For thousands of years, humans have traveled on the water and have wondered if it was possible to travel under the water like a fish.
The idea of underwater travel stuck around for centuries, but eventually, humans did figure out how to travel underwater, even if the first efforts were not successful.
Learn more about the submarine, how it was invented, and how they work, on this episode of Everything Everywhere Daily.
The idea of traveling underwater goes back a long way. All it took was to look at a fish swimming to wonder what it would be like to be the fish.
When humans started using ships to engage in warfare, it didn’t require much imagination to realize that if you could sneak up on your enemy below the surface of the water, you could wreak havoc on them.
There are images of ancient Egyptians who used papyrus reeds to breathe underwater to sneak up on prey while hunting.
Likewise, Alexander the Great supposedly used an early diving bell during the siege of Tyre in what is modern-day Lebanon.
These of course weren’t really submersible vehicles, but they did show the desire to be able to travel and explore underwater.
The problem of underwater transportation was actually much bigger than the ancients realized.
First, you need a body for your vehicle that will be water-tight. Ancient ships were made out of wood, which would often have slow leaks. The state of metallurgy at the time wouldn’t have allowed for water-tight seams between metal sheets to make up the hull.
This is especially true when you consider the great pressures that submarines face when they are underwater. For every 10 meters you descend below the surface, water pressure increases by one atmosphere. Holding back pressurized water is much more challenging than trying to be water-tight at the surface.
Then you need to be able to control your buoyancy. It is easy to build a ship that floats. It would also be easy to build a ship that would sink to the bottom of the sea. What is really challenging is to create a vessel that can ascend, descend, and hover at depth.
Next, you need a system of propulsion. Ships usually had two methods of propulsion: sails and oars. Sails obviously can’t work underwater, and oars require you to take the oar out of the water, move it through less dense air, and then back into denser water.
Finally, and most obviously, you have to be able to breathe. This is what made undersea transportation so dangerous. An enclosed space only has so much oxygen. If the vessel leaks, it will fill up with water, and you have no oxygen.
All of these problems would need to be solved if underwater vehicles were to be practical.
The first person we know of who seriously considered the problem of underwater travel was the English mathematician ??William Bourne. He came up with plans for a submarine in a book of inventions he published in 1578. Nothing was ever built, but it was an example of serious thought given to the topic.
The first attempt at actually building something which could be submerged was undertaken by the Dutch engineer ??Cornelis Drebbel. He built an oar-powered submersible for King James I of England in 1620. Technically, since it was powered by oars, it would be categorized as semi-submersible.
There was no practical application found for his device, and it was soon forgotten.
The 18th century saw several patents filed on the concept of a submersible craft. They addressed the problems of ballast, propulsion, and stability.
The first real big breakthrough in submersible watercraft occurred in 1775 with the creation of the Turtle.
The Turtle was a semi-submersible craft built by American inventor David Bushnell. It looked like a large apple-shaped wooden barrel. Just a small turret would sit above the water line which allowed the person inside to see and breathe.
Inside there were two cranks attached to water screws outside the vehicle for propulsion. There was also a bilge system to provide ballast.
The goal of the vehicle was to sneak up on British ships in New York Harbor and attach gunpowder explosives to the hulls to sink them.
It was a very difficult ship to maneuver as it was propelled and steered by a single person inside.
On September 6, 1776, the Turtle actually went out to attack the British flagship Eagle which was in New York Harbor. The Turtle managed to make it to the hull of the ship, however, it had to literally drill a hole to attach the explosives. It failed to drill the hole because of a copper lining outside the ship’s hull.
Even though it wasn’t successful, it was the first actual use of a submersible craft in military history.
In 1800, American Robert Fulton, the inventor of the steamboat, built a ship called the Nautilus in France. It was a long cylinder, which at least superficially looked like the shape of a modern submarine. It had a hand crank for underwater propulsion and a sail for when it was at the surface.
The big innovation was that it had tanks of compressed air which allowed the two-person crew to breathe when they were underwater. It also had a snorkel which allowed for unlimited air when it was near the surface. With the compressed air, the crew could stay submerged for five hours.
In 1801, he took the Nautilus down to a then-record depth of 25 feet or 7.5 meters. He managed to stay at that depth for a full hour.
He ended up dismantling it because it was leaking and had planned on building a second version for the British, but it never happened.
A half a century passed before the next big innovation. This took place during the American Civil War.
The Confederate Navy commissioned the construction of three submarines which were designed by the confederate engineer Horace Lawson Hunley.
The first submarine was the Pioneer, which was built in New Orleans but had to be scuttled after the Union attack on the city.
The second was the American Diver, which was built in Mobile, Alabama, but sunk when it was caught in a storm.
The third submarine was the H. L. Hunley, which was posthumously named after Hunley when he died in 1863 and was built-in Charleston, South Carolina.
The Hunley had a crew of eight people, seven of which were for propulsion.
On ??February 17, 1864, the Hunley became the first submarine in history to sink a ship when it sank the USS Housatonic. Five sailors on the Housatonic died, but the Hunley sank after being in the range of the explosion, killing all eight crew members.
