Arnold AFB, Tennessee
The mission of Arnold AFB is to support the development of aerospace systems by testing hardware in facilities that simulate flight conditions. Arnold Engineering Design Center (AEDC) also conducts a research and technology program to develop advanced test techniques and instrumentation and to support the design of new test facilities. AEDC has contributed to the development of nearly every national aerospace program since the 1950s.
The center operates 53 aerodynamic and propulsion wind tunnels, rocket motor and turbine engine test cells, space environmental chambers, arc heaters, ballistic ranges and other specialized units. More than 13 of the center's units have capabilities unmatched anywhere else in the world. The test facilities can simulate flight conditions from sea level to level to space and from subsonic speeds to well over mach 20.
Arnold Engineering Development Center is the world's largest and most complex collection of flight simulation test facilities. The 4,000 acres that comprise AEDC are part of the 40,000 acres of Arnold Air Force Base. Dedicated June 25, 1951, by President Harry Truman, AEDC has tested virtually every high performance aero-space system the Department of Defense has used since.
AEDC supports the development of aerospace systems through its major testing facilities broken into three business areas: aerodynamics, aeropropulsion and space and missiles.
The majority of the aerodynamic testing is done in the two large wind tunnels in the Propulsion Wind Tunnel facility. The facility has two 16-foot wind tun-nels, one supersonic and one transonic. Transonic refers to speeds just below and just above the speed of sound. The tunnels are used primarily to test the aerodynamic performance of large models of aircraft, spacecraft, rockets or full-scale smaller sized missiles like the Navy Tomahawk missile. During wind tunnel tests, conditioned air is blown past a stationary model and flight characteristics are measured. In some cases, the propulsion sys-tems and inlets are tested simultaneously to make sure they are designed to provide adequate airflow to the engine under all flight conditions.
A four-foot transonic wind tunnel is used for compatibility and separation testing. Store separation investigations make sure bombs, missiles, fuel tanks or other externally-carried stores separate cleanly from the aircraft when released. Three hypersonic wind tunnels in the von Karman Gas Dynamics Facility also are operated under the Aerodynamics business area Test and evaluation tools include not only wind tunnels, but also computational modeling, including Computational Fluid Dynamics.
Flight testing is risky and costly. To mitigate these risks, AEDC is increasing the use of Integrated Test and Evaluation. An integrated, knowledge-based approach to development, test and evaluation reduces cost by increasing computer modeling and wind tunnel simulation accuracy and fidelity, reducing the number and duration of individual flight tests required and reducing flight test costs.
The Engine Test Facility's engine test cells are used for the development and evaluation testing of propulsion systems for high performance aircraft. Ground testing of these air-breathing engines provides test data evaluating the performance, operability and reliability of the engine. It can help cut development time and the number of test flights required for a manned aircraft or unmanned weapon system.
ETF's Aeropropulsion Systems Test Facility with two test cells provides engine testing from takeoff, through climb to altitude and multi-speed combat maneuvers, to descent and landing. ASTF is designed for full-mission simulation of advanced jet engines. ASTF has tested large commercial jet engines like Pratt & Whitney's 4000 series and Rolls-Royce's Trent 800, both used on the Boeing 777. High performance military jet engines like the Pratt & Whitney F119 for the new Air Force F-22 Raptor and the multi-service, multi-national Joint Strike Fighter are under development in these test cells.
The Space & Missiles Systems Division operates hypersonic wind tunnels, rocket test cells, space environmental chambers, arc heaters, ballistic ranges and other specialized test units. These test facilities can simulate flight conditions from sea level to altitudes of 300 miles and velocities from subsonic to well above Mach 20.
Large Rocket Test Cell J-4 is the largest simulated altitude liquid rocket engine test cell in the world. It tests liquid fueled rocket engines under near space conditions. The upper stage motor for the Apollo moon program's Saturn V launch vehicle was tested here as well as upper stage engines for Titan and the Air Force's new family of heavy lift Evolved Expendable Launch Vehicles.
