What is a big advantage with nuclear submarines compared to diesel fueled submarines?
Diesel boats have to come to the surface periodically so that they can run the diesel engine and recharge their batteries. On the other hand, when a nuke submerges, it doesn’t have to come back up until it runs out of food for the crew. The diesel boats have an advantage in that they are significantly quieter when they are running on their batteries. However, they become much more vulnerable when they are the surface recharging because they are close to the surface and the diesel engines are noisy. With a nuke, the reactor does make some rather soft noise, but they can stay down deep where that little bit of extra noise is hard to hear.
