Originally these two ships were hulls three and four of the Gandalf class Heavy Cruisers. Postponed on the 1st of January 1940, as other ships would need priority, it was not till the end of 1942 that a new design turning the ships into light aircraft carriers was produced and passed by the Admiralty for the two ships to be completed. Nindalf being furthest advanced was completed in October 1943, the Hithoel in March of 1944. Both ships benefited by being completed late war in that they had the Corsair and Avenger aircraft aboard from the start. Purposed with fleet defence, the ships carried a dozen Avengers used mainly for anti-submarine warfare (ASW) while the 26 Corsairs were used for Combat Air Patrols (CAP) over the fleet. Later in 1944 both ships received half a dozen Corsair nightfighters fitted with radar.
The defensive armament also benefited from being a late war fit. No 20mm weapons were fitted due to the lack of knockdown ability versus the Kamikazes. The 40mm weapon system with guns and radar predictors and later proximity shells gave a much better account of themselves. The four pairs of 4" guns provided the long range and barrage firing abilities.
