During World War II, the United States Air Force, the United States Air Force (USAAF), was not an independent type of armed force and was formally under the command of the Army. Thanks to an excellent production base and efficient organization, they became the most powerful military aircraft in the world during the Second World War. It is also worth remembering that the USAAF has grown enormously in terms of personnel - in 1939 they numbered about 25,000 people, but at their peak, that is, in the summer of 1944 - as many as 2,400,000 people! So in five years they have increased almost 100 times! This number is about 300 thousand. were officers, and about 2.1 million were private and non-commissioned officers, mostly on the ground. Despite this tremendous growth, the USAAF implemented effective training systems and methods that made the majority of the above-mentioned personnel perform their tasks effectively. It can also be noted that all kinds of technical and mechanical means were widely used in ground maintenance work, which reduced the number of hours needed to solve this machine for takeoff and flight. It should be remembered that the number of US foreign air bases also increased dramatically, in December 1941 there were 19 of them, and in May 1945 - as many as 130!