How British carrier studies turned missions into compromises

British constructors began by defining the carrier's missions and sketching an ideal ship of roughly 27,000 tons. They then compared that ideal with the tonnage the navy was willing or permitted to allocate and removed capabilities until the design fitted. Cumulative treaty allowances therefore affected which parts of an otherwise desirable design survived into an order. Different priorities produced the 1931 studies' generous lifts and flagship accommodation, Ark Royal's emphasis on aircraft numbers and the Illustrious class's emphasis on survivability. The design papers preserve the reasoning behind compromises that are harder to explain by comparing completed ships alone.