Naval Historywith Dr. Alex

Q&A · 54:38-55:48

Why nuclear submarines tend to be large

Nuclear submarines tend to be large because of the long-range missions assigned to them, not simply because a reactor demands the largest possible hull.

Attack SubmarinesNuclear PropulsionSubmarinesT Class SubmarinesU Class Submarines
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Question

Does the size of nuclear submarines show that reactors only make sense in very large ships?

Short answer

No. Nuclear submarines are often large because they perform long-range attack and patrol missions, so their size reflects the role as well as the propulsion system.

Notes

Most modern nuclear submarines perform long-range patrol and attack missions that require substantial weapons, sensors, endurance, and habitability. Those roles are compared with the Royal Navy's wartime T-class submarines. Modern conventional submarines more often fill shorter-range jobs analogous to the smaller U class. The size difference therefore reflects mission as well as machinery. Nuclear propulsion should be judged against what the boat must do rather than treated as a technology reserved automatically for any very large warship.