Submarines

There have been many sizes of submarine from the tiny British X-boats weighing about 6 tons to huge 'boomers' weighing over 8,000 tons

200 ft

They use a periscope. See the related link for more information.

During WWII, the US GATO class (the Balao was a GATO with interior changes).

The largest current American subarines are the Ohio-class Trident ballistic missile submarines, measuring 560 feet in length and displacing over 16,000 tons.

He declared war.

Submersibles are used for exploring underwater life fartherbeneath the surface then humans can go UNequipt. John Wikes Booth invented the submersible. Its is also a small nonmilitary nonnuclear submarine that is used for exploration.

in 2050

Sorry, but that information is classified.

Naval submarines do not dive deep enough to go near underwater mountains. This is contrary to what you may have seen in the movies. They use sounding charts to determine the depth of the water in which they are navigating. They avoid such underwater objects. Research submarines use cameras and sonar, as well as charts, to guide them.

The U.S. Navy's Trident submarine refit/resupply base is in King's Bay, Georgia.

Keeping a submarine warm is the easy part; with all of the electronic equipment, electrical systems, and engineering/propulsion systems, it gets pretty toasty, even in Arctic waters. It's keeping everything cool so that systems don't overheat that's difficult.

There is no recoil. Torpedoes are launched by one of two methods: either by water impulse (primary) or by motor startup within the tube.

Impulse is achieved when the water in the in the torpedo tube contacts one side of a piston ram that is located in a separate chamber below. An air flask dumps compressed air into the other side of the piston, forcing the water and torpedo out of the tube simultaneously, where the motor starts. Since the tube is flooded prior to impulse, it's equalized to the sea pressure of the depth the submarine is at. The force of the impulse isn't even close to the force necessary to affect an opposing force on a submarine.

If the impulse system isn't working, the tube can be flooded and the motor can be started in the tube and the torpedo can exit on its own.

All modern torpedoes have their own active/passive location-and-tracking sonars; once they've got a dead lock, you're history, unless you're in a boat or ship that can outrun a torpedo that is traveling toward you at 55 knots.

The submarine was the first to be invented, but was also the last of those three to be developed into an effective vehicle.

Gives governments more options. SMs can be where they say they're not or may not be where they say they are. Complicates the problem for aggressors.

HY80 steel and variants, a flexible steel alloy, has for decades been used on modern U.S. and Allied submarines. Its flexible properties are what makes it an asset - it contracts and expands as sea pressure increases/decreases with submerged operations. Internal submarine decks are not actually attached to the hull - they're actually hanging from from suspended cables and the decks are several inches from the sides of the hull to allow for the contraction as the boat goes deep.

About 25 years ago, there was a lot of controversy about the Russian ALFA class Fast-Attack and her known Titanium hull, able to reach depths near 3000'. Many in Congress wanted to know why the U.S. didn't have something similar. Fortunately, idiots remain in Congress and Engineers design Nuclear Submarines.

Titanium is extremely strong, but it is not flexible - sure, the ALFA can dive deep, but each time it puts stress on the hull when it deep-dives it becomes more brittle over time. It's like putting increased pressure on an eggshell - eventually it'll crack. This doesn't happen with HY80. It remains flexible over decades and hundreds of dives and surfaces.

Also, you don't need a submarine that can go to 3000'. All you need is a weapon that'll go to 3000'. At that depth, even minimal damage to the pressure hull would result in a major casualty and likely loss of the boat.

yes

Compressed air is used to push the water out of the ballast tanks. This makes the submarine overall less dense than the surrounding seawater, and makes it rise to the surface. The same technique is used to change depth upwards, and can be stopped before the surface is reached.

air pressure

because if air is lighter than water and you are trying to get a tank full of water to sink you would need a whole lot of air so by compressing lots of air into the tank it makes the tank heavy so it sinks

The 'galley' is the kitchen area on submarines

The term actually is a sailor's nickname, and is derived from the old WWI/WWII submarines. Prior to the advent of Nuclear Power which allowed for unlimited potable water production, submarines carried a limited supply of water to sea with them, and that was primarily used for drinking water and basic sanitation. Luxuries like showers were few and far between, and the cramped, hot living conditions aboard those boats led to some pretty smelly sailors after several weeks.

Even today, though there is plenty of water available aboard, the smell from the various chemicals used aboard tends to permeate clothing, leading to its own unique smell among submarine crews.

U-boats (Unterseeboot)

All the sailors in it die.

Yaw, Pitch and Roll on a submarine is no different than it is for an aircraft. The only difference is the medium in which both travel, i.e., water vs. air. But the principles of ascent and descent, and turning are the same.

Roll is a lot different of course, as submarines are very stable platforms when submerged. However, nature is a very powerful force. I remember one time in particular when we were submerged at 400', and taking 12 - 15 degree rolls due to a surface hurricane passing over us at the time. Submarines do not take rolls very well - or should I say, the crew doesn't. Submarines, though they do of course roll, aren't designed to take extreme rolls like ships or aircraft, so when they are subjected to forces that make the roll any significant degree, it's sorely felt by the crew.

The WWII Gato class US sub carried 24 torpedoes.