Large Rocket Test Cell J-6 is the largest simulated altitude solid rocket motor test facility in the world, capable of firing solid rocket motors of up to 500,000 pounds thrust at simulated altitudes of 100,000 feet. Minuteman and Peacekeeper Intercontinental Ballistic Missile upper stage motors are test fired in this test cell.
Rocket propulsion systems are tested to measure thrust, propellant burning, nozzle control, shutdown characteristics and ignition.
Camp Forrest, located in Tullahoma, Tenn., was constructed as one of the Army's largest training bases during the World War II period between 1941 and 1946. The camp, named after Civil War cavalryman General Nathan Bedford Forrest, was originally named Camp Peay. Camp Peay was named after 1920's Tennessee Governor Austin Peay and built east of Tullahoma, Tenn. as a National Guard Camp in 1926. Camp Peay covered 1,040 acres. Camp Forrest covered 85,000 acres located just beyond the old Camp Peay.
The camp was a training area for infantry, artillery, engineer, and signal organizations. It also served as a hospital center and temporary encampment area for troops during maneuvers. Maj. Gen. George S. Patton brought his 2nd Armored Division, "Hell on Wheels," from Fort Benning, Georgia for maneuvers. Incoming troops were provided with amenities such as service clubs, guest houses, library, post exchanges, post office, hospital, religious services, theaters, showers, Red Cross, and Army emergency relief. Recreation facilities included swimming, archery, tennis, a sports arena and a 9-hole golf course.
Northern Field, an air training base, was an addition for war preparation. The field was used as a training site for crews of multi-engined B-24 bombers of the Army Air Force.
Camp Forrest officially became a Prisoner of War Camp on May 12, 1942. The camp received, housed, secured, and administrated Italian, Japanese and German POWs. Prisoners were processed as laborers at Camp Forrest, the hospitals and in the local community on farms. In 1945 the U.S. government implemented an Intellectual Diversion Program which would enlighten Germany on American way of life and increase their appreciation for the USA. This program used educational and recreational media to change views of POW's. The program was successful with many prisoners.
Tullahoma was greatly affected by the installation of Camp Forrest. Because of maneuvers and operations, civilians became accustomed to blocked roads, traffic jams, crowded stores, the absence of mail delivery, and driving at night without lights. Soldiers camped out on lawns and fields. Many crops and fences were destroyed. In 1940 the population in Tullahoma was 4,500. By the end of the war the population had grown to 75,000. Many military people who moved in for construction and operation of the camp remained after the war.
After the war, 1946, Camp Forrest and Northern Field were declared surplus property. Buildings were sold at auction, torn down and carted away. Water and ssewage systems and electrical systems were sold as salvage. All that remains are roads, brick chimneys and concrete foundations. Soon after the close of the camp, the area was selected for the site of an Air Engineering Development Center.
In 1949, Congress authorized $100 million for the construction of the Air Engineering Development Center. A site was selected for the new center at the Army's old Camp Forrest near Tullahoma and Manchester, Tenn. The site was chosen for its abundance of land, water and power. Land was needed to buffer surrounding communities from potential test hazards and noise. Water was needed to cool rapidly flowing air and hot exhaust gases. Abundant electricity was needed to power huge testing systems. Construction on the center started in 1950. On June 25, 1951, a year after General Arnold's death, President Harry S Truman dedicated the Air Engineering Development Center in Arnold's honor, naming it the Arnold En-gineering Development Center.
One of the government's early decisions concerning the center was to employ a primarily contractor work force. The Arnold Research Organization known as ARO was formed by Sverdrup and Parcel to become that contractor work force. Part of the rational was to maintain a stable work force that came to accumulate a volume of experience with the test facilities that were to be built. That idea would make the center a model for outsourcing for the Department of Defense by the 1990s. The 1950s saw the development of three major test facilities that remain active today - the Engine Test Facility, the von Karman Gas Dynamics Facility and the Propulsion Wind Tunnel Test Facility.
