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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 than 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, for boarding and noticeable
就是要大 引人注目 用来起降飞机
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 given time.
in a way, submarines almost serve a purpose of psychological warfare
an 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 submarines—
The US, UK, France, India, Russia, and China.
分别是美国 英国 法国 印度 俄罗斯和中国
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 destruction
if anyone attack 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 deterrence
they 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 do nothing
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 time
—the 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 small,
the 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.
进行维护工作 锻炼 吃饭和睡觉
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 they’ll 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 room
more 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 bunks
while one works the other sleeps and vice versa
and 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.
On board, 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 transmitters
for example, the US has ones in Maine, Washington, Hawaii, and elsewhere;
如美国在缅因 华盛顿 夏威夷等地都有一台
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 signals
the 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 difficult—navigation.
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,
但显然 随着时间变化 从最后一个准确读数开始
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 with—submarines.
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 dangerous—even 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
通过下潜 锁定 把艇员送回水面的方式
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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