How war disrupted Royal Navy carrier replacement plans

Furious often ferried aircraft to Malta rather than operating as a fully modern fleet carrier. Larger aircraft and air groups would also have required further upgrades. Ark Royal had been added to the force, while Furious, Hermes, and Eagle were meant to give way to three Illustrious-class carriers. Indomitable and Implacable were intended to replace Courageous and Glorious under the treaty system, with Unicorn providing extra capacity. War interrupted that sequence and left the fleet short of smaller escort carriers that wartime operations soon demanded.