Coventry and Curlew received ten single 4-inch guns and two octuple pom-pom mountings. Cairo, Carlisle, and Calcutta illustrate another arrangement, with eight 4-inch guns in four twin mounts and four single pom-poms. These remained protected cruiser hulls, with armor over machinery, magazines, and decks. Electrical upgrades prepared them for radar but occupied space previously available for fuel. The stated endurance after conversion was roughly 3,215 nautical miles at 12 knots, compared with the earlier figure of 5,900 nautical miles at 10 knots. Their heavy AA guns and multiple pom-pom mountings gave convoy escorts firepower against several attacking aircraft.
Notable Point · 49:17-52:57
C-class conversions traded endurance for stronger air defense
Different 4-inch and pom-pom arrangements gave older cruisers useful convoy air defense, while electrical upgrades reduced fuel capacity.