Early treaty-era utility destroyers could not carry enough guns and torpedoes for every late-1930s threat. Tribal-class ships traded torpedo weight for gun power, which later made a twin 4-inch high-angle replacement easier than on ships that had to surrender an entire torpedo bank. The delayed response is linked to the interwar relationship between the Admiralty and Air Ministry, followed by the late transfer of Fleet Air Arm control. A true general-purpose 4.5-inch upper-deck mount was under development but did not arrive in time for the war and eventually appeared with the Daring class. British destroyer doctrine therefore had to combine 4.7-inch low-to-medium-angle fire, 4-inch high-angle defense, lighter weapons, and torpedoes rather than use the desired single general-purpose system.
Notable Point · 2:32:57-2:38:18
Air attack forced British destroyer armament to change
The Royal Navy needed more high-angle firepower, but institutional delay and an unfinished 4.5-inch mount forced wartime compromises with 4-inch and 4.7-inch weapons.