working class voters.

Japan is considered one of the most likely beneficiaries if Australia does change its stance.
This month, Abbott and Japanese Prime Minister Shinzo Abe signed an agreement on military equipment and technology transfers.
New Australian Navy Submarines to be Japan

Actually Australia had too many experience in ship building and submarine technology , but i dont see why they consider themselves as inefficient to design and build one ?
There are 3 articles in my hands , turned into my head reference during study , and all published by Australian government, one is about possible production of submarine in australia , other 2 are about submarine design and concepts.
Come on guys be a bit competative

 

[Penguin]

One of the goals for the Collins Class program was to advance Australian shipbuilding capabilities, by creating state-owned ASC Pty Ltd. to build a foreign submarine design. The Swedish designed Collins class were the first submarines to be constructed in Australia. Many of those boats have been laid up for very long periods, and there have been a number of periods when the RAN has had just 1 fully operational submarine available – or less. That’s a shaky record .Launching a submarine building industry is admittedly very difficult, and using what amounts to a new design added to that risk.The persistence of serious mechanical issues and very low readiness rates, into 2010 and beyond, raises legitimate questions concerning the long-term risks of Australia’s A$ 36 billion, 12-boat future submarine program.

Australia’s Submarine Program in the Dock

Australia’s submarine fleet among world’s worst

 

[Aepsilons]

Australia’s Submarine Program in the Dock

Australia’s submarine fleet among world’s worst

Good news for both Japan and our Aussie buddies.

 

[Sam Manekshaw]

Submarines are incredible pieces of technology. Not so long ago, a naval force worked entirely above the water; with the addition of the submarine to the standard naval arsenal, the world below the surface became a battleground as well.
The adaptations and inventions that allow sailors to not only fight a battle, but also live for months or even years underwater are some of the most brilliant developments in military history.
In this article, you will see how a submarine dives and surfaces in the water, how life support is maintained, how the submarine gets its power, how a submarine finds its way in the deep ocean and how submarines might be rescued.

Diving and Surfacing:
A submarine or a ship can float because the weight of water that it displaces is equal to the weight of the ship. This displacement of water creates an upward force called the buoyant force and acts opposite to gravity, which would pull the ship down. Unlike a ship, a submarine can control its buoyancy, thus allowing it to sink and surface at will.
To control its buoyancy, the submarine has ballast tanks and auxiliary, or trim tanks, that can be alternately filled with water or air . When the submarine is on the surface, the ballast tanks are filled with air and the submarine's overall density is less than that of the surrounding water. As the submarine dives, the ballast tanks are flooded with water and the air in the ballast tanks is vented from the submarine until its overall density is greater than the surrounding water and the submarine begins to sink (negative buoyancy). A supply of compressed air is maintained aboard the submarine in air flasks for life support and for use with the ballast tanks. In addition, the submarine has movable sets of short "wings" called hydroplanes on the stern (back) that help to control the angle of the dive. The hydroplanes are angled so that water moves over the stern, which forces the stern upward; therefore, the submarine is angled downward.

To keep the submarine level at any set depth, the submarine maintains a balance of air and water in the trim tanks so that its overall density is equal to the surrounding water (neutral buoyancy). When the submarine reaches its cruising depth, the hydroplanes are leveled so that the submarine travels level through the water. Water is also forced between the bow and stern trim tanks to keep the sub level. The submarine can steer in the water by using the tail rudder to turn starboard (right) or port (left) and the hydroplanes to control the fore-aft angle of the submarine. In addition, some submarines are equipped with a retractable secondary propulsion motor that can swivel 360 degrees.
When the submarine surfaces, compressed air flows from the air flasks into the ballast tanks and the water is forced out of the submarine until its overall density is less than the surrounding water (positive buoyancy) and the submarine rises. The hydroplanes are angled so that water moves up over the stern, which forces the stern downward; therefore, the submarine is angled upward. In an emergency, the ballast tanks can be filled quickly with high-pressure air to take the submarine to the surface very rapidly.

