Submarine warfare is far darker and more disturbing than anyone who hasn’t experienced [music] it could ever really understand.

They are incredibly powerful weapons, but what you’re about to see is how bad it really is to be a member of a submarine crew and what happens when anti-ubmarine weapons hit them.

So, let’s go all the way back to how submarines were introduced into warfare.

And it might shock you how far back this goes in history.

The first ever recorded thing we could call a submarine was Cornelis Drebel’s craft made for King James I of England in the 1620s.

It was basically a small rowboat sealed in greased leather.

It even had [music] ballast technology with pigkin bladders that the crew would squeeze to push out the water when they wanted to surface while snorkelike tubes provided air inside.

It could go about 15 ft below the surface for several hours.

Barely functional but proof that underwater travel was possible.

Then during the American Revolution in the 1770s, a submarine attacked an enemy ship for the first time in history.

Inventor David Bushnell built the Turtle, a one-man wooden submersible powered by a handc cranked screw and foot pedals armed with a 150lb gunpowder charge that was intended to be screwed onto an enemy ship’s hull.

The Turtle was used in combat, but the attack failed when the charge couldn’t [music] be attached to the ship.

Still, the first important lessons were learned, and it showed what underwater attacks could do.

Soon after came the [music] first successful submarine attack and simultaneously the first of many submarine tragedies.

On February 17th, 1864 during the American Civil War, the Confederate submarine HL Hunley attacked the Union ship Houseonic.

This submarine was a 40ft craft made of iron and powered by a handc cranked propeller with eight crewmen.

In front of it was a 135 lb spar torpedo attached to a long pole.

The crew managed to reach the Union ship underwater and activate the charge.

The explosion [music] sent Houseonic to the bottom, but Hunley never resurfaced after the mission.

No one knew what happened for years [music] until the wreck was found in 2000 with all crew members skeletons still at their stations.

What exactly happened to them was never determined, but you’d agree that with such technology, there were more than enough things that could go wrong and kill you underwater.

They didn’t have electricity or ventilation, and light came from candles, which also served as their carbon dioxide gauge.

If the candles went out, it meant low oxygen inside.

Not to mention leaks, disorientation, and implosion if they went too deep, while navigation relied on compass and guesswork with luck as a major factor.

Even during testing, Hunley sank twice, drowning two crews and her designer before the final mission.

Then came the late 19th century, and submarine technology was about to go through its biggest development, soon to be tested in battle on a previously unimaginable scale.

The biggest problem at first was finding the right way to propel the vessel while submerged.

Designers experimented with steam, petrol, and electric power, which at the time seemed to promise a solution.

On the surface, diesel or petrol engines powered the vessel and recharged lead acid batteries.

Those batteries then powered electric motors when submerged.

Electric motors were quiet with no exhaust, and they gave submarines about 4 to 8 hours of submersion, depending on speed.

We call them submarines, but they were more like small, narrow torpedo [music] boats that could go underwater for a brief time, far from the standards of today’s submarines.

However, this was revolutionary for the time and soon based on this design, the first submarines went into service with several countries [music] navies.

The Germans were at first skeptical of their early hubot, which by the way is short for un seab boot.

Their main weapon was, of course, the torpedo.

At first, it used compressed air to drive a small propeller and carry a warhead of about 100 to 200 lb of explosive.

Early torpedoes were anything but accurate or reliable, and launching one was almost as dangerous for the submarine crew as for the ship they were attacking.

They could detonate prematurely or even circle back toward the submarine that launched them.

And of course, a large percentage were duds even when [music] they managed to hit the enemy ship.

There was no air purification system and they were diving literally as if you sat in your car and went underwater breathing the same air inside until your head started hurting or you became dizzy hoping that no one would spot you during the night so you could surface to charge batteries and ventilate the yubot where around 80 people were sweating, eating, sleeping, and using the same small toilet.

I really hope you’re not eating while watching this video.

Before even going into the dangers of combat, there was the danger of simply being on these early submarines.

fire batteries releasing toxic gas and water leaks.

If anything went wrong with the ballast system, it could send you nose diving straight to the bottom of the ocean where pressure would crush the sub like a tin can.

Perhaps an even worse scenario, which sadly happened to disturbingly many submarines, even the most modern ones, was to hit bottom in shallower waters where pressure wouldn’t kill you, but you’d be without power on the seabed, several hundred meters deep with water probably leaking in and no rescue possible.

You’d just wait for hypoxia, hypothermia, or the water itself to finish the job.

So, how exactly did submarine warfare begin in World War I? And why was it so bad? Well, before spiraling into one of the most feared and controversial forms of combat, it began in a surprisingly experimental [music] way.

These early submarines were seen as defensive weapons meant to ambush enemy ships.

