What are Submarines ?

In theory, it should be much easier for ships to swim under the waves where the water is calmer and puts up less resistance; in practice, that creates a different set of problems.

The British submarine HMS Artful can stay submerged for 25 years without having to surface for air.

We would have to tie a heavy stone to it to make it sink at all. This can would also sink and sink, but when it reached the bottom, it would be completely crushed, if it didn't burst. The air would be compressed into a tiny bubble.

If you've ever gone snorkeling or scuba diving, you'll know that life underwater is very different from life on the surface. It's dark and difficult to see, there's no air to breathe,

They are lean, mean, military machines and they can stay submerged for weeks or even months at a time. Let's take a closer look at how they work!

One of the checks which a British nuclear submarine makes to see whether the government is still functioning is whether BBC Radio 4 is broadcasting.

intense water pressure makes everything feel uncomfortable and claustrophobic.

You can try this on your own. Take a full water syringe and push your finger hard on the opening. Then try to push down the plunger. It can't be done. Now squeeze out the water, put your finger on the hole and try the experiment when the syringe is full of air. You will notice that you can push the plunger in to some extent, depending on how hard you push and how strong you are.

In the 1960’s, for fear of having their submarine communication cables cut by the Soviets, the US military sent 480,000,000 copper needles into space to secure their communications infrastructure. The needles acted as a mirror for radio waves, enabling communication between distant sites.

The UK has 4 nuclear submarines as a nuclear deterrent, each has an identical letter of last resort. These letters contain orders from the current PM should the government collapse due to nuclear attack. The PM has only four options to choose and they’re destroyed unopened upon a new PM.

Submarines are ingenious bits of engineering designed to carry people safely through this very harsh environment.

In 2009, two nuclear submarines (French and British) collided with one another in the Atlantic because they couldn’t detect one another.

Although they were originally invented as military machines,

A Japanese submarine shelled California during WWII and the commander directed his gun to fire at a spot where he had an embarrassing fall before the war.

most large subs are still built for the world's navies, a few smaller subs do work as scientific research vessels.

the worst thing that could ever happen to you on a ship in the middle of the ocean would be for water to flood in and make you sink. But if you're on-board a submarine, sinking is exactly what you want! Unlike ships, which pitch and roll as they struggle across the waves, submarines slip swiftly and silently through the calmer waters beneath. They are lean, mean, military machines and they can stay submerged for weeks or even months at a time. Let's take a closer look at how they work!

Submarine ahoy! When we see photos of submarines floating on the surface, it's hard to imagine how big they really are: like icebergs, virtually all of a floating sub is underwater..

In 1998, an entire North Korean submarine and her crew were lost to a single South Korean fishing net. A WWI submarine washed ashore on the beach at Hastings, England.

In this very unusual picture of a submarine in dry dock for maintenance, you can clearly see how big a submarine really is—and that it really is almost a perfect cylinder

Photo: Submarine ahoy! When we see photos of submarines floating on the surface, it's hard to imagine how big they really are: like icebergs, virtually all of a floating sub is underwater. In this very unusual picture of a submarine in dry dock for maintenance, you can clearly see how big a submarine really is—and that it really is almost a perfect cylinder. Photo of USS City of Corpus Christi at Pearl Harbor Naval Shipyard by Dustan Longhini courtesy of US Navy.

In October of 1981, a Soviet Whiskey-class submarine ran aground on the south coast of Sweden. This incident became known as Whiskey on the rocks.

Most of these are submersibles (generally small, unpowered, one- or two-person submarines tethered to scientific research ships as they operate).

4 people died and 43 were captured because someone didn’t know how to operate a submarine toilet.

The pressure of water pushing inward is the biggest problem for anyone who wants to go deep beneath the ocean surface. Even with scuba tanks, we can dive only so far because the immense pressure soon makes it impossible to breath. At a depth of 600m (2000ft), the maximum depth subs ever dive to, the water pressure is over 60 times greater than it is at the surface!

How do subs survive where people can't? The hull of a standard ship is the metal outside that keeps the water out. Most submarines have two hulls, one inside the other, to help them survive. The outer hull is waterproof, while the inner one (called the pressure hull) is much stronger and resistant to immense water pressure. The strongest submarines have hulls made from tough steel or titanium.