How a Nuclear Submarine Reactor Works: S9G Explained #Shorts

Added: 2026-06-02

[00:00:00]A reactor the size of a living room powers a 7900 ton warship for 33 years without refueling. Here's how the S9G does it.

[00:00:12]At its core, the S9G is a pressurized water reactor. Highlyenriched uranium fuel heats primary loop water held above 2,000 ptila C. Hot enough to glow but kept liquid by pressure.

[00:00:29]That superheated water flows to a steam generator, boiling a separate secondary loop into steam that spins the turbines driving the propeller. Here's the S9G's quiet trick. Natural circulation.

[00:00:43]Hot water rises, cold water sinks. No coolant pumps needed at cruise speed. No pumps means no pump noise.

[00:00:55]Reactor power is controlled by halfneeium control rods. Drop them deeper into the core to absorb neutrons and slow the chain reaction. Lift them to ramp up.

[00:01:08]The fuel core is engineered to last the submarine's entire 33 years service life. No midlife refueling, no cutting the hull open. That's a Navy first.

[00:01:21]Quiet, compact, and basically endless.