But then the Germans got the idea to turn them into a terror weapon, a kind of underwater siege tool.

When World War I broke out in 1914, the German Imperial Navy had about 20 operational yubot.

They knew there was no chance to defeat the British Royal Navy, the strongest in the world in open and fair conventional naval combat.

So, they turned to yubot to gain an advantage.

Just weeks into the war, German U9 attacked three British cruisers patrolling the North Sea in close formation and sank all three within an hour.

Over 1,400 British sailors died.

But this was only the beginning because the Germans realized that by attacking merchant shipping, they could undermine Britain’s ability to wage war and basically besiege the [music] island right under the nose of its powerful surface fleet.

Germany declared unrestricted submarine warfare and sent every available yubot to attack any ship around Britain, military or not.

At first, both sides tried to follow long-standing maritime laws known as prize rules.

A warship or in this case a yubot could stop an enemy merchant vessel board and search it and if it was found to be carrying supplies for the enemy the crew would be ordered to abandon the ship before sinking it.

It was considered a matter of honor and at first tried to follow those rules.

However, that chivalry didn’t last long because the British began arming their merchant ships with deck guns and creating so-called Q ships.

Disguised merchant ships built specifically to hunt submarines.

When a hubot surfaced to stop them for inspection, they’d open fire on it.

So, the honorable rules of war went out the window quickly.

In only 6 months of 1915, more than 500 ships were sunk around England by hubot.

The most famous example was RMS Lucatania, which had 2,000 people aboard and also turned out to be carrying ammunition for Britain.

It was hit by U20, and the torpedo triggered a massive internal explosion, sending the huge ocean liner to the bottom in just 18 minutes.

Around 1,200 people died, including 128 Americans, which is said to be one of the reasons America entered the war.

Merchant ships sailing unprotected now had to form convoys with destroyers and aircraft patrolling around them for protection, shutting their lights off at night [music] and sailing in zigzag patterns to make them harder targets for yubot.

But the Germans introduced newer and [music] bigger yubot, and the cat-and- mouse game continued.

It reached the point where Britain’s food supplies dropped to just a few weeks worth because so few ships were reaching [music] the island.

By 1917, America had entered the war and threw everything it had against the German Yubot.

Naval crews began using hydrophones to listen for the hum of yubot propellers and engines, roughly locating them by sound and dropping a pattern of depth charges set to explode at different depths to increase the chances of hitting them.

An underwater explosion sent a shock wave that if close enough could rupture a yubot’s hull or force it to the surface.

After the explosion, sailors looked for oil washing up on the surface, which indicated that the yubot had been destroyed along with its 80man crew.

There were also other attempts to counter Yubot, like underwater mines and nets.

Mines were used, much like on land, to deny certain areas and turn them into kill zones.

These were large and powerful.

A single one could easily destroy a Ubot or even a larger vessel.

Nets were made of heavy steel mesh and wire stretched across important narrow passages to deny [music] access to Ubot or protect harbors.

If a yubot hit a net, it could get entangled and be forced to surface where it would then be destroyed.

The Allies operated early submarines in the First World War as well, but they were mostly used for blockading [music] and patrolling, sinking about 200 ships throughout the war.

They were nowhere near as heavily used as the German Ubot, so they didn’t suffer such horrific losses.

When the war ended, [music] 178 German Hubot had been destroyed, more than half of their total, and 5,000 out of 17,000 crew members were killed.

[music] However, that was still nothing compared to what was about to happen in the next world war.

After losing the war, the Germans had to surrender all their surviving Yubot and were banned under the Treaty of Versailles from producing them again.

But the Germans, knowing how effective yubot were, got creative and found ways to develop them anyway.

[music] In the 1930s, Adolf Hitler and Admiral Carl Dernit began rebuilding the Yubot fleet through covert dummy firms in other countries.

They soon came up with the Type 7, a robust 220 ft boat that carried 11 torpedoes and an improved diesel electric system, giving it a range of about 7,000 mi.

Soon after came the even larger Type 9.

They could travel as far as South America and Africa and carry twice as many torpedoes.

By 1939, Germany had 56 operational yubot ready to terrorize allied vessels [music] once again in what German crews called the first happy time.

When war broke out, Hubot, [music] learning from the previous war, immediately attacked commerce.

And before Allied protective systems could be deployed, they sank over 270 Allied merchant ships, sending about 1.

5 million tons of supplies to the bottom.

They used new Wolfpack tactics to make their small fleet far more effective.

Boats would patrol independently, and when one cited an Allied convoy, it would radio others to converge for a coordinated night attack.

They followed the convoys and under the cover of night surfaced and attacked from all directions, diving again before defenders could organize to fight back.

