Despite the fact the Army aviation branch celebrates it's official inception on 12 APR 1983 and therefore appears to be the youngest service in terms of aviation, it's not. Army aviation is actually the oldest, it began with use of balloons during the Civil War. After the Wright Brothers first flight in 1903 who was the first to purchase a heavier-than-air flying machine from them? The U.S. Army Signal Corps, who purchased the first Wright Military Flyer on the 30th of July, 1909 for $25,000 -- and thus American military aviation began.