How carrier navies kept spare aircraft available

How did Japanese, German, British, and American carriers provide spare aircraft?

They carried either complete spare aircraft or enough crated assemblies and components to replace losses, with British stocks sometimes supporting field assembly away from factories.

Several carrier navies carried replacement aircraft or substantial stocks of components. American carriers could store complete aircraft overhead in the hangar, while British practice leaned more heavily on crated assemblies and parts. Wartime examples show how Fleet Air Arm aircraft could be assembled or restored away from normal factories. Sea Gladiators on Malta and radar-equipped Swordfish emerged from distributed component stocks. These reserves made spare-aircraft policy part of operational endurance rather than a simple inventory detail.