submarine

model：FS1500-9 manned submarine

1. Definition and classification
Definition: Submarine is a military or scientific research vessel that can sail underwater.
Classification: According to size and purpose, submarines can be divided into large (mainly military), medium, small (including pocket submarines, submersibles, etc.) and underwater automatic mechanical devices. Large submarines are mostly cylindrical, and a vertical structure (bridge) is usually set up in the middle of the ship, which contains communications, sensors, periscopes and control equipment.
2. Functions and uses
Military use: Submarine plays an important role in the military, with functions such as attacking enemy warships or submarines, near-shore protection, breaking through blockades, reconnaissance and concealing special forces operations. It is a recognized strategic weapon, especially in disarmament or expansion negotiations.
Non-military use: Submarine is also widely used in non-military fields, such as marine scientific research, salvaging property, exploration and mining, scientific detection, maintenance equipment, search and rescue, submarine cable repair, underwater tourism, academic investigation, etc. Super rich people even use it as a mobile mansion under the sea.
3. History and Development
Origin: The history of submarines can be traced back to the 15th and 16th centuries, but the real submarines appeared in the 16th century. With the development of science and technology, the design and function of submarines have been continuously improved.
Important Milestones: Historically, submarines have evolved from human propulsion to mechanical power, and from single function to multi-function. Modern submarines are usually driven by internal combustion engines, electric motors or nuclear reactors, and have the ability to dive for a long time and sail at high speed.
4. Technical Features
Concealment: Submarines have high concealment when sailing underwater, and can avoid being detected by enemy radar and sonar.
Endurance: Modern submarines usually have a long endurance and can dive underwater for weeks or even months.
Powerful firepower: Submarines are usually equipped with weapons such as torpedoes and missiles, which can pose a serious threat to enemy surface ships and submarines.