It was a devastating tactic, even against wellprotected convoys.

The first happy time lasted until the British improved their escorts and air patrols searched diligently for any sign of yubot.

But then came the second happy [music] time when Germany declared war on the United States.

Yubot now attacked America’s completely unprotected eastern coast in Operation Drum Beatat.

Five type 9 boats crossed the Atlantic and began wreaking havoc on American ships.

They sank 25 vessels in just 3 weeks.

And when reinforcement hubot arrived within months, they had sunk 609 allied ships.

This slaughter forced an urgent response from the allies because there was no way to sustain such horrible losses.

That response over the next few years would not only end the second and last German happy time, but also seal the fate of Yubot crews.

By the final months of World War II, they would reach a death rate of 90%.

[music] And you’re now going to see why.

The first major step was strict convoy discipline and purpose-built escorts.

These were smaller ships that acted as bodyguards for merchant vessels.

They were equipped with early versions of sonar and depth charges and were constantly on the lookout for any signs of hubot.

The allies built a system to turn this against them because German yubot coordinated by radio with short messages to organize wolf packs.

The so-called Huffduff system caught these signals and measured which direction they came from.

A single ship with this device couldn’t pinpoint the exact [music] location, only the direction.

But several ships working together and sharing their data could pretty much tell exactly where the signal was coming from.

With this knowledge, vulnerable merchant ships would change course to avoid ambushes, while anti-ubmarine ships raced in to drop depth charges there.

But something then happened that completely turned the Battle of the Atlantic in favor of the Allies.

You’ve probably heard about the German Enigma machine, a mechanical device that encrypted their radio messages and could only be decrypted by another Enigma.

This way, communication remained secret.

[music] And even if the Allies intercepted a message, they couldn’t understand it.

However, in May 1941, the Royal Navy captured German U110.

And before it sank and the crew could destroy it, they managed to seize an intact Enigma machine and code books.

This provided the missing link for Allied intelligence, which had been working to break the code since the beginning of the war.

Soon, the Allies could read German messages, but they had to make sure the Germans never realized it.

So, they carefully chose which intercepted messages to act on, and even some surprise attacks that they knew were coming had to be allowed to happen without warning friendly units, so the Germans wouldn’t suspect their code had been broken.

Anti-ubmarine technology improved drastically from the beginning of the war with new sonars and radars.

These were now mounted on specialized aircraft for hunting yubot and providing air cover to convoys.

Attacking convoys under air cover was completely suicidal for yubot.

Ships carried various anti-ubmarine weapons like the hedgehog mortar which fired 24 depth charges that exploded on impact.

There were acoustic homing torpedoes that locked onto the propeller noise of yubot and were dropped by aircraft.

Later in the war, aircraft carried rockets and cannons for submarine hunting, such as the Mosquito Bomber with its 57mm gun that could punch through a submarine’s hull with ease.

With all these factors combined, life for the German Yubot crews became incredibly dangerous and well, short.

In May 1943 alone, 41 Yubot were destroyed.

Out of about 1,160 Germanot, 785 were destroyed throughout the war.

And listen to this.

Out of 40,000 crewmen, roughly 30,000 were killed.

So yes, they caused a lot of damage to the Allied war effort, but being a Yubot crewman was almost a death sentence and a death sentence in perhaps some of the worst possible ways.

After World War II, submarines only continued to evolve with the biggest change being the introduction of nuclear power in 1955.

USS Nautilus became the first nuclearpowered submarine and completely changed underwater warfare.

Powered by a nuclear reactor and packed with other cuttingedge technologies, modern submarines are limited only by how long the crew can go without resupply, practically just by food.

In theory, they can stay submerged indefinitely.

In simple terms, a nuclear reactor creates heat that boils water to produce steam, which [music] then turns turbines that propel the submarine and drive generators that make electricity.

When the steam cools, it condenses back into water, and the cycle begins again with no need to surface for anything.

at least as long as nothing breaks down.

[music] A nuclear reactor can last about 20 years before needing service.

Modern submarines also have air purification systems and a way to make oxygen through a process called electrolysis.

Seawater is pumped into a machine that [music] through a chemical reaction splits the molecules into hydrogen and oxygen.

They can also desalinate seawater and turn it into drinking [music] water.

This means modern submarines can remain submerged for months and the only real limitations are food and the sanity of the crew.

It’s not great for mental health to spend 6 months underwater in a cramped interior with a hundred other men.

And that’s not even counting the lack of sunlight and other health issues that come with being a submariner.

With nuclear reactors and modern nuclear warheads, torpedoes, and ballistic missiles, the dangers and responsibilities [music] are still there.

And there have been several horrific accidents, even with the most modern submarines.

But we could talk about those in another video if you’re interested.