ARNOLD AIR FORCE BASE, Tenn. -- As of Jan. 20, Dr. Bill Baker transitioned from his job as AEDC Technology, Analysis and Evaluation Branch chief to the Technical Director of the AEDC Test Operations Division at Arnold Air Force Base.
Working at Arnold for a span of almost 55 years, Baker has served in numerous roles and has made a significant impact in AEDC research and development. He was awarded the title of AEDC Fellow in 2004 for his innovations in integrating wind tunnel testing, computer modeling, and analysis which identified AEDC as a Center of Excellence in weapon separation simulations. His innovations have been successfully applied to DOD aircraft and weapon systems, with the results of his efforts made evident in Operations Desert Storm, Anaconda and Iraqi Freedom.
His focus has been on the development of analysis capabilities in support of weapons separation and engine inlet integration. Baker developed the technique for predicting store separation trajectories based on regression analysis of aircraft and store experimental data. This represented the first computational technique developed at Arnold for prediction of stores separation.
Baker also developed a high angle-of-attack aerodynamic coefficient prediction technique for missiles that has been used by both U.S. and foreign missile developers. Applications of his prediction tool by the system development teams have included the AIM-120C, AIM-9X, Advanced Concept Technology Demonstration and other similar air-to-air missiles in the U.S. military's weapons inventory.
An engineer from the start
Baker knew he wanted to be an engineer from a young age, building rockets and making rocket fuel in his parents’ basement at age 15.
With guidance from his father, he mapped out high school classes that would prepare him to eventually enroll in the aerospace engineering program at Mississippi State University.
Before heading to college, Baker first joined the Army Reserve in Vicksburg, Mississippi. In January 1959, after six months of active duty, he registered at Mississippi State. It’s here that he would learn about AEDC, at that time known as Arnold Engineering Development Center.
“At the first meeting of the Institute of Aeronautical Sciences, Professor Leslie Hester, the faculty advisor, said that they had planned a visit to the Arnold Engineering Development Center in Tennessee and anyone who wanted to go was to sign up for the trip,” he said.
Baker went on that trip and a couple of others to Arnold as a college student.
Upon graduating from Mississippi State in 1963 with a master’s in Aerospace Engineering, he received an offer from Tommy Warren in the contracting office to work for AEDC with ARO, Inc., but he’d already accepted a job offer from North American Aviation, Inc., in Los Angeles.
“Warren said, ‘Bill, when you get California out of your system, give me a call and come on home,’” Baker recalled.
In July of 1964, Baker was laid off from his job, so he called Warren.
“On Aug. 13, 1964, I drove in the front gate of AEDC as an employee of ARO,” Baker said.
His AEDC career and accomplishments
Baker’s first job was in the Propulsion Wind Tunnel Facility, or PWT, and his first test as a project engineer was one conducted in the 16-foot supersonic wind tunnel, 16S.
“The object was to measure the transition Reynolds Number of the tunnel and to measure the boundary layer on the walls of the tunnel,” he said. “The method of measuring the transition Reynolds Number was to measure the jump in pitot pressure as a probe was moved along the length of the surface of a hollow cylinder at flow Mach numbers of 2.0, 2.5 and 3.0.”
Baker has been part of several memorable aerospace projects in aerodynamics, space and hypersonics that he considers key to his professional growth, such as arc heater testing for re-entry nose cone materials and the leading edges of hypersonic vehicles.
"There was a need to develop diagnostic instrumentation for the measurement of flow properties in these high-temperature flows,” he said. “To fill this need, Harry Kaupp and I developed the Research Arc Heater to better understand the performance of arc heaters and to develop high-temperature diagnostics for pressure, temperature and enthalpy in the arc heated flow.”
A highlight in Baker’s career during the late 1960s and early 1970s was his work for the Bomber Defense Missile.
"This program considered carrying missiles in the bomb bay and performing a maneuver where they pivoted around in mid-air and flew to the rear of the bomber to defeat aircraft attacking from the rear," he said. "To perform this maneuver, the missile would have to turn around in the air exposing the missile to angles of attack from zero to 180 degrees (i.e. flying backwards). There was not a missile aerodynamic coefficient prediction technique available to make these computations. For my Ph.D. dissertation, I developed the High Angle-of-Attack Missile Aerodynamics Prediction Code."
Data was needed to develop the prediction code, so Baker planned the testing, guided the design of the models, worked as a project engineer for the test and built the transonic and supersonic database for missile-specific parameters.
With help from fellow analysis team members, other projects Baker worked on included store separation testing and analysis for the Air Force Seek Eagle Program Office and the F-22 program.
Another assignment that stands out to Baker was one supporting a test technique at Range G, a Hypervelocity Ballistic Range, at Arnold.
“We planned a test where a model was launched at 90 degrees angle of attack in Range G at subsonic Mach numbers so that shadowgraph photographs could be taken of a model without a support sting or strut,” he said.
Baker mentioned the chance to “think outside the box” is part of why he has enjoyed his long career at Arnold.
“It’s great to have that opportunity to improve test techniques and also the opportunity to run facilities at conditions at which you wouldn’t normally run them,” he said.
Baker was employed by five contractors at Arnold before retiring with Aerospace Testing Alliance in 2004. Even as a retiree, he continued to work with ATA on a part-time basis until 2010 when he accepted a position with the Air Force to assist in forming the Analysis and Evaluation Branch at Arnold.
If he’s not working, one can likely find Baker spending time with his wife Nancy or practicing the tuba or bagpipes. Baker spent 25 years as a member of the Tennessee Valley Winds Band based in Murfreesboro and about 5 years in the Nashville Pipes and Drums.
Though Baker would have loved to have been a professional musician, he says that engineering is one hobby he’s been able to do full-time.
“Work is my hobby,” he said. “I’m still excited to come to work every day. The work that we are doing here at Arnold is so important. It helps to have a purpose for your mission, and we definitely have that at AEDC.”