The Hunley was raised and sank again, and then raised again and sank again. A total of 21 sailors were killed in the three sinkings. The Hunley was raised for a final time in August of 2000, after being submerged for 136 years.
Submarine development kept making incremental progress at solving its problems.
In 1863, the French submersible Plongeur was launched. It was the first submarine that didn’t require human-powered propulsion. It was driven by compressed air, which also served to provide air to the crew inside.
In 1864, a Spanish submarine named the Ictíneo II was the first to be powered with a steam engine.
The big innovation which finally made submarines practical as a military weapon came from the Irish engineer John Philip Holland. He created a series of four submarines in the last years of the 19th century culminating in what he called the Holland IV.
The Holland IV had the world’s first combined internal combustion, electric propulsion system. It used engineers when at the surface to charge the ship’s batteries, and then below the surface, the submarine ran on battery power.
The US Navy was so impressed, they purchased the Holland IV and commissioned the ship, renaming it the USS Holland.
The diesel/electric submarine was to be the standard propulsion system for submarines for the next 50 years.
The First World War saw the first conflict where submarines saw wide-scale use. German unterseeboot, known as U-Boats, wreaked havoc on shipping in the North Atlantic. Over 5,000 ships were sunk by U-Boats during World War I.
In World War II, unrestricted submarine warfare once again was let loose in the North Atlantic. Over 3,000 ships were sunk by U-Boats. However, antisubmarine warfare had improved as well. A full 70% of the 41,000 German U-Boat sailors were killed during the war.
Submarines proved to be invaluable in the Pacific. Only 2% of the American fleet was submarines, but they accounted for 30% of the ships destroyed by the US Navy in the Pacific. US submarines destroyed 60% of Japan’s merchant fleet crippling its ability to get necessary resources for the war.
The war also saw the deployment of SONAR which allowed submarines to detect and hunt down other submarines.
The next major advance in submarines came in the early 1950s. Admiral Hyman Rickover, of whom there will be a future episode, advocated the creation of nuclear power submarines.
A nuclear-powered submarine radically changed everything about a submarine and eliminated many of its weaknesses.
For starters, a nuclear power plant doesn’t require oxygen for combustion, so it never needs to surface to charge batteries. It can create its own oxygen onboard the ship via the electrolysis of water, likewise, it can produce its own freshwater from the sea.
Oxygen scrubbers can remove CO2 from the air.
Basically, the only thing which limited the amount of time a nuclear submarine could stay underwater was the amount of food on board.
On January 15, 1955, the USS Nautilus set sail from New London, Connecticut, becoming the first nuclear-powered ship in history.
It immediately began smashing every record for submarines. Its first trip was from New London to San Juan, Puerto Rico. It traveled the entire distance of 2,200 kilometers or 1,400 miles in under 90 hours, breaking the record for the longest underwater journey, and the fastest sustained underwater journey.
On August 3, 1958, the Nautilus became the first ship in history to sail to the geographic North Pole, and it did so under the ice.
In 1960, the Nautilus’s sister ship, the USS Triton, became the first submarine to circumnavigate the globe completely underwater. The journey took two months.
The record for the longest underwater duration by a submarine was set in 1983 by the British HMS Warspite which spent 111 days submerged.
The advent of nuclear submarines created a new category of vessels: the strategic submarine.
The strategic submarine wasn’t designed to hunt other ships. In fact, its job was just the opposite, to remain hidden, as it carried nuclear missiles. A strategic submarine could launch missiles from anywhere in the world, making it almost impossible to counter with a first strike.
Both the Americans and the Soviets used strategic nuclear submarines for almost the entirety of the Cold War. France, China, India, and the UK have also deployed strategic submarines as well.
The performance limits of modern submarines are far beyond what they were 50 years ago.
A Los Angeles class nuclear submarine could in theory dive to a maximum depth of 900 meters or about 3,000 feet. This would really be pushing the safety limits at this depth.
Likewise, a Los Angeles class submarine can travel at a top speed of 32 knots or 59 kilometers/hour.
While the majority of submarines are for military use, there are some civilian submarines. Some are used for tourism, and they don’t go very far beneath the surface. Others are for industry use, for doing repairs and inspections at oil platforms.
In 1960, the Trieste was a civilian research submarine that managed to go to the lowest point in the ocean, Challenger Deep at the bottom of the Marianas Trench.
This type of submarine is known as a bathyscaphe. The unique thing about its design is that the inside of the hull was filled with gasoline. The reason for this is that gasoline is lighter than water, and it is almost impossible to compress.
It took the Trieste 45 minutes to descent 35,000 feet, and then three hours and fifteen minutes to return to the surface.
There has been some discussion of the creation of merchant submarines. For the most part, they could never possibly compete with surface transportation on price.
However, they could be used for two purposes. The first would be to bypass naval blockades to get supplies in restricted areas. Drug cartels have actually used small submarines for exactly this purpose for decades.
The second would be to travel quickly between Asia and Europe under the Arctic Ocean. One possible use would be a submersible oil tanker that would service oil fields above the Arctic Circle.
The submarine was the rare invention that was envisioned thousands of years before it was actually built. Even then it took decades to perfect to the point where it could practically be used. Today, they are a vital part of any modern navy.