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  • In all of World War Two, the world used about 5 megatons of explosives.

  • Now, this is a Trident II missile, capable of carrying 12 nuclear warheads together equivalent

  • in power to about 5 megatons of explosives.

  • A single American Ohio Class submarine can carry 24 Trident II missiles.

  • A single submarine can carry a devastating, catastrophic, inconceivable amount of firepower.

  • While in reality due to arms reduction treaties and practicality these boats often carry far

  • less than their maximum armament, submarines can still creep up anywhere, undetected, ready

  • to unleash their firepower, more powerful that the entire arsenal of some countries,

  • in an instant.

  • Submarines are different in purpose to some other elements of a navy.

  • While an aircraft carrier, for example, is intended to be big, foreboding, and noticeable

  • as a means to display a nation’s power to the world, submarines are meant to to be unseen,

  • undetected, an invisible, silent force that could or could not be anywhere at any time.

  • In a way, submarines almost serve a purpose of psychological warfarean enemy can never

  • know for sure whether a submarine is looming off its shore.

  • While dozens of countries operate submarines, the most powerful and often largest of these

  • boats are those capable of firing ballistic missiles carrying nuclear warheads.

  • Only six nations are confirmed to have these submarinesThe US, UK, France, India, Russia,

  • and China.

  • In addition, analysts have found evidence suggesting that North Korea and Israel also

  • each have nuclear-missile capable submarines.

  • Nowadays, there are essentially two different types of military submarines with two different

  • missions.

  • The attack submarine, the more common kind, is generally smaller and, in combat, attacks

  • other close-range targets like ships using torpedoes, shorter range missiles, and other

  • armaments.

  • The other, often larger type of submarine are those ballistic missile submarines which

  • essentially serve the purpose of being a mobile, hidden launch platform for nuclear missiles.

  • The idea is that, as a stealth launch platform, a country’s submarines would survive any

  • nuclear first strike and therefore be able to retaliate against an aggressor.

  • Ballistic missile submarines are therefore crucial to the idea of mutually assured destructionif

  • anyone attacks with nuclear weapons, assuming those attacked had nuclear weapons that would

  • survive a strike and they retaliated, both the attacker and those attacked would be destroyed.

  • Therefore, many consider these nuclear missile equipped submarines to actually be a form

  • of nuclear deterrencethey say they reduce the likelihood of others using nukes since

  • they assure their subsequent destruction.

  • Considering that these submarines might survive when a country and its government do not,

  • they therefore need the independent authority to use their missiles.

  • While other operators likely have similar setups, it’s known that the UK’s four

  • ballistic missile submarines each have a letter locked in a safe instructing their commander

  • on what to do if the UK is wiped out by a nuclear strike.

  • These letters are written by each prime minister at the beginning of their term and destroyed,

  • unread, at the end.

  • Each PM essentially has to chose which of the four potential options they want to instruct

  • the sub commanders to donothing, to place themselves under the command of an ally like

  • the US or Australia, for the commander to use their judgment, or to retaliate and launch

  • nuclear missiles at the attacker.

  • Of course, what gives submarines their stealth is the blanket of water.

  • American Ohio class submarines are publicly known to be able to go down as deep as 800

  • feet or 250 meters.

  • In reality, it is believed they can go much further.

  • As soon as a sub surfaces, though, their stealth is lost especially in today’s era of satellite

  • tracking.

  • Therefore, it is important that submarines can stay underwater for long periods so that

  • that can dive underwater on one side of the world and make their way to the other undetected.

  • Of course, almost all of the world’s ballistic missile equipped submarines are nuclear powered

  • meaning they have virtually unlimited range.

  • These boat’s reactor cores only need to be swapped every few decades.

  • In addition, most submarines have oxygen generators and desalinators so, like nuclear-powered

  • aircraft carriers, the only thing that really limits how long they can stay deployed is

  • their food supply.

  • How it works on American nuclear subs, which work similarly to those of other countries,

  • is that each boat has two fully staffed crews at any given timethe Blue and Gold crews.

  • The Blue crew will first man the boat while on patrol which lasts, on average, 77 days.

  • The different submarines different patrols are scheduled so that there are always submarines

  • deployed.

  • Despite this long patrol period, in the US Navy at least, submarines are actually known

  • to have the best food of any vessel.

  • Some say it’s because submarines are smallthe chef has nowhere to hide if a meal is bad.

  • It more likely has to do with the fact that submarines get a higher food budget than other

  • vessels.

  • Food is important to morale especially considering submarine duty is one of the Navy’s toughest

  • jobs.

  • Of course, fresh food can only last, at most, two weeks, so the meal quality deteriorates

  • as the weeks go by.

  • Eventually, the only ingredients left are canned, dried, or frozen.

  • The sign of food quality deteriorating does mean that the end of patrol is coming at which

  • time the first crew, the Blue crew, would take the boat back to either its home port

  • or a allied overseas port.

  • The Gold crew will then arrive and then both crews will work to complete a turnover, restocking,

  • and maintenance period of 25 days.

  • Then, the Blue crew will fly home for vacation and subsequent training before the cycle repeats

  • again.

  • Most crew members keep this cycle going for years on end.

  • Submariners even live their days in cycles as well.

  • They work eight hours on then have sixteen off to train, conduct maintenance, work out,

  • eat, and sleep.

  • Now, to get a sense of the scale of the largest of these submarines, here’s a Boeing 747-400

  • and here’s an American Ohio-Class submarine.

  • It is almost 2.5 times longer with a hull circumference far larger than the plane’s

  • fuselage.

