Alexander H. Flax

After the war ended, Flax was offered a position as assistant head of the Aeromechanics Department at the Cornell Aeronautical Laboratory in Buffalo, New York.[8] Here, he continued his work on helicopters, particularly the study of blade dynamics and stability. Along with his associate Harold Hirsch, he developed and tested a fiberglass composite material rotor blade. He also became involved in the development of supersonic ramjet propulsion in collaboration with the Applied Physics Laboratory at Johns Hopkins University.[6][9] He developed the perforated-wall wind tunnel for testing transonic flows, making use of electronic