Being on a sinking ship is probably one of your worst nightmares but not if you’re in a submarine. Sinking is exactly what you want when on board a sub. Submarines are adept at sinking and slipping quietly along under the waves. They have an image of being mean, lean fighting machines and can stay hidden and undetected for weeks and even months at a time. So, what makes them sink?

Oceans are pretty turbulent places and ships will often pitch and roll, struggling to rise and dip in between each crashing wave. Life is much calmer under the surface but of course things then get dark, airless and there’s lots of pressure. Submarines are an incredibly genius method of transporting people through these harsh and extreme environments. Most are built for military purposes but there are some whose primary purpose is scientific research.

A typical submarine will have some key parts which include a pressurized hull. The water pressure is a big issue for underwater travel especially when you consider that at a depth of 2000 ft, the maximum dive depth for a sub, water pressure is 60 times greater than it is at the surface. Submarines will usually have two hulls, one inside the hull as an extra protective measure. The outer one is waterproof whereas the inner one is much stronger and called the pressure hull. The inner hull is extremely resistant to water pressure and will be made from titanium or steel. Submarine parts have to be incredibly tough and preferably water resistant. For Silicone hose manufacturers, visit

Submarine designers have looked to nature for engineering the ability to dive. Just as sharks have fins, submarines have diving planes or hydroplanes. They work a bit like wings on an airplane with the ability to create an upward force called lift. While underwater, the sub is negatively buoyant and static. When it starts to propel forward, water rushes over the planes and creates the upward lift force. This enables it to remain at a constant depth, creating a state of neutral buoyancy or floating. Further control is achieved over buoyancy with the use of ballast tanks. Spaces between the two hulls can be filled with either air or water to help float or sink the machine as required.

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Fuel is another issue as most engines require oxygen to make them work but as there is no oxygen underwater, submarines have to rely on diesel-electric engines unless they are nuclear powered. The diesel engine operates fairly normally when near the surface but doesn’t drive the propellers directly. Instead, it powers up an electricity generator which in turn charges up massive batteries. Once they are fully charged, the submarine can drop below the water and rely entirely on the powered up batteries.

The iconic cigar shape gives the submarine the ability to slip smoothly through the water. The centre does hold a tower though which is where you’ll find all the navigation equipment. Due to the extremely dark conditions, most subs have a periscope, which are only useful when the sub is near the surface. So they rely on GPS and SONAR which is similar to radar. Inertial guidance is also used which is a way of keeping track of distance and direction using gyroscopes.

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