Life Support:
There are three main problems of life support in the closed environment of submarine:

• Maintaining the air quality
• Maintaining a fresh water supply
• Maintaining temperature.

Maintaining the Air Quality
The air we breathe is made up of significant quantities of four gases:

• Nitrogen (78 percent)
• Oxygen (21 percent)
• Argon (0.94 percent)
• Carbon dioxide (0.04 percent)

When we breathe in air, our bodies consume its oxygen and convert it to carbon dioxide. Exhaled air contains about 4.5 percent carbon dioxide. Our bodies do not do anything with nitrogen or argon. A submarine is a sealed container that contains people and a limited supply of air. There are three things that must happen in order to keep air in a submarine breathable:

• Oxygen has to be replenished as it is consumed. If the percentage of oxygen in the air falls too low, a person suffocates.
• Carbon dioxide must be removed from the air. As the concentration of carbon dioxide rises, it becomes a toxin.
• The moisture that we exhale in our breath must be removed.

Oxygen is supplied either from pressurized tanks, an oxygen generator (which can form oxygen from theelectrolysis of water) or some sort of "oxygen canister" that releases oxygen by a very hot chemical reaction. Oxygen is either released continuously by a computerized system that senses the percentage of oxygen in the air, or it is released in batches periodically through the day.
Carbon dioxide can be removed from the air chemically using soda lime (sodium hydroxide and calcium hydroxide) in devices called scrubbers. The carbon dioxide is trapped in the soda lime by a chemical reaction and removed from the air. Other similar reactions can accomplish the same goal.
The moisture can be removed by a dehumidifier or by chemicals. This prevents it from condensing on the walls and equipment inside the ship.
In addition, other gases such as carbon monoxide or hydrogen, which are generated by equipment and cigarette smoke, can be removed by burners. Finally, filters are used to remove particulates, dirt and dust from the air.

Maintaining a Fresh Water Supply:
Most submarines have a distillation apparatus that can take in seawater and produce fresh water. The distillation plant heats the seawater to water vapor, which removes the salts, and then cools the water vapor into a collecting tank of fresh water. The distillation plant on some submarines can produce 10,000 to 40,000 gallons (38,000 - 150,000 liters) of fresh water per day. This water is used mainly for cooling electronic equipment (such as computers and navigation equipment) and for supporting the crew (for example, drinking, cooking and personal hygiene).

Maintaining Temperature:
The temperature of the ocean surrounding the submarine is typically 39 degrees Fahrenheit (4 degrees Celsius). The metal of the submarine conducts internal heat to the surrounding water. So, submarines must be electrically heated to maintain a comfortable temperature for the crew. The electrical power for the heaters comes from the nuclear reactor, diesel engine, or batteries (emergency).

Power Supply:
Nuclear submarines use nuclear reactors, steam turbines and reduction gearing to drive the main propeller shaft, which provides the forward and reverse thrust in the water (an electric motor drives the same shaft when docking or in an emergency).
Submarines also need electric power to operate the equipment on board. To supply this power, submarines are equipped with diesel engines that burn fuel and/or nuclear reactors that use nuclear fission. Submarines also have batteries to supply electrical power. Electrical equipment is often run off the batteries and power from the diesel engine or nuclear reactor is used to charge the batteries. In cases of emergency, the batteries may be the only source of electrical power to run the submarine.
A diesel submarine is a very good example of a hybrid vehicle. Most diesel subs have two or more diesel engines. The diesel engines can run propellers or they can run generators that recharge a very large battery bank. Or they can work in combination, one engine driving a propeller and the other driving a generator. The sub must surface (or cruise just below the surface using a snorkel) to run the diesel engines. Once the batteries are fully charged, the sub can head underwater. The batteries power electric motors driving the propellers. Battery operation is the only way a diesel sub can actually submerge. The limits of battery technology severely constrain the amount of time a diesel sub can stay underwater.
Because of these limitations of batteries, it was recognized that nuclear power in a submarine provided a huge benefit. Nuclear generators need no oxygen, so a nuclear sub can stay underwater for weeks at a time. Also, because nuclear fuel lasts much longer than diesel fuel (years), a nuclear submarine does not have to come to the surface or to a port to refuel and can stay at sea longer.
Nuclear subs and aircraft carriers are powered by nuclear reactors that are nearly identical to the reactors used in commercial power plants. The reactor produces heat to generate steam to drive a steam turbine. The turbine in a ship directly drives the propellers, as well as electrical generators. The two major differences between commercial reactors and reactors in nuclear ships are:

