Joe Baugher’s website was also archived:
https://web.archive.org/web/20250411231124/http://www.joebaugher.com/
bttt
EXCERPTS:
On August 1, 1907, the Aeronautical Division of the United States Army Signal Corps was established, and the United States Army purchased its first heavier-than-air aircraft, a Wright Model A, in 1908. It was allocated the serial number 1. Further Army aircraft were assigned serial numbers in sequence of their purchase. Unfortunately, early records from these days are rather incomplete, and there are numerous gaps and conflicts.
To add to the confusion, it often happened that at the time an aircraft was rebuilt, it was assigned a brand new serial number. Some aircraft from this period (for example the DH-4 "Liberty Plane") are known to have carried at least four serial numbers during their careers. After a while, certain serial number blocks were introduced--the 200 block was reserved for seaplanes, the 40000 block for experimental aircraft, and the 94000 block for prototypes and aircraft under evaluation.
On July 2, 1926, the Army Air Service was renamed the United States Army Air Corps (USAAC). On June 20, 1941, the USAAC was renamed the United States Army Air Force (USAAF). On September 18, 1947, the United States Army Air Force was split off from the US Army and became a separate service, the United States Air Force. Throughout all of these changes the earlier fiscal-year serial number system remained unchanged.