Have you ever seen fish in a tank, aquarium, or in the ocean and wondered how they swim? And what would it feel like to be a fish, gliding through the water, seeing all of the interesting and exotic things a fish sees. The ocean covers around 70% of the earth’s surface and is extremely deep in some places. There are parts of the ocean we’ve still yet to explore. For a very long time, the size and depth of the ocean have fascinated people who have watched fish and wondered what it would be like to swim deep into the ocean and move about it freely. But humans can’t explore the ocean as freely as a fish. Can you think of a few things we need and don’t have naturally? To be able to breathe underwater like a fish is one. And a way to move around. Also, the deeper you go the more pressure surrounds you and human bodies can only take so much pressure. For a very long time, people have wondered if they could invent a way to move through the water and for longer periods of time like a fish.
One of the early people to ask questions like this was William Bourne. Bourne was a British mathematician who in 1578 shared his idea for an enclosed boat that could go underwater, be submerged, and also be rowed underwater. This first idea for a submarine would be built of wood and covered in leather which is waterproof. It was a great idea and Bourne shared it with others but it wasn’t until around 50 years later that a dutch inventor named Cornelius von Drebel decided to take Bourne’s plans and build the underwater boat. When it was completed, Drebel’s submarine could go 12 to 15 underwater and was powered using oars that stuck out of the holes in its side. You can imagine how fascinating it would have been to see the first submarine at the time! It made several trials in the Thames River in England and it is believed that King James got to ride in it.
Once others saw Drebel’s idea, they were inspired to create their own submarines and as many as 14 different versions are known to have been created within a hundred years after Drebel’s. With each invention, new ideas were shared about how a submarine could function. Inventions typically work this way. Someone has an idea, others try it out, make changes, and continue to try new things and make changes and share their ideas, working towards the more advanced, modern versions of inventions we have today. This was the same with the airplane and computers, among all of the other technologies we have today.
During the American Revolution, an engineer had the idea to use a submarine to try and disable enemy ships. His name was David Bushnell and he constructed a very basic submarine made of wood and named it the Turtle. Only one person could fit inside it and after submerging it was designed to sneak up beside an enemy ship and then place a bomb on it. When the bomb went off, it would damage the ship’s hull and it would no longer be useful. It was an ingenious idea and the Turtle was able to float under the water and sneakily approach the ship, but once it got next to the ship the bomb attaching device didn’t work. This is the first known example of someone trying to use a submarine during war.
Another famous submarine inventor was American Robert Fulton, who later would go on to create some of the well-known steamships. But before steamships, Fulton was living in France and built a submarine which he called The Nautilus. Napoleon Bonaparte was the leader of France at the time and he paid Fulton to design and build the Nautilus. Unlike earlier submarines, the Nautilus was made of metal: an iron structure covered with copper sheets. The propellers were still hand-powered but it could move above and below water, since above water a mast and sail could be stood up. The Nautilus used a technology called ballast tanks. These tanks would take in water to go down and then push the water out when it needed to go up and float to the surface. It also had a rudder to steer the submarine and four people could fit inside. But this was still an early design, so for light, the sailors still had to use candles!
During the 1800s, updates and new innovations continued to make submarines faster and better at navigating underwater. Eventually, steam and diesel-electric power, and gasoline was used to move the submarines. Engineers also experimented with new ways the submarines could be used in war by firing torpedoes, which are underwater missiles. They also became bigger and could hold more people. The French navy built a submarine called the Narval which was propelled by a steam engine and was 111 feet long!
By the time World War 1, also called The Great War, took place in the 1900s, technology had reached a point that very dangerous submarines sailed the ocean. Germany was known for its powerful submarines called U-boats, which were 300 feet long and could move at 13 knots on the surface and 7 when submerged. It was also armed with torpedoes and guns and was feared by its enemies.
U-boats became even more powerful and dangerous by World War II. Germany built over a thousand U-boats. They were very advanced and moved in groups called “Wolf Packs” which attacked enemy ships moving supplies across the Atlantic Ocean. The United States Navy and others had to find ways to fight back against the German U-boats and eventually succeeded. During the Battle of the Atlantic 41 U-Boats were sunk so for a time they stopped attacking in the Atlantic. During World War 2 785 of the 1,000 German U-boats were eventually sunk.
Later, the United States, Britain, and the Soviet Union began building nuclear-powered submarines, which were powered using nuclear fission, the same process used to power an atomic bomb. They sailed much faster, dove deeper, and used advanced sonar radar that could detect other submarines and ships above water. The Permit-class attack submarine was almost 300 feet in length, the size of a football field if you can imagine that! It could hold around 130 sailors who each had different jobs from captain to radarman, to cook or weapons specialist. They spent many days underwater patrolling the oceans. Can you imagine living underwater in a submarine for that long? These submarines were equipped with powerful weapons, some of them ballistic missiles which could fire up out of the water and enemy targets.
Since that time, submarines designed for warfare have only improved. But today not all submarines are used by the military. Have you heard of a submersible? A submersible is a smaller submarine that is used to explore the ocean and its life. It’s designed to be carried on a ship out to sea and then lowered into the water where it can dive deep and learn more about the depths of the ocean. If you think about it, so much of the ocean is undiscovered which makes it a little like an alien planet, because there are species we haven’t found yet and places we haven’t visited.
One of the most well-known submersible operators was a marine scientist named Robert Ballard. He grew up in San Diego, California, and living near the ocean was fascinated by it. He wanted more than anything to explore it and learned to scuba dive the first chance he got. As he got older, he went to school to learn more about the ocean and also became interested in submersibles. In the 1970s, Ballard helped build a three-person submersible that they named Alvin. Using Alvin, Ballard and his crew dove 9,000 feet to explore an underwater mountain range in the Atlantic Ocean. Did you know there are mountains under the ocean? They used Alvin to explore other places like thermal vents, which had plant and animal life in them, an entirely new discovery for scientists.
The next submersible Ballard and his team designed was called the Argo. But the Argo was special because it was unmanned and could go deeper and longer than a submersible with humans could. It could also send pictures up to the boat of what it was seeing. Ballard decided the main goal of the Argo would be to find the Titanic. If you’ve listened to our episode about the Titanic, you’ll know that the Titanic was a huge ocean liner that was sunk in 1911 after hitting an iceberg. For seventy years no one had yet to find the Titanic. It was in a very deep area of the ocean and they weren’t sure exactly where it lay to rest. It took many days of searching, but on an exciting day in 1985, Ballard and his crew saw images of the Titanic Argo sent to them deep from the bottom of the ocean. It was broken into two pieces and covered with coral and other sea life. But you can imagine how excited they were when they finally discovered the Titanic and were able to share their findings with the world.
Later, Ballard returned to the Titanic in his submersible, the Alvin, so he could see it in person for himself.
If you had a chance to take a voyage in a submersible or submarine would you? Are you interested in learning more about submarines and the ocean? If so, have your parents help you find some books about submarines at the library or find some good videos on the Internet. I loved learning about submarines because it just amazes me what people can do when they put their mind to accomplishing a goal and then get to work. Designing something takes time learning about the science behind it, and then experimenting and making changes until you get it right. This is the engineering process! And like the great inventors and engineers of the past you can start small with your own inventions, too!