The first jet engine test equipment installed at the center was acquired from the Bavarian Motor Works in Munich, Germany. It took 58 railroad cars and two barges with another 450 tons by truck to move the equipment. After refurbishment, this equipment became the cornerstone for the Engine Test Facility, which was completed in 1953. By May 1954, the facility was put to work, testing the General Electric J49 engine for the B-47 bomber.
A flight dynamics facility for testing aerospace designs at high speeds was built and dedicated to Dr. Theodore von Karman in 1959. Operations began with a prototype test cell called E-1, which was used to test the Falcon guided missile. Construction was completed on the Propulsion Wind Tunnel Test Facility at the end of the decade. PWT's huge wind tunnels have become hallmarks of the center and are perhaps the most heavily used facilities on base.
As the space race heated up, so did AEDC's workload. PWT was used to investigate onfigurations for the Mercury space capsule, which sent Alan Shepherd and John Glenn into space. The center was a key player in supporting Project Gemini, and the center played a multi-faceted role in supporting the Apollo Program, which put man on the moon. Apollo tests included aerodynamic assessments of the Apollo capsule and tests of Saturn 5 rocket upper stage engines.
Some new test facilities came on line to help turn numerous aerospace system ideas into reality. The J-4 Large Rocket Engine Test Facility was dedicated in 1964. PWT got an addition in 1968 when the 4-foot Transonic Tunnel came on line, which is used largely to test store separations.
With several test facilities running at full bore, the pace of testing increased exponentially. Among the systems tested during the decade were the F-105 Thunderchief, C-141 Starlifter and C-5 Galaxy cargo planes, the E-3 Sentry, Airborne Warning and Control System (AWACS), the TF39 engine for the C-5 and the upper stage rocket motors for the Minuteman III Intercontinental Ballistic Missile. In the middle of the decade, the University of Tennessee and AEDC worked together in founding the University of Tennessee Space Institute. The institute became a place for AEDC engineers and scientists to further their education, and for students and professors to work on research projects to help AEDC.
There came a natural turndown in the furious pace of aerospace after the moon landing and the end of the Vietnam War. But despite the turndown and a corresponding reduction by the government in funding for AEDC and the number of its employees, the pace of testing held steady as nearly 3,000 test projects were completed in the decade.
The list of systems tested during the decade read like a who's who of aerospace. Included on that list were the Space Transportation System, which would later be called the Space Shuttle, the F-15 Eagle, F-16 Fighting Falcon, B-1 Lancer bomber, A-10 Thunderbolt II, Pratt & Whitney F100 engine, MX missile, Sidewinder missile, Navy Tomahawk Cruise Missile, Air Force Air-Launched Cruise Missile and the Global Positioning Satellite.
AEDC developed Laser-Illuminated Photography during the decade to better study projectiles in the center's ballistic ranges that would be traveling up to 20,000 mph. The technique provided a photographic exposure equivalent to 20 billionths of a second.
A heritage for environmental stewardship and uniqueness was born in 1976 when the Department of Interior registered AEDC as a unique natural area. The honor recognized AEDC's superior management of fish and wildlife resources, conservation practices and environmental achievement.
And in a decade when the nation turned energy conscious, AEDC help explore alternative energy sources. A 750-ton magnet was used as part of a magnetohydro-dynamics research demonstration at the center, sponsored by the Department of Energy. The demonstration assessed the effectiveness of using a large MHD generator to boost coal's efficiency in producing electricity. AEDC later transferred the project to the University of Tennessee Space Institute.
The conflict in the Persian Gulf at the beginning of the 1990's became a defining event in late 20 th Century America. It also showed the world what AEDC had been doing in the 1980s. As people around the world watched from their living rooms, people saw the United States score overwhelming victories in Desert Storm. And they saw the end product of what AEDC people had been working on throughout the decade. From the Patriot Air Defense Missile to the F-117A Nighthawk stealth fighter, AEDC people worked on every aerospace system deployed to the Persian Gulf. It was the first time technology showed up so dramatically in a real-world conflict, and it was a testament to the test and development work Arnold, von Karman and Wattendorf envisioned would be performed at AEDC.