• The reactor in a nuclear ship is smaller.
• The reactor in a nuclear ship uses highly enriched fuel to allow it to deliver a large amount of energy from a smaller reactor.

Navigation:

Light does not penetrate very far into the ocean, so submarines must navigate through the water virtually blind. However, submarines are equipped with navigational charts and sophisticated navigational equipment. When on the surface, a sophisticated global positioning system (GPS) accurately determines latitude and longitude, but this system cannot work when the submarine is submerged. Underwater, the submarine usesinertial guidance systems(electric, mechanical) that keep track of the ship's motion from a fixed starting point by usinggyroscopes. The inertial guidance systems are accurate to 150 hours of operation and must be realigned by other surface-dependent navigational systems (GPS, radio,radar, satellite). With these systems onboard, a submarine can be accurately navigated and be within a hundred feet of its intended course.
To locate a target, a submarine uses active and passive SONAR (sound navigation and ranging). Active sonar emits pulses of sound waves that travel through the water, reflect off the target and return to the ship. By knowing the speed of sound in water and the time for the sound wave to travel to the target and back, the computers can quickly calculate distance between the submarine and the target. Whales, dolphins and bats use the same technique for locating prey (echolocation). Passive sonar involves listening to sounds generated by the target. Sonar systems can also be used to realign inertial navigation systems by identifying known ocean floor features .

Rescue:

When a submarine goes down because of a collision with something (such as another vessel, canyon wall or mine) or an onboard explosion, the crew willradio a distress call or launch a buoy that will transmit a distress call and the submarine's location. Depending upon the circumstances of the disaster, the nuclear reactors will shut down and the submarine may be on battery power alone.

If this is the case, then the crew of the submarine have four primary dangers facing them:

• 
  
  
  • Flooding of the submarine must be contained and minimized.
  • Oxygen use must be minimized so that the available oxygen supply can hold out long enough for possible rescue attempts.
  • Carbon dioxide levels will rise and could produce dangerous, toxic effects.
  • If the batteries run out, then the heating systems will fail and the temperature of the submarine will fall.

Rescue attempts from the surface must occur quickly, usually within 48 hours of the accident. Attempts will typically involve trying to get some type of rescue vehicle down to remove the crew, or to attach some type of device to raise the submarine from the sea floor. Rescue vehicles include mini-submarines calledDeep-Submergence Rescue Vehicles (DSRV) and diving bells.
The DSRV can travel independently to the downed submarine, latch onto the submarine over a hatch (escape trunk), create an airtight seal so that the hatch can be opened, and load up to 24 crew members. A diving bell is typically lowered from a support ship down to the submarine, where a similar operation occurs.
To raise the submarine, typically after the crew has been extracted, pontoons may be placed around the submarine and inflated to float it to the surface. Important factors in the success of a rescue operation include the depth of the downed submarine, the terrain of the sea floor, the currents in the vicinity of the downed submarine, the angle of the submarine, and the sea and weather conditions at the surface.

