You may have seen a submarine on television or in the movies.
This large, powerful underwater vessel is a cool way to explore below the sea.
We also depend on them for many things.
Read on to discover all about the submarine. We will be exploring the history of the “sub”, what it is used for, and much more.
So let’s dive right in and discover the world of the submarine.
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Submarine Facts for Kids
- Submarines use sonar radar to navigate under the water
- A submarine has ballasts to ensure it rises and sinks with ease.
- They can dive to thousands of feet below the surface of the ocean.
- They can remain underwater for several months
- Subs were a part of the American Civil War.
- 1954 saw the launch of the first nuclear submarine
- In World War I and World War II, the Germans used subs called U-boats to attack Allied Forces.
What is a Submarine?

A submarine is a special vessel or ship that can go underwater. Inside has huge tanks that hold water. These are called ballast tanks.
The sub comes equipped with a power source. These can be an engine, nuclear power, batteries, or a combination of the three.
To find its way through the dark oceans, submarines use sonar equipment.
This puts out a sound wave.
When a sound wave hits an object it bounces back a signal to the submarine.
Other equipment inside the submarine provides clean water and air for the crew members.
The History of Submarines

Oddly enough, the first working submarine was actually a leather-covered rowboat.
An inventor by the name of, Cornelis Drebbel constructed this odd underwater vessel in 1620. It managed to reach depths of 4.5 meters (15 feet).
In 1776 a US inventor (David Bushnell) built a submarine that was used in the American Revolution. Later on in the year 1800, another American inventor (Robert Fulton) built the Nautilus. This submarine was small and was used for attaching explosives to ships.
By the 1900s, inventors had come up with subs that could run on a battery-powered electric motor (for underwater) and diesel engines (for surface traveling). These submarines were used in both World War I and World War II.
In 1954, the US Navy used the first nuclear-powered submarine. It was named the USS Nautilus.
How Does a Submarine Submerge?

Air is used in ballast tanks to keep submarines at surface level. During submersion, the valves on the ballast tanks are opened.
When the air escapes, seawater fills up the tank. It makes the sub heavier, and then it submerges.
A submarine is driven by four people either on the surface or submerged. Pilots control the rudder and diving planes using controls to steer left and right.
The diving officer is the person who is responsible for supervising the divers. One of the four watch team members sits near the Ballast Control Panel (BCP) and runs it.
The Ballast Control Panel controls the ballasts, which floats the boat when submerged and maintains the trim when it’s submerged.
How Does a Submarine Surface?

The process of blowing to the surface is one way in which a submarine can surface.
Seawater is replaced with high-pressure air in ballast tanks. Water weighs down the sub, so displacing it makes it climb to the surface.
You can also raise the submarine as you cruise by angling its stem, bow, and superstructure.
Once on the surface, low-pressure air can be used to force seawater out of the ballast tanks against gravity so that the vessel remains above the water.
How Deep Can You Go in a Submarine?
The navy prefers to keep some details Top Secret. Navy submarines can dive to a depth of over 800 feet. However, they don’t dive quite as deep as the research subs.
A section in the Mariana Trench known as the Challenger Deep is regarded as the deepest point in the world’s oceans. Research subs have been to 10,000 meters deep.
The Caribbean Sea depth averages 2,200 meters or 1.3 miles. The average depth of the world’s oceans is 3,790 meters.
How Long Can Submarines Stay Underwater?
Navy subs powered by nuclear-power can remain underwater for 25 years. But the reality is food on submarines lasts 90 days, so they stay underwater for three months typically.
Air is not an issue as they create their own oxygen. Their only limit is food and supplies.
I’m sure the crew on the sub couldn’t last 25 years.
It’s All About the “Ballasts”
In order for a submarine to stay submerged (underwater), it has special compartments called, ballasts. These huge tanks fill up with water when the sub wants to sink.
This is because with more water it becomes heavier and will sink. When the submarine wants to rise, the water in the ballasts is let out.
This makes the vessel lighter so it rises. A sub also has a propeller on the back of it. This pushes it at various speeds.
What Are Submarines Used For?
You might be surprised at all the things a submarine is used for. Check out the following list to see which ones you knew.
Military – subs protect the Navy’s ships (aircraft carriers) and carry out other tasks.
Science and Research – subs are helpful for studying the depths of the oceans where divers cannot reach.
Salvage – subs can be used after a ship sinks to recover lost items.
Tourism – some exotic locations offer rides in a submarine.
Fun Submarine Facts for Kids
- The one submarine that cannot go underwater is the submarine sandwich? It would get really mushy and taste disgusting.
- In 1870 Jules Verne wrote the classic novel, 20,000 Leagues Under the Sea?
- Specialized submarines can reach depths of 4,498 meters (14,760 feet)?
- Nuclear submarines can hold up to 100 crew members?
- The long narrow body of a sub is called, the hull?
- When a submarine needs to see what’s going on above the water, they use a periscope? This is like a single binocular-like eyepiece.
- The submarine has a “raised deck?” When the vessel rises to the surface, crew members can stand on top of it.
- The Beatles had a song called The Yellow Submarine
Now that you have learned all these fascinating facts, you can impress your friends and family with your new-found knowledge.
Who knows?
You might just become known as “Captain Sub.”
Just don’t let them think you’re a sandwich.
