Prewar seaplane tenders as carrier-reserve preparation

Japan operated several types of seaplane tender during the 1930s and could have designed more for rapid conversion into full-length light carriers. Other navies also prepared peacetime ships for wartime alteration, including Japanese vessels built for later up-gunning and British ships designed to receive armour quickly. A continuing Chitose-type program might have produced six or seven carriers with roughly thirty aircraft apiece, perhaps forty if conversion had shaped the design from the outset. These ships would have remained inferior to American fleet carriers. They could still have provided a larger, more readily available aviation reserve. Seaplane tenders also supplied a peacetime justification under the Washington Naval Treaty's restrictions: mobile ships could support floatplane and flying-boat patrols around island holdings without permanent fortifications. A navy expecting an industrially unequal war needed convertible capacity in place before hostilities.