The reported difference is striking: one Type IV could make 950 nautical miles at 25 knots and the other 1,175 nautical miles. The ships were laid down a day apart at the same Thornycroft yard and had the same stated speeds, making the range divergence difficult to explain from the available design information. Their original quad Vickers .5-inch machine-gun fit and continued reliance on too few torpedoes also look questionable. The available information does not support a technical explanation for the range gap.
Notable Point · 1:00:03-1:05:28
The unexplained range gap between Brecon and Brissenden
Despite being a two-ship subclass from the same builder, Brecon and Brissenden reportedly differed by 225 nautical miles of range at 25 knots.