Weapons:
1.Torpedoes:

A torpedo is essentially a guided missile that happens to "fly" underwater . A torpedo therefore has a propulsion system, a guidance system and some sort of explosive device. Torpedoes can travel several miles on their way to the target, and therefore they need a propulsion system that can run for 10 to 20 minutes.
Most missiles that fly through the air use either rocket engines or jet engines, but neither of these work very well underwater. Torpedoes use one of two techniques for propulsion:

• 
  
  
  • Batteries and an electric motor -- This is the same technique that any non-nuclear submarine must use when running underwater.
  • Engines that use special fuel -- Most engines that we are familiar with, like car engines and jet engines, draw their oxygen from the air around the engine and use it to burn a fuel. A torpedo cannot do that, so it uses a fuel that either does not need an oxidizer, or it carries the oxidizer inside the torpedo. OTTO fuel has its own oxidizer mixed with the fuel. Hydrogen Peroxide does not need an oxidizer.

We don't encounter too many fuels that contain their own oxidizers in our normal lives for two reasons. When a fuel has its own oxidizer it tends to make it explosive. Dynamite, for example, has its own oxidizer and it is quite explosive . Rocket engines have to carry their own oxidizer. But because we normally run engines in the air, which has a good supply of oxygen, carrying the oxidizer means extra weight and hassle which is unnecessary.

2.submarine-launched cruise missile (SLCM):

It is a cruise missile that is launched from a submarine (especially a SSG or SSGN). Current versions are typically standoff weapons known as land-attack cruise missiles (LACMs), which are used to attack predetermined land targets with conventional or nuclear payloads. Anti-ship cruise missiles (ASCMs) are also used, and some submarine-launched cruise missiles have variants for both functions. Brahmosis the fastest cruise missile currently developed, and has land-attack and anti-ship variants.
Four US Navy Ohio-class ballistic missile submarines (SSBN) were converted to be able to salvo launch up to 144Tomahawk cruise missiles from their modified vertical launch submarine-launched ballistic missile (SLBM) tubes, as opposed to launching cruise missiles from torpedo tubes as is done from attack submarines. The advantage that the submarines have over guided missile destroyers and cruisers is the ability to remain undetected and launch while submerged. Tomahawk was deployed on US Navy attack submarines beginning in 1983, originally in LACM and ASCM versions, but the ASCM version was withdrawn in the 1990s.
The US Navy's first land-attack cruise missile submarines (4 SSG and 1 SSGN) deployed with the Regulus missile from 1958 until retired in 1964 with the arrival of the Polaris SSBNs in the Pacific.The US deployed the short-range Harpoon anti-ship missile on submarines beginning in 1981. The Soviet Navy converted 13 Whiskey-class submarines (Project 613) for the LACM role in the late 1950s (Whiskey Single Cylinder, Whiskey Twin Cylinder, Whiskey Long Bin), armed with the SS-N-3 Shaddock (P5) missile. As Soviet SSBNs armed with SLBMs became available in the late 1960s, the Shaddock LACM was withdrawn and an ASCM version replaced it. The Echo- and Juliett-class submarines of the 1960s had a similar armament history, with the Echo I's converted to attack submarines because they could not accommodate an anti-ship guidance radar. Then SS-N-3 ASCM was eventually replaced with the SS-N-12 (P-500). Later, the Charlie- and Oscar-classes were designed to use long-range ASCMs, the SS-N-9 (P-120) and SS-N-19 (P-700) respectively. Only the Oscar-class remains in service. The current Akula- and Severodvinsk-class submarines are armed with the SS-N-21 (S-10) LACM.
Jane's Defence Weekly reports that the Dolphin-class submarines are believed to be nuclear armed, offering Israel a sea based second strike capability. In adherence to Missile Technology Control Regime rules the US Clinton administration refused an Israeli request in 2000 to purchase Tomahawk long range SLCMs. The Federation of American Scientists and GlobalSecurity.org report that the four larger torpedo tubes are capable of launching Israeli built nuclear-armed Popeye Turbo cruise missiles


The fore section of a US attack submarine with the doors of the vertical launch system for Tomahawk missiles in the open position
Specific types of SLCMs (LACMs unless noted) include:

• 
  
  
  • Nirbhay (India)
  • BrahMos (India/Russia)
  • BrahMos-II (India/Russia) [Under Development]
  • P-700 Granit (Russia) (ASCM)
  • P-500 Bazalt (Russia) (ASCM)
  • S-10 Granat (Russia)
  • Tomahawk missile (U.S.A)
  • Popeye Turbo SLCM (believed to be an extended-range naval version of the Israeli-made air-launched Popeye) (Israel)
  • Hyunmoo-3 (Cheonryong) (South Korea).

