Japan's Shinano had the thickest hangar decks (7.5 in) among some of the World War II era aircraft carriers.
Shinano (64,800 tons) 7.5 in (190 mm) Armour thickness of some World War II era aircraft carriers 2 in (51 mm) 1.52.5 in (3864 mm) 2.5 in (64 mm)       Hiryu (17,800 tons) Ark Royal class (22,000 tons) Shokaku class (25,600 tons) Taiho (29,770 tons) Implacable class (23,500 tons) [[United_States]] Midway class (45,000 tons) 
