Treaty limits had forced navies to trade air-group size against protection, and their removal gave British and American designers more freedom. The US Navy expected to operate across the wider Pacific, where sea room and air strength offered ways to avoid or disrupt attacks. British plans also required operations in the Mediterranean, the South China Sea and close to Japan, where limited manoeuvring room made protection more valuable. The Royal Navy's experience of North Sea conditions also complicated enthusiasm for a fully open hangar. A ventilated hangar needed enough airflow to warm engines without exposing the entire aircraft space as an open gallery.
Notable Point · 56:01-57:47
Why operating areas shaped carrier armour and hangars
Pacific sea room, confined British operating areas and North Sea weather produced different compromises between aircraft capacity, protection and hangar ventilation.