Submarines

The actual diving depths of most modern nuclear submarines is highly classified; however, all submarines are constructed to either withstand the pressure (e.g., the titanium hulled Russian ALFA), or "flex" with the pressure. It is the metallurgical properties of the steel used that determines how well a submarine's outer and inner hulls withstand the enormous pressure per square inch at deep depths.

While strong hulls like the ALFA mean they can go deeper, the fact that they don't flex with the pressure (contracting and expanding as it goes deep and then shallow) makes the hull more brittle with each dive. It is similar to an eggshell being repeatedly put under stress - since it cannot flex, it will eventually break.

By contrast, U.S. Submarines are built with a specific type of steel that contracts with pressure, and expands. A little known fact of submarine construction is that the decks are actually "floating" - they are suspended and do not actually touch the hull for this reason.

To illustrate the extreme pressures at deep depths, during the first operations on the wreck of the USS Thresher (SSN-593), a styrofoam coffee cup was placed in a basket of the bathyscape that was used to survey the wreck. Placed outside the hull, it was subjected to the extreme pressures of the deep ocean. When they returned to the surface, it had shrunk from its original size (around 6") to barely the size of a thumb due to the compressive forces of the sea. This is still done on civilian research submarines and ROV's for souvenirs.

A submarine's hull shape is also designed specifically to deal with deeper depths. The submarines of WWI and WWII were not considered true submersibles by today's standards - they were surface ships with limited submerged operational capability. As such, they were designed to run faster on the surface than submerged, and their design wasn't truly made for extreme depths.

It has been long known that a spherical, or round shape, is the best shape for withstanding pressure. This is why the earliest diving bells, diving hard hats, and rescue chambers all had spherical designs. Today's rounded hull shapes of modern submarines allow them to go much deeper and withstand a lot more pressure than their older counterparts.

Wolfpack

Modern submarines rely on their hull design and material construction to deal with extreme pressures in the ocean while submerged. Most NATO countries use a flexible, compressible steel alloy that allows the hull to compress and expand as the submarine goes deep and shallow. The decks aren't actually connected to the hull - if they were, they'd be severely damaged as the boat goes deep. They're actually suspended by cables, the sides of the decks several inches from either side of the hull to prevent contact.

Not all submarines use this type of construction, and it can be a problem later down the road in the life of the boat. For example, the Russians have used Titanium to construct some of their boats. While strong and allowing them to go deeper, Titanium isn't flexible, and over time under repeated pressures it will become brittle. Others like China use GRP (fiberglass) to construct their boats. The problem with having non-flexible material is the egg-shell effect - egg shells are strong, but under enough repeated pressure they become brittle because they cannot compress and expand.

A spherical based design is also the strongest for extreme pressures, and why virtually all modern submarines are based on a cigar or teardrop shaped hull design.

In the US Navy, we all eat food from a standard set of recipe cards. If you google search Armed Forces Recipe Cards or NAVSUP P-7 recipe directory you can see the individual recipes. Submarines have a corps menu that uses these recipes.

U-96, whose emblem was a green laughing sawfish

They didn't for unrestricted warfare. For restricted warfare they surfaced, got out a loud speaker and addressed the ship's captain. Such as, "You have 15 minutes to evacuate your vessel, then your ship will be sunk." Or...for the wise and experienced sub skipper (sub captain), "you have 15 minutes to evacuate your vessel, then we will sink your ship. IF you transmit any messages commencing now, we will sink you immediately!"

Diesel-Electric submarines use diesel fuel to run their diesel-generators, which provide power to charge their batteries for submerged operations. Nuclear-powered boats typically use a uranium core with a pressurized water configuration. The Russians have also experimented with liquid metal rather than water (bismuth).

a submarine has a water tank. when the tank is filled then submarine sink in the water. and when the tank is empty then submarine float in water.

use the formula density= mass / volume

as mass increases(when the tank is full of water), the density of the submarine increases and it submerge into the water and vice versa.

naval submarines do not have a thing to do in those lakes but the recovery submarine type robot that searches ocacionally is brought to seek for sunken vessels in the past.

you cant see them under the water and so they can attack without being seen.