 

[The Archnazi]

thats very gud info, thnx 4 posting

 

[Sam Manekshaw]

thats very gud info, thnx 4 posting

That's basic for the starters

 

[scorpionx]

That's basic for the starters

Very good job, Sam. Please add some more complex info if you have.

 

[Sam Manekshaw]

Very good job, Sam. Please add some more complex info if you have.

For now i am just planning to add more such thread under the banner "Basic"....it will be good to start with for beginners....later i will start adding more complex stuff.

 

[Haitham]

View attachment 47797
Submarines are incredible pieces of technology. Not so long ago, a naval force worked entirely above the water; with the addition of the submarine to the standard naval arsenal, the world below the surface became a battleground as well.
The adaptations and inventions that allow sailors to not only fight a battle, but also live for months or even years underwater are some of the most brilliant developments in military history.
In this article, you will see how a submarine dives and surfaces in the water, how life support is maintained, how the submarine gets its power, how a submarine finds its way in the deep ocean and how submarines might be rescued.

Diving and Surfacing:
A submarine or a ship can float because the weight of water that it displaces is equal to the weight of the ship. This displacement of water creates an upward force called the buoyant force and acts opposite to gravity, which would pull the ship down. Unlike a ship, a submarine can control its buoyancy, thus allowing it to sink and surface at will.
To control its buoyancy, the submarine has ballast tanks and auxiliary, or trim tanks, that can be alternately filled with water or air . When the submarine is on the surface, the ballast tanks are filled with air and the submarine's overall density is less than that of the surrounding water. As the submarine dives, the ballast tanks are flooded with water and the air in the ballast tanks is vented from the submarine until its overall density is greater than the surrounding water and the submarine begins to sink (negative buoyancy). A supply of compressed air is maintained aboard the submarine in air flasks for life support and for use with the ballast tanks. In addition, the submarine has movable sets of short "wings" called hydroplanes on the stern (back) that help to control the angle of the dive. The hydroplanes are angled so that water moves over the stern, which forces the stern upward; therefore, the submarine is angled downward.
View attachment 47799
View attachment 47800

To keep the submarine level at any set depth, the submarine maintains a balance of air and water in the trim tanks so that its overall density is equal to the surrounding water (neutral buoyancy). When the submarine reaches its cruising depth, the hydroplanes are leveled so that the submarine travels level through the water. Water is also forced between the bow and stern trim tanks to keep the sub level. The submarine can steer in the water by using the tail rudder to turn starboard (right) or port (left) and the hydroplanes to control the fore-aft angle of the submarine. In addition, some submarines are equipped with a retractable secondary propulsion motor that can swivel 360 degrees.
When the submarine surfaces, compressed air flows from the air flasks into the ballast tanks and the water is forced out of the submarine until its overall density is less than the surrounding water (positive buoyancy) and the submarine rises. The hydroplanes are angled so that water moves up over the stern, which forces the stern downward; therefore, the submarine is angled upward. In an emergency, the ballast tanks can be filled quickly with high-pressure air to take the submarine to the surface very rapidly.

Life Support:
There are three main problems of life support in the closed environment of submarine:

• Maintaining the air quality
• Maintaining a fresh water supply
• Maintaining temperature.