  • But even this is not the world’s largest submarine.

  • That title goes to slightly longer and far wider Russian Typhoon-class submarine.

  • These are so large that their amenities include a sauna and small pool.

  • On American and most other submarines, the amenities are more lacking, though.

  • It’s important that submariners have things to do in their down-time considering theyll

  • spend three months without sunlight in a metal tube, but there just isn’t much space.

  • The mess is really the only open space not devoted to work.

  • Submarines tend to have gym equipment but it’s not usually consolidated in one roommore

  • often it’s just spread out in different nooks and crannies.

  • On large Ohio-class submarines, a submariners tiny bunk is their only true personal space.

  • On smaller submarines, like the American Virginia-class, the number of sailors exceeds the number of

  • bunks so the most junior sailors will have to share bunkswhile one works the other

  • sleeps and vice versaand there’s no true personal space.

  • Compared to many surface Navy ships, which have phones, frequent mail deliveries, and

  • even internet, communication to the outside world is limited on submarines.

  • Each submariner is given an email address that their family can send messages to.

  • When the submarine is able to receive communications, all these messages are then sent electronically.

  • Onboard, the messages are all reviewed by a dedicated crew member.

  • They check through to be sure that no information is being sent that they don’t want known

  • by the sailor.

  • For example, they might choose to not pass on information of a family death in order

  • to not affect crew morale.

  • There’s often no way to get sailors off, anyways, so many believe it’s better to

  • leave that news for the end of the patrol.

  • How submarines communicate, though, is complicated because they do, of course, spend months underwater.

  • Almost all radio waves can’t travel through salt water but submarines do need communications

  • to receive orders.

  • Very low frequency radio waves, though, do penetrate water to an extent.

  • That’s why VLF radio forms the core of submarine communication systems.

  • Different navies have large VLF transmittersfor example, the US has ones in Maine, Washington,

  • Hawaii, and elsewhere; India has one on its southern coast; and Australia has one in Western

  • Australia.

  • These VLF signals are able to penetrate the ocean and be picked up by a submarine as deep

  • as 60 feet or 20 meters.

  • One major disadvantage of VLF, though, is that it is very low bandwidth.

  • It can’t even transmit real-time audio signalsthe most it can do is about 700 words per minute

  • in text.

  • When deeper, some submarines also have the capability to launch buoys to shallower depths

  • to receive signals.

  • Submarines also typically can’t respond with VLF frequencies since they don’t have

  • large enough transmitters so they have to raise to shallow depths so they can have antennas

  • sticking out of the water to respond.

  • It’s at this depth that modern submarines will often have quick transmissions with satellites

  • in order to download and upload information.

  • There are a few other techniques used less commonly, some new technologies under development,

  • and some separate systems designed for use when the main systems are compromised, but

  • VLF radio forms the bulk of communications with most submarines.

  • But the fact that submarines spend their time underwater in stealth also makes another crucial

  • element difficultnavigation.

  • Both GPS and Radar don’t work underwater since they use higher frequency waves that

  • can’t make their way through any depth of water.

  • What does work underwater is Sonar where the submarine essentially generates a sound and

  • then listens to when and how the sound comes back to map out its surroundings but emitting

  • this sound makes it quite easy for others to track a submarine.

  • Therefore, when operating in stealth conditions, submarines can’t use active sonar.

  • Rather, they use an inertial navigation system.

  • These are essentially systems of accelerometers and gyroscopes that take the last-known accurate

  • GPS position of a submarine and then tracks the submarines movements relative to that.

  • It uses this to estimate position but of course, as time goes on from the last reliable reading,

  • the accuracy of this system diminishes.

  • 24 hours after the last reading, these will drift to only about 1.15 miles or 1.85 kilometers

  • of accuracy.

  • Now, this technique combined with the consultation of maps is usually fine since most of the

  • time the ocean is a big, wide open space but there are a few objects floating below the

  • surface that submarines could collide withsubmarines.

  • Some modern submarines are so well cloaked that another submarine just feet away might

  • not be able to detect it.

  • That’s what happened on the night of February 3rd, 2009 when the British Navy’s HMS Vanguard

  • submarine felt a resounding bump while sailing in the East Atlantic ocean.

  • It had collided with the French submarine Le Triomphant seemingly just by chance.

  • Luckily they were going at low speed and there were no injuries but, considering both these

  • subs were both equipped with nuclear warheads, one can only imagine the potential consequences

  • of a more damaging collision.

  • Submarines are dangerouseven in peacetime.

  • They are designed to disappear so, after something does go wrong, they often do just disappear.

  • Many submarine operating countries have rescue submarines that can hypothetically be used

  • to save stranded submariners by going down, latching on, and shuttling sailors to the

  • surface but in practice, these have never really had much action.

  • Sometimes submarines sink, their systems fail, and nobody can get to them before oxygen runs

  • out.

  • As submarines become better at masking themselves submarine tracking technology is simultaneously

  • advancing.

  • There’s some thought that there will be a time when nothing can hide in the ocean’s

  • depths but until then, submarines are a crucial aspect of any modern navy.

  • Nowadays, just as they were in World War Two, even traditional, non ballistic-missile submarines

  • and their torpedos are effective and deadly.

  • One of the best ways to track submarines is also by sonar equipped submarines so it’s

  • a situation where countries need submarines because others have submarines.

  • That’s why there are still hundreds of them somewhere, or rather, anywhere, ready to strike

  • at any moment.

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Living Underwater: How Submarines Work

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    joey joey に公開 2021 年 06 月 09 日
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