The Type IV reverted to 40 depth charges, two throwers, and one rack, the original Type I level, rather than the 110-charge outfit of Types II and III. An escort destroyer needed capacity against submarines and aircraft more than a marginal torpedo capability against larger surface ships. Before modern towed arrays, helicopters, sonobuoys, and similar systems, navies needed more ships on the water to maintain contact and coverage. In that context, mass and sustained escort capability mattered more than trying to imitate a fleet destroyer.
Notable Point · 54:22-1:00:03
The Type IV trade-off: torpedoes for escort endurance
Type IV's greater torpedo armament came with a return to the Type I depth-charge outfit, weakening the anti-submarine focus that made Hunts valuable escorts.