Air Defence of Great Britain (ADGB) astonishing productive capacity of the United States The IJN built 14 carriers during the war (all types), including conversion of a super battleship hull into the massive IJN Shinano The IJN also turned to smaller seaplane carriers, using these not as a strike force but to ferry aircraft into increasingly isolated Pacific outposts The IJN could no longer stock its fleet carriers with naval aircraft by early 1944, while pilot quality and general morale had also badly deteriorated The Japanese were reduced to using their last fleet carriers as planeless lures at Leyte Gulf By the end of the war the Japanese lost all their carriers to enemy action, either sunk or so heavily damaged they were put out of action In contrast, the United States started the war in 1941 with seven fleet carriers Before the fighting ended in August 1945, the U.S Navy commissioned an astonishing 104 carriers (all types) It thereby claimed a naval air power preponderance it has yet to surrender U.S carrier types included prewar fleet and experimental carriers, escort carriers, and three other main classes: Independence-class light carriers, Saipan-class light carriers, and Midway-class fleet carriers U.S and Japanese carriers began the war with wooden fl ight decks, but both navies moved to armored fl ight decks as their earlier designs proved vulnerable to dive bombers Like the IJN and U.S Navy, the Royal Navy experimented with carrier design during the interwar period Most British carriers had armored decks from the start of the war because the British anticipated operating within range of land-based aircraft while intending to use their carriers for a primary reconnaissance role for surface battle groups A key feature of USN fleet carriers was their ability to embark more aircraft than either Japanese or British carriers American carriers also could launch and recover planes more quickly than the Japanese, a trait that provided an important advantage in the great carrier battles of 1942 See various naval battles and operations See also Catapult Aircraft Merchant (CAM); Doolittle raid; Habakkuk; Merchant Aircraft Carrier (MAC); Okinawa AIR DEFENCE OF GREAT BRITAIN (ADGB) The original and unified RAF command in charge of home defense from 1925 to 1936 It was replaced by separate RAF commands from 1936 to 1943: Fighter Command (active air defense) and Bomber Command (deterrence and retaliation) The ADGB was revived and reshaped in 1943 The principal reasons for doing so were the changed nature of the air war with Germany and to accommodate Western Allied fighter and anti-aircraft defenses needed to protect invasion airfields, marshalling areas, embarkation points, and shipping before and during OVERLORD ADGB thereafter carried out antisubmarine recce and patrols and provided air cover over the landing beaches and lodgement areas at the start of the invasion To those ends, the ADGB was subsumed under the Allied Expeditionary Air Force (AEAF) The ADGB deployed 45 squadrons hosting over 800 aircraft on June 5, 1944 Another 12 squadrons were attached from the 2nd Tactical Air Force (TAF), which was also part of the AEAF The 2nd TAF assumed forward operations once the beachhead was secure and inland airstrips became available, except over the Côtentin Peninsula ADGB anti-aircraft guns were active and effective in shooting down V-1 rockets fired against Britain in late 1944 22