Some navies understate performance by testing fully laden ships, while others chase impressive figures with lighter loads or forced draft. The useful measurement is how efficiently the machinery moves a known displacement under known conditions, rather than the headline speed alone. Trial-area currents and crosswinds can materially change the result, so apparently comparable figures may rest on very different tests.
Notable Point · 27:38-35:38
Speed trials depend on load, machinery, wind, and current
Published top speeds can reflect deliberately chosen loads and trial conditions, while the deeper engineering purpose is to measure propulsion efficiency and range.