Changes

Submarines played a significant role in both World Wars I and II, and to this day many nations have submarine fleets, varying from the large, highly trained nuclear fleets of the United States and the United Kingdom, to countries owning one Kilo class diesel submarine.

Submarines played a significant role in both World Wars I and II, and to this day many nations have submarine fleets, varying from the large, highly trained nuclear fleets of the United States and the United Kingdom, to countries owning one Kilo class diesel submarine.

[[File:Virginia class submarine.jpg|thumbnail|300px|center|In the United States, the submarine force is often referred “The Silent Service” because of how it operates. Submarines can submerge more than 600 feet below the ocean's surface for up to four months at a time, constantly patrolling and working classified missions.<ref>[https://www.uso.org/stories/3060-what-you-should-know-about-the-u-s-naval-submarine-force What You Should Know About the U.S. Naval Submarine Force], United Service Organizations (OSO) website<ref> ]]

[[File:Virginia class submarine.jpg|thumbnail|300px|center|In the United States, the submarine force is often referred “The Silent Service” because of how it operates. Submarines can submerge more than 600 feet below the ocean's surface for up to four months at a time, constantly patrolling and working classified missions.<ref>[https://www.uso.org/stories/3060-what-you-should-know-about-the-u-s-naval-submarine-force What You Should Know About the U.S. Naval Submarine Force], United Service Organizations (OSO) website</ref> ]]

 

==Power sources==

==Power sources==

Various different power sources have been used on submarines over the years.  The ''Hunley'' was powered by its crew turning a crank which was connected to the propeller.  [[Gasoline|Petrol]] engines have also been used, but they gave way to [[diesel engine]]s.  The petrol or diesel engine drives a [[generator]], which charges a [[Battery (electrical)|battery]], and the battery supplies an [[electric motor]] which propels the submarine.  The petrol or diesel engine can only be run when the submarine is on the surface, to recharge the battery.  

Various different power sources have been used on submarines over the years.  The ''Hunley'' was powered by its crew turning a crank which was connected to the propeller.  [[Gasoline|Petrol]] engines have also been used, but they gave way to [[diesel engine]]s.  The petrol or diesel engine drives a [[generator]], which charges a [[Battery (electrical)|battery]], and the battery supplies an [[electric motor]] which propels the submarine.  The petrol or diesel engine can only be run when the submarine is on the surface, to recharge the battery.