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More Submarine FAQ's

More Submarine FAQs

Q. What does sonar sound like?

Active sonar makes sounds very much like the "pings" you've heard on TV programmes or in films. Submarines don't usually use "active" sonar as this can give away their position. Instead they use "passive" sonar; passive sonar only listens, so no noise is put out into the water.

Q. Can you hear whales, dolphins and other sea creatures?

Yes. Modern Sonars are designed to enable us to listen for other man made noises such as ships or other submarines; but they are also able to hear the natural sounds of the sea, these are referred to as "Bio".

Q. Where do you sleep?

On British submarines there is an area set-aside as the "bunk space", which contains all the beds or bunks for the crew. Each bunk is approx. 2 metres long by 1 metre wide by 1 metre high, and is often shared by two men who are in different shifts or "watches". The principle is; as each man gets up to go "on watch" he rolls up his own sleeping bag, and rolls out the sleeping bag of the man coming "off watch". During the normal operations of a submarine the sleeping area will only be lit by dim red lights, so as to enable the off watch sailors to sleep. The only man who has his own room, or cabin, is the Commanding Officer.

Q. How do you get air on a submarine?

A submarine obtains air in two ways: bringing it in from the outside whilst on or just below the surface or making it from seawater. When on the surface or at periscope depth, the submarine will "suck" air in through its "induction" system, which is a mast that is raised and then operates just like a swimmers snorkel. To produce air when underwater, the submarine uses machines that take in seawater and break it down into hydrogen and oxygen (water is H2O). The hydrogen is discharged back into the sea, while the oxygen is used to allow the sailors to breathe.

Q. Who does the laundry?

As fresh water is at a premium on board a submarine, the use of the washing machines is strictly controlled, and only certain members of the crew are allowed to operate them. Therefore the normal laundry routine is; each day will be for a specific item of clothing e.g. Monday - Overalls Tuesday - Working clothes.

Q. How do you communicate with the outside world?

Submarines use specialised radios and aerials that can communicate with shore bases and other ships, either directly or via a satellite. The submarine can communicate either by voice or by written word.

Q. How do you get letters on a submarine?

Letters and parcels addressed to a submarine while it is at sea are forwarded to the next port they are scheduled to visit. If a submarine is on an operational trip then it is sometimes possible for short messages to be sent at specific times; these "familygrams" are about 40 words long and each sailor from the CO to the most junior sailor gets the same amount.

Q. Can you get e-mail on a submarine?

With today's technological advances, it is possible to send e-mails to the submarine whilst it is alongside in harbour. The Royal Navy is investigating the possibility of expanding the e-mail connection to the submarine at sea, but only if this is possible without compromising submarine security.

Q. How do you get rid of waste on a submarine?

Submarines store their waste until a suitable time alongside, when they dispose of it as we dispose of any waste in our own homes. If there is no opportunity to dispose of waste ashore, then there are International laws sets down for the disposal of waste at sea. Any waste that cannot be disposed of at sea is stored and removed at the next port visit.

Q. How long does the nuclear fuel last?

Nuclear fuel has an indefinite life, due to the decay rate of radioactive products. However when fitted to the propulsion system of a submarine, the fuel is renewed at every "re-fit", which is when the submarine receives a major overhaul. Each submarine is expected to receive a re-fit every 5 -7 years.

Q. How safe are Nuclear reactors onboard?

Safety is a submarine's top priority. The submarine is designed and operated to ensure that the crew, the public, and the environment are protected from the risks of radiation. The ship is designed with "shielding" around the reactor to reduce radiation levels. Radiation levels are very low, so much so that a submariner gets less radiation at sea than a person on a beach receiving radiation from the sun and other natural sources.

Q. How does one escape from a sinking submarine?

British submarines have two escape routes called "towers", which can be used to escape from stricken submarines. These towers are located at each end of the submarine so that all personnel have access to one or the other. The sailor gets into the tower dressed in a special escape suit, shuts the door, floods the tower with water, the outer door opens and the sailor floats to the surface. The special escape suit, is an all in one waterproof overall, that has a built in hood that can be inflated to enable the escaping sailor to breath normally on his way to the surface.

Q. How do submarines find their way around?

Submarine Navigators use normal navigational charts just like any other ship, but probably pay more attention to depth of water than most ships. Submarines have computers that know how fast the submarine is going and in what direction. This computer can also sense when the submarine changes direction. Submarines also have an aerial that can use the Global Positioning System (GPS) satellites.

Q. What clothes do you wear when at sea?

The crew of any submarine wears the same working clothes as any other sailor in the Navy. An advantage that submariners have, is, that as they are not exposed to the elements, as much as their counterparts in surface ships, then they don't have the need for lots of warm and waterproof gear, which is a good thing as they don't have much space to store it.

Q. Why are women not permitted to serve on submarines?

Service in submarines is closed to women because of medical concerns for the safety of the foetus and hence its mother. This restriction is purely medical and does not relate to combat effectiveness. The potential risks to the foetus do not arise from hazardous radiation, but from contaminants in the submarine's atmosphere.

The Institute of Naval Medicine (INM) reviewed the exclusion in 1999, as did subsequently both the Defence Scientific Advisory Council and Royal College of Obstetricians and Gynaecologists. Their outcomes supported the conclusions of the INM report, that the exclusion was justified.

Q. How are submarines named?

All Royal Navy vessels are named by a committee of senior officers and civil servants who meet at various times to discuss the naming of new ships and submarines. Things that are taken into consideration are, famous names from Naval history e.g. HMS Trafalgar, the type or class of the vessel e.g. if it is a "City" class frigate HMS Cardiff etc. When all the talking has been exhausted, the announcement will be made and another famous name joins the Fleet.

Q. Can you feel the waves on a submarine?

It depends on the size of the waves on the surface. During normal weather conditions, a submerged submarine will not rock with the motion of the sea. In fact, during moderate storms the submarine remains level at its submerged depth while the waves crash above. In extremely violent storms, like hurricanes or cyclones, wave motion can reach to a depth of 400 feet; though not as violent as the surface, these waves can cause a submarine to roll 5 to 10 degrees either way.

Q. Why can a submarine go quicker underwater than on the surface?

A submarines "tear drop" shape allows it to slice cleanly through the ocean when there is water surrounding the hull. When a submarine is on the surface the water and air mix to create turbulent conditions that produce an invisible "barrier" that pushes against the submarine, thus slowing it as well as causing it to roll and yaw.

Q. How many British submarines have sunk?

The Royal Navy has never lost a nuclear submarine.

Q. What happens to old submarines?

Conventionally powered submarines were disposed of either by selling them to other friendly nations or by scrapping. Nuclear powered submarines are disposed of, by taking them to a port where there are facilities to remove all the equipment that can be re-used. After the removal of all non-essential equipment, the submarine is monitored to ensure that the nuclear power plant is still safe and that there are no harmful emissions. This monitoring will continue until it is decided that the nuclear fuel is safe to be removed and disposed of safely.

Q. Can I visit a submarine?

Yes at the Royal Navy Submarine Museum in Gosport they have an actual submarine that is permanently open to the public. Their website can be found at the link below.

Website: Royal Naval Submarine Museum