Maintaining the Air Quality
The air we breathe is made up of significant quantities of four gases:

• Nitrogen (78 percent)
• Oxygen (21 percent)
• Argon (0.94 percent)
• Carbon dioxide (0.04 percent)

When we breathe in air, our bodies consume its oxygen and convert it to carbon dioxide. Exhaled air contains about 4.5 percent carbon dioxide. Our bodies do not do anything with nitrogen or argon. A submarine is a sealed container that contains people and a limited supply of air. There are three things that must happen in order to keep air in a submarine breathable:

• Oxygen has to be replenished as it is consumed. If the percentage of oxygen in the air falls too low, a person suffocates.
• Carbon dioxide must be removed from the air. As the concentration of carbon dioxide rises, it becomes a toxin.
• The moisture that we exhale in our breath must be removed.

Oxygen is supplied either from pressurized tanks, an oxygen generator (which can form oxygen from theelectrolysis of water) or some sort of "oxygen canister" that releases oxygen by a very hot chemical reaction. Oxygen is either released continuously by a computerized system that senses the percentage of oxygen in the air, or it is released in batches periodically through the day.
Carbon dioxide can be removed from the air chemically using soda lime (sodium hydroxide and calcium hydroxide) in devices called scrubbers. The carbon dioxide is trapped in the soda lime by a chemical reaction and removed from the air. Other similar reactions can accomplish the same goal.
The moisture can be removed by a dehumidifier or by chemicals. This prevents it from condensing on the walls and equipment inside the ship.
In addition, other gases such as carbon monoxide or hydrogen, which are generated by equipment and cigarette smoke, can be removed by burners. Finally, filters are used to remove particulates, dirt and dust from the air.

Maintaining a Fresh Water Supply:
Most submarines have a distillation apparatus that can take in seawater and produce fresh water. The distillation plant heats the seawater to water vapor, which removes the salts, and then cools the water vapor into a collecting tank of fresh water. The distillation plant on some submarines can produce 10,000 to 40,000 gallons (38,000 - 150,000 liters) of fresh water per day. This water is used mainly for cooling electronic equipment (such as computers and navigation equipment) and for supporting the crew (for example, drinking, cooking and personal hygiene).

Maintaining Temperature:
The temperature of the ocean surrounding the submarine is typically 39 degrees Fahrenheit (4 degrees Celsius). The metal of the submarine conducts internal heat to the surrounding water. So, submarines must be electrically heated to maintain a comfortable temperature for the crew. The electrical power for the heaters comes from the nuclear reactor, diesel engine, or batteries (emergency).

Power Supply:
Nuclear submarines use nuclear reactors, steam turbines and reduction gearing to drive the main propeller shaft, which provides the forward and reverse thrust in the water (an electric motor drives the same shaft when docking or in an emergency).
Submarines also need electric power to operate the equipment on board. To supply this power, submarines are equipped with diesel engines that burn fuel and/or nuclear reactors that use nuclear fission. Submarines also have batteries to supply electrical power. Electrical equipment is often run off the batteries and power from the diesel engine or nuclear reactor is used to charge the batteries. In cases of emergency, the batteries may be the only source of electrical power to run the submarine.
A diesel submarine is a very good example of a hybrid vehicle. Most diesel subs have two or more diesel engines. The diesel engines can run propellers or they can run generators that recharge a very large battery bank. Or they can work in combination, one engine driving a propeller and the other driving a generator. The sub must surface (or cruise just below the surface using a snorkel) to run the diesel engines. Once the batteries are fully charged, the sub can head underwater. The batteries power electric motors driving the propellers. Battery operation is the only way a diesel sub can actually submerge. The limits of battery technology severely constrain the amount of time a diesel sub can stay underwater.
Because of these limitations of batteries, it was recognized that nuclear power in a submarine provided a huge benefit. Nuclear generators need no oxygen, so a nuclear sub can stay underwater for weeks at a time. Also, because nuclear fuel lasts much longer than diesel fuel (years), a nuclear submarine does not have to come to the surface or to a port to refuel and can stay at sea longer.
Nuclear subs and aircraft carriers are powered by nuclear reactors that are nearly identical to the reactors used in commercial power plants. The reactor produces heat to generate steam to drive a steam turbine. The turbine in a ship directly drives the propellers, as well as electrical generators. The two major differences between commercial reactors and reactors in nuclear ships are:

• The reactor in a nuclear ship is smaller.
• The reactor in a nuclear ship uses highly enriched fuel to allow it to deliver a large amount of energy from a smaller reactor.