The 1980s also marked the addition of the world's largest jet engine testing facility - the Aeropropulsion Systems Test Facility - to the center's collection of aerospace flight simulation test facilities.
And for the first time in the center's history, more than one major contractor performed work on base. The center's workload split into three contracts - support, propulsion testing and aerodynamics testing. In 1981, Pam Am World Services became the support contractor, Sverdrup Technology Inc. took over propulsion testing and Calspan Corp. began aerodynamics testing. In 1985, Schneider Services International replaced Pan Am as support contractor.
The 1990s were a decade of change at AEDC. From opening its doors to commercial customers to "reengineering," the center's people explored better ways of doing business. Early in the decade, the center signed formal, long-term working alliances with a number of commercial aerospace organizations (Boeing, General Electric, Lockheed, McDonnell Douglas, Pratt & Whitney) in hopes of steadying workload and to offset dwindling defense budgets. That led to companies like Pratt & Whitney and Boeing bringing projects that were strictly commercial to AEDC.
AEDC leaders began to emphasize strategic management, meeting in focus groups to consider the long-term health of the center and to formulate ways to make the future brighter. An outgrowth was reengineering the center, an ongoing process that seeks to streamline operations and standardize maintenance processes. It was also a decade that saw the center break new ground on the computational front. Computational Fluid Dynamics, using computers to simulate flight, saw an ever-increasing role in the scope of many major test programs. Using CFD and traditional ground testing together, helped hold down costs and provide more reliable data to test customers. In 1998, the center was designated as one of the Department of Defense's High-Performance Computing Centers, making funding available to augment the center's supercomputing capability making AEDC the 9th largest computer center in DoD.
The Navy docked at AEDC when its engine test facilities at Trenton, N.J., were transferred to AEDC as part of DoD consolidations under the Base Realignment and Closure Act. The move added four engine test facilities (SL-2, SL-3, T-11, T-12) and about 10 Navy people. The Air Force and Navy quickly integrated, making the center's vice commander and other slots Navy positions. Later in the decade, on Oct. 1, 1997, AEDC assumed management for the former Navy Hypervelocity Wind Tunnel 9 in White Oak, Md.
Other facilities that came on line during the decade included J-6 - the world's largest solid rocket motor test facility - and DECADE, a nuclear weapons effects facility. Among facilities that saw significant modernization were the J-4 Liquid Rocket Engine Test Facility, the Aeropropulsion Test Unit and the Engine Test Facility. PWT also saw a major sustainment and modernization program begin. A number of major aerospace programs came to AEDC for testing, including the F-22 Raptor, the Joint Strike Fighter, the F/A-18E/F Super Hornet, the B-2 Spirit stealth bomber, the Pratt & Whitney 4000 series engines for the Boeing 777 and F119 engines for the F-22 and Joint Strike Fighter, the Boeing 747 and 767 and the RL-10 rocket engine.
The center's workload consolidated to two divisions - test and support - in the mid 1990s, with Sverdrup as test support contractor and ACS as center support contractor. ACS is a joint venture of Computer Sciences Corp., DynCorp and General Physics.
In Sept 2002 a $10.4 million test facility upgrade was announced, and when completed the upgrade would make Arnold Engineering Development Center a "one-stop" shopping center for aerodynamic and propulsion test customers by providing Mach 8 capability. The Mach 8 milestone, which equates to objects traveling about 6,000 mph, comes as workers install a new high-temperature and high-pressure burner in the center's aerodynamic and propulsion test unit. This nearly doubles the center's current test capabilities of Mach 4.1 or nearly 3,100 mph. AEDC test experts can run at Mach 8 for three to six minutes which allows them to test an object across the full-duration mission profile. The project also calls for adding an improved air ejector system to allow the APTU to simulate higher altitude conditions while minimizing air usage. Installing the high-pressure air storage tanks and new liquid oxygen and isobutane systems are also included in the upgrade. Spring 2004 is the targeted completion date.