The most costly, and difficult to operate of all armed forces is the Airforce...skilled pilots take years to train sufficiently (as Germany and Japans later war years proved) Manufacturer's must constantly be upgrading, and designing aircraft..for what worked in 1940, was outdated and outclassed by 1945. Mechanics, outfitters,airfields must be trained, built, moved, and rebuilt.

Italy designed fantastic planes, and had some very skilled pilots...but the skill, or knowledge on how best to use these is a constant debate...i.e.BoB, Stalingrad re-inforcements, etc, air coverage of fleet movements, Malta

bf109 Emil