A seaplane tender worked as a mobile base, not a carrier

A tender might carry aircraft, lift them from the water, maintain them, or provide launch equipment, but routine operations generally required a harbor or bay. HMS Pegasus, formerly HMS Ark Royal, illustrates one of only two such British capabilities supporting Supermarine Walrus patrols. Because Britain had not built a broader tender force, it had little incentive to develop a purpose-built long-range aircraft for it. The contrast between Kingfisher-scale reconnaissance and the Catalina shows the resulting gap. The political geography narrowed the available bases: the Azores were Portuguese, Iceland and Greenland were Danish, while Bermuda, Canada, and Newfoundland lay within the British imperial network. Wartime occupation or alliance arrangements could open more locations, but they did not remove the need for sheltered water. Launching and recovering seaplanes while underway was theoretically possible but risky for both aircraft and crews. Because the ship was better understood as a relocatable base than an underway flight deck, it could not replace escort carriers or long-range land-based aircraft in the central Atlantic.