Daring's 30-knot rating included war loads and months out of dock

The postwar British design documents described here rate speed under demanding service conditions: full wartime loading, six months out of dry dock and tropical temperatures. A battleship expected to maintain 30 knots in those circumstances could need the power to reach roughly 35 knots when new and more lightly loaded. The Daring-class destroyers supply a practical comparison because their stated 30 knots was presented as a speed they could guarantee under those adverse conditions. Better conditions allowed higher speeds without making the service rating misleading. An anecdote claims that a freshly prepared Daring reached 43 knots when its captain wanted to demonstrate the ship to his father. That figure came from a diary entry which the historian explicitly says he could not verify, so it remains an unconfirmed example.