Speed increases require a workable combination of hull shape, displacement, and machinery output. The discussion treats roughly 21-23 knots as an efficient range for existing dreadnought forms. An intermediate 24-25-knot design can leave a hull underpowered or demand excessive power from a form poorly suited to that speed. The next attractive combination is placed around 28-30 knots, with displacement rising into the forty-thousand-ton range. This helps explain the substantial increase in ship size projected in response to Italy.
Notable Point · 1:35:19-1:36:31
Why the next battleship speed step could be 28 knots
Hull form, displacement, and machinery output help explain a jump from 21-23 knots to roughly 28-30 knots.