The British escort force had seven tiers: corvettes, frigates, sloops, Hunt escort destroyers, and small, medium, and large fleet destroyers. The Weapon class occupied the medium tier and the Battle class the large tier, while the C groups served as standard fleet destroyers. Below the Hunts sat Black Swan sloops, frigates, and Flower- and Castle-class corvettes built with progressively more commercial-style methods. Simultaneous construction across these types let the Admiralty use yards with different skills and capacities. Opening the video here gives a compact explanation of the link between naval force structure and industrial mobilization.
Notable Point · 3:23-4:52
The Royal Navy's seven-layer escort ladder
British wartime construction ranged from corvettes and frigates through sloops and Hunts to three scales of fleet destroyer, matching different roles to different shipyard capabilities.