Originally, before the Air Force became its own branch, the United States Army possessed a rapidly changing aviation division going under the various names of the Aeronautical Division from 1907 to 1914, the Aviation Division from 1914 to 1918, the Air Service from 18-26, the Army Air Corps from 26-41, and the Army Air Forces from 1941-1947.

The reason for this constant change was largely due to technological advancements and the recognized value of air power. By 1913, the state of aeronautical advance in the United States was largely represented by the accomplishments of Glenn Curtiss. However, European leaders were investing heavily into air power, and held large competitions which steadily increased the technological advancement of airplanes as we made them faster, stronger, able to fly longer, and etc.

Europeans incorporated aircraft units into their armies, while in the United States, at first, we had six pilots.

As in most wars, technological advancements in weapons and support were greatly increased - however the United States still did not match up the the Europeans. The NACA (National Advisory for Aeronautics, which later was transformed to NASA) made great efforts to put us on-par with the Europeans over the years.

The formation of the United States Military at the time would work so that the Army focused on ground-based- combat, the Navy and Marine Corps focused on naval and ground combat... And so as the value of air superiority became more important, the United States Air Forces became more and more independent and complex.

Because of these reasons, with the implementation of the National Security Act of 1947, the United States Army Air Corps took its place as the United States Air Force, its own individual branch.