Navigation:
View attachment 47801
Light does not penetrate very far into the ocean, so submarines must navigate through the water virtually blind. However, submarines are equipped with navigational charts and sophisticated navigational equipment. When on the surface, a sophisticated global positioning system (GPS) accurately determines latitude and longitude, but this system cannot work when the submarine is submerged. Underwater, the submarine usesinertial guidance systems(electric, mechanical) that keep track of the ship's motion from a fixed starting point by usinggyroscopes. The inertial guidance systems are accurate to 150 hours of operation and must be realigned by other surface-dependent navigational systems (GPS, radio,radar, satellite). With these systems onboard, a submarine can be accurately navigated and be within a hundred feet of its intended course.
To locate a target, a submarine uses active and passive SONAR (sound navigation and ranging). Active sonar emits pulses of sound waves that travel through the water, reflect off the target and return to the ship. By knowing the speed of sound in water and the time for the sound wave to travel to the target and back, the computers can quickly calculate distance between the submarine and the target. Whales, dolphins and bats use the same technique for locating prey (echolocation). Passive sonar involves listening to sounds generated by the target. Sonar systems can also be used to realign inertial navigation systems by identifying known ocean floor features .

Rescue:
View attachment 47802
When a submarine goes down because of a collision with something (such as another vessel, canyon wall or mine) or an onboard explosion, the crew willradio a distress call or launch a buoy that will transmit a distress call and the submarine's location. Depending upon the circumstances of the disaster, the nuclear reactors will shut down and the submarine may be on battery power alone.

If this is the case, then the crew of the submarine have four primary dangers facing them:

• 
  
  
  • Flooding of the submarine must be contained and minimized.
  • Oxygen use must be minimized so that the available oxygen supply can hold out long enough for possible rescue attempts.
  • Carbon dioxide levels will rise and could produce dangerous, toxic effects.
  • If the batteries run out, then the heating systems will fail and the temperature of the submarine will fall.

Rescue attempts from the surface must occur quickly, usually within 48 hours of the accident. Attempts will typically involve trying to get some type of rescue vehicle down to remove the crew, or to attach some type of device to raise the submarine from the sea floor. Rescue vehicles include mini-submarines calledDeep-Submergence Rescue Vehicles (DSRV) and diving bells.
The DSRV can travel independently to the downed submarine, latch onto the submarine over a hatch (escape trunk), create an airtight seal so that the hatch can be opened, and load up to 24 crew members. A diving bell is typically lowered from a support ship down to the submarine, where a similar operation occurs.
To raise the submarine, typically after the crew has been extracted, pontoons may be placed around the submarine and inflated to float it to the surface. Important factors in the success of a rescue operation include the depth of the downed submarine, the terrain of the sea floor, the currents in the vicinity of the downed submarine, the angle of the submarine, and the sea and weather conditions at the surface.

Weapons:
1.Torpedoes:
View attachment 47803

A torpedo is essentially a guided missile that happens to "fly" underwater . A torpedo therefore has a propulsion system, a guidance system and some sort of explosive device. Torpedoes can travel several miles on their way to the target, and therefore they need a propulsion system that can run for 10 to 20 minutes.
Most missiles that fly through the air use either rocket engines or jet engines, but neither of these work very well underwater. Torpedoes use one of two techniques for propulsion:

• 
  
  
  • Batteries and an electric motor -- This is the same technique that any non-nuclear submarine must use when running underwater.
  • Engines that use special fuel -- Most engines that we are familiar with, like car engines and jet engines, draw their oxygen from the air around the engine and use it to burn a fuel. A torpedo cannot do that, so it uses a fuel that either does not need an oxidizer, or it carries the oxidizer inside the torpedo. OTTO fuel has its own oxidizer mixed with the fuel. Hydrogen Peroxide does not need an oxidizer.