There are ballast tanks in a submarine. If the submarine weighs 150,000 pounds, it will push aside, or displace, 18,750 gallons of water. (We're using an even 8 pounds per gallon here.) If the submarine's volume is actually 25,000 gallons, part of the submarine will be out of the water--what we call floating.

To make the submarine submerge, you must increase its weight to 200,000 pounds--the same as 25,000 gallons of water. This is done by pumping water into tanks in the front and back of the submarine. Once they do this, the whole submarine will be underwater and they can control its depth with planes. They can also "trim" the sub by putting more water in one tank than in the other. Submarines change their weight distribution all the time. If you put a case of canned peaches in the front of the boat when you were provisioning it for the mission, and you fed the peaches to the crew, you've got to compensate for the loss of that case of fruit by adding a little more water to the forward ballast tank. That's how sensitive these things are--you have to compensate for the food you eat to make them ride right. (And if you actually have to shoot at anyone you have to compensate for the torpedos or Tomahawk Missiles you fired.)

Increasing the weight of a submarine beyond its displacement will make it sink to the bottom. You might want to do that if you were going to park the boat at the entrance to a harbor and wait for a ship to come by so you could block the channel by sinking it, but if you did it all the time you'd have to waste lots of power keeping the boat off the bottom.

The name U-boat was applied to German submarines.

The average crew complement is between 90-130 Officers and Enlisted. However, on long deployments or sea trials, that number can approach 150 or more with the full crew aboard as well as civilian riders (military contractors, shipyard workers, etc.) and other military / government personnel aboard.

The most powerful submarine to date is the Akula (or NATO designation Typhoon) class boat, first launched in 1986 by the Russians. It has a maximum displacement of 12,770 tons submerged (for the Akula II).

Answering a most-powerful-millitary-vehicle/aircraft/ship is sometimes hard because a given piece of hardware might be longer, but lighter, etc. Certainly each piece of equipment has advantages and disadvantages over another, but, this submarine has the largest maximun load capacity. It has the greatest shaft horsepower rating, too. A link is provided below for more information.

25,000 tonnes

Currently, women have to have their own toilets and beds. Consequently, architects are going to have to design bigger and more expensive submarines to acommendate those extra rooms, beds, and toilets. In addition, supply officers are going to have requisition SPECIAL hygiene material, as well as find storage facilities on board the submarine to maintain them.

The first diagram and plan for a submarine was published in 1580 CE by William Bourne. In 1623, Cornelius Drebbel was appointed as court inventor and created what is believed to be the first working submarine. In 1654, the Rotterdam boat submarine was invented with the intent to attack an enemy. In 1696, Denis Papin built two submarines with an internal air pump. In 1776, David Bushnell created the first submarine that attacked an enemy ship. In 1855, Wilhelm Bauer built the Diablo Marin which made 134 dives. In 1861 the U.S Navy commissioned the production of the Alligator submarine.

They are in various locations around the vessel. normally ( S-boat standard War II type sub ) there are 8 live or usable tanks- the diving sequence is almost always- following the Command- Take Her Down!- Flood l,3,5, and 7, these are the odd numbered tanks located in the forward part of the vessel. Ballast tanks contain water and air- the air used to blow them out for surfacing. do not confuse with fuel tankage. German practice in attacks was to submerge the U-boat mainly on the diaplanes ( Dive planes) and avoid the use of flooding ( this was in the Atlantic or ETO) they were probably afraid of a runaway dive if they used the Ballast tanks. a translated technical manual intended for Sub officers ( German) bears this out. Allied subs were taken down on BOTH the diaplanes ( normally down angle did not exceed 29 degrees) and the Ballast tanks. the Germans preferred using the diaplanes only ( like a fish). so it goes.

Average: 20 knots surfaced 09 knots submerged

In US submarines, the ships internal navigation system (SINS) uses gyroscopes. The gyros in the SINS keep track of the location of the submarine by following course changes (detected by the gyros) and time and speed on a given course. Crunch all the numbers after entering your starting coordinates, and the SINS will tell you where you are at any given time. And if you happen to get a rock solid fix by whatever means, you can compare it to what the system says. You can also "reset" the system based on your new data.

If the submarine was 60 meters below the surface and the plane was at 340 meters above sea level, the missile would travel 340 m + 60 m or 400 meters to hit the plane.

In and around Sydney Harbour