Naval Historywith Dr. Alex

Q&A · 3:02:08-3:13:10

A four-shaft Nelson-class design at 28 knots

Adding shafts and boilers to the Nelson design shows how machinery arrangement and resistance thresholds govern battleship speed.

BattleshipsFast BattleshipsNaval PropulsionNelson Class BattleshipsShip Design
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Question

How fast could Nelson and Rodney have been with additional shafts and matching machinery?

Short answer

A properly designed multi-shaft version might reach about 27.5 to 28 knots, but only with the hull form and power plant developed together.

Notes

Using the available displacement margin for more shafts, boilers, and turbines could raise machinery output substantially. With a suitable hull and four-shaft arrangement, a Nelson-derived ship might reach roughly 27.5 to 28 knots. Propulsion demand rises unevenly as a hull crosses successive resistance thresholds, so extra horsepower does not translate into speed at a constant rate. A later comparison with the Iowa class shows why boiler count alone is misleading: Nelson used mid-1920s pressure and boiler technology, while Iowa benefited from late-1930s development.