We don't encounter too many fuels that contain their own oxidizers in our normal lives for two reasons. When a fuel has its own oxidizer it tends to make it explosive. Dynamite, for example, has its own oxidizer and it is quite explosive . Rocket engines have to carry their own oxidizer. But because we normally run engines in the air, which has a good supply of oxygen, carrying the oxidizer means extra weight and hassle which is unnecessary.
2.submarine-launched cruise missile (SLCM):
View attachment 47804
It is a cruise missile that is launched from a submarine (especially a SSG or SSGN). Current versions are typically standoff weapons known as land-attack cruise missiles (LACMs), which are used to attack predetermined land targets with conventional or nuclear payloads. Anti-ship cruise missiles (ASCMs) are also used, and some submarine-launched cruise missiles have variants for both functions. Brahmosis the fastest cruise missile currently developed, and has land-attack and anti-ship variants.
Four US Navy Ohio-class ballistic missile submarines (SSBN) were converted to be able to salvo launch up to 144Tomahawk cruise missiles from their modified vertical launch submarine-launched ballistic missile (SLBM) tubes, as opposed to launching cruise missiles from torpedo tubes as is done from attack submarines. The advantage that the submarines have over guided missile destroyers and cruisers is the ability to remain undetected and launch while submerged. Tomahawk was deployed on US Navy attack submarines beginning in 1983, originally in LACM and ASCM versions, but the ASCM version was withdrawn in the 1990s.
The US Navy's first land-attack cruise missile submarines (4 SSG and 1 SSGN) deployed with the Regulus missile from 1958 until retired in 1964 with the arrival of the Polaris SSBNs in the Pacific.The US deployed the short-range Harpoon anti-ship missile on submarines beginning in 1981. The Soviet Navy converted 13 Whiskey-class submarines (Project 613) for the LACM role in the late 1950s (Whiskey Single Cylinder, Whiskey Twin Cylinder, Whiskey Long Bin), armed with the SS-N-3 Shaddock (P5) missile. As Soviet SSBNs armed with SLBMs became available in the late 1960s, the Shaddock LACM was withdrawn and an ASCM version replaced it. The Echo- and Juliett-class submarines of the 1960s had a similar armament history, with the Echo I's converted to attack submarines because they could not accommodate an anti-ship guidance radar. Then SS-N-3 ASCM was eventually replaced with the SS-N-12 (P-500). Later, the Charlie- and Oscar-classes were designed to use long-range ASCMs, the SS-N-9 (P-120) and SS-N-19 (P-700) respectively. Only the Oscar-class remains in service. The current Akula- and Severodvinsk-class submarines are armed with the SS-N-21 (S-10) LACM.
Jane's Defence Weekly reports that the Dolphin-class submarines are believed to be nuclear armed, offering Israel a sea based second strike capability. In adherence to Missile Technology Control Regime rules the US Clinton administration refused an Israeli request in 2000 to purchase Tomahawk long range SLCMs. The Federation of American Scientists and GlobalSecurity.org report that the four larger torpedo tubes are capable of launching Israeli built nuclear-armed Popeye Turbo cruise missiles


The fore section of a US attack submarine with the doors of the vertical launch system for Tomahawk missiles in the open position
Specific types of SLCMs (LACMs unless noted) include:

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  • Nirbhay (India)
  • BrahMos (India/Russia)
  • BrahMos-II (India/Russia) [Under Development]
  • P-700 Granit (Russia) (ASCM)
  • P-500 Bazalt (Russia) (ASCM)
  • S-10 Granat (Russia)
  • Tomahawk missile (U.S.A)
  • Popeye Turbo SLCM (believed to be an extended-range naval version of the Israeli-made air-launched Popeye) (Israel)
  • Hyunmoo-3 (Cheonryong) (South Korea).

Thanks for great info
but i have 2 questions??
1- How cruise missiles reach sea surface???
2- Types of guidance of torpedoes???