The hull and plating look mercantile, but the screw blades do not. Their form resembles the more demanding propellers expected on a liner or another relatively fast merchant ship. The blade shape supports low-speed manoeuvring as well as efficient straight-line dashes. That flexibility mattered to an escort that had to work around convoys and then accelerate toward a contact. The detail captures the River-class formula: naval performance inserted into a hull built by methods closer to merchant practice.
Notable Point · 13:17-16:32
Naval performance hidden beneath a merchant-style hull
Diamantina's propeller blades illustrate how the River class combined merchant-compatible construction with naval requirements for maneuvering and high-speed dashes.