River-class turbine trials and hull efficiency

Eden and Thornycroft-built Kennet shared a nominal speed of 25½ knots, although only one had turbines. That turbine installation was the only one in its year's orders, and only two more followed the next year. Differences in hull shape could also account for performance that machinery ratings alone did not explain. The relatively straight bows pushed water aside and lacked the clipper or Atlantic forms discussed as alternatives. Refining the bow curves and underwater form offered gains alongside improvements in engine power. The comparison with aircraft development shows why a bigger engine eventually needs to be accompanied by attention to aerodynamic details, including the rivets. Destroyer design faced a similar need to develop hydrodynamics as the demand for speed increased.