ARNOLD AIR FORCE BASE, Tenn. -- When the Air Force needed someone to lead the new Arnold Engineering Development Center through its earliest of days, it looked no further than one of the men who played an instrumental role in its establishment.
Maj. Gen. Franklin O. Carroll served as the first commander of AEDC.
Carroll was born in Washington, Ind., in 1893. He earned his Bachelor of Science in electrical engineering from the University of Illinois in June 1916, the same month he began his military career with the Illinois National Guard Horse Cavalry. He served on active duty with the calvary until that November, performing border patrol in Brownsville, Texas. Carroll also served with Gen. John Pershing’s Expeditionary Force that searched for Poncho Villa.
In May 1917, Carroll entered Officers Training Camp at Fort Sheridan, Ill. That August, he began flight training at Kelly Field, Texas. He was commissioned as a first lieutenant in January 1918 in the Aviation Section of the Signal Reserve and was assigned to Kelly Field as an instructor, teaching students to fly planes as World War I continued.
Carroll was assigned to the Office of the Chief of Air Services in Washington, D.C., in June 1919. In September of the following year, he entered the Massachusetts Institute of Technology and completed the Air Service Course in June 1921.
Carroll was the first Air Service Officer to be trained in aeronautical engineering.
Following assignments that included time in Ohio at McCook, Kelly and Wright Fields and his graduation from the Air Corps Tactical School at Maxwell Field, Alabama, Carroll was again assigned to Wright Field in 1939 as chief of the experimental engineering section’s research and development branch.
The following year, Carroll served a three-month stint as an assistant military attaché in London, England. Afterward, Carroll returned to Wright Field as chief of the experimental engineering section, serving in that capacity until the end of World War II.
“During his tenure, he was at the center of every major experimental and engineering project at the field during World War II,” Carroll’s biography on the Air Force website states. “He approved the creation of the world’s most advanced wind tunnels and laboratories for aeromedical research, communications, navigation and radar. He also oversaw the introduction of the first jet engine to Wright Field. In short, he made the tough engineering decisions that translated proposals and requirements into airplanes – some of the best airplanes in the world.”
Carroll was promoted to brigadier general in October 1942.
Additional assignments followed and, in January 1947, Carroll was assigned to the Air Materiel Command headquarters at Wright Field as assistant to the deputy commanding general for engineering. That June, he was transferred to the Office of Assistant Chief of Air Staff for Materiel at Air Force Headquarters in Washington, D.C. He also served as Army Air Corps representative on the National Inventors Council.
In August 1947, Carroll moved to the Office of Assistant Chief of Air Staff for Materiel as deputy chief of the Research and Engineering Division. That October, he was promoted to the rank of major general and became director of research and development at Air Materiel Command.
Carroll in October 1949 became assistant deputy chief of staff for materiel at the Air Force Headquarters in Washington, D.C. Later that same year, Carroll was named the first commanding general of the Air Engineering Development Division.
The AEDD was established at Wright-Patterson Air Force Base, Ohio, on Jan. 1, 1950. The purpose of the AEDD was to oversee the creation of the Arnold Engineering Development Center near Tullahoma, Tennessee.
Less than two years prior, the middle Tennessee-based Camp Forrest, one of the Army’s largest training bases during World War II and an active Army post between 1941 and 1946, was named as the site for the Air Force’s new center.
Carroll’s role in helping make AEDC a reality began prior to the decommissioning of Camp Forrest.
As commander of the engineering division at Wright Field, Carroll recognized that the testing of jet engines at Wright Field would require more space and power than was available there without reshaping existing facilities. Carroll’s concern was shared by scientist Frank Wattendorf, who reported the same consternation while acting as a research adviser to the general.
However, in November 1944, Gen. Henry “Hap” Arnold, the commanding general of the U.S. Army Air Forces during World War II, directed the formation of the Scientific Advisory Group. This group was responsible for providing recommendations on the future direction of U.S. aviation research.
In May 1945, the Scientific Advisory Group visited Germany to survey testing and research facilities there. What they found was that the Germans had facilities more advanced that the Allied nations had imagined.
Wattendorf was among those who made the trip to Germany. Wattendorf documented his findings, and his report, known as the Trans-Atlantic Memo, was the first recommendation for a site such as AEDC.
“The scope of the German plans makes it essential that our own plans be certainly not less ambitious in the light of our future security,” Wattendorf’s memo stated in part. “It is recommended that consideration and study be given the establishment of a new Air Forces research and development center.”
Wattendorf’s June 19, 1945, memo was delivered to Carroll and became the basis of a presentation Carroll gave to Gen. Arnold’s Air Staff.
“In his presentation, Carroll advised the Air Staff of the advancements in ground testing that the Germans had made and outlined the deficiencies in America’s wind tunnels,” Beyond the Speed of Sound, a book detailing the history of AEDC, states. “He noted that ‘no facilities exist [in the U.S.] for the testing of turbojet compressors.’ Carroll also listed what he felt were the necessary facilities for U.S. research and development, suggesting that the Air Technical Service Command be charged with making a preliminary study ‘for the establishment of a new Army Air Force’s Applied Research and Development Center for Fluid Dynamics.”
In July 1945, Maj. Gen. E.M. Powers, assistant chief of staff, materiel and services, instructed Carroll to proceed with his suggestion. That October, Col. Paul H. Kemmer, Carroll’s deputy, formed a committee to complete the recommended study. Around the same time, the Scientific Advisory Group was completing its own report, titled Toward New Horizons. Both the Kemmer Committee report and Toward New Horizons were published in December 1945, and both called for the using captured German test facilities in a new installation to be to be located near large sources of water and electrical power.
Congress eventually appropriated funding for the construction of the center and, in March 1950, the Secretary of Defense approved its construction.
This is the seventh in a series of articles highlighting the history of Arnold Engineering Development Complex during its first 75 years. Additional articles will be published throughout 2026 to commemorate the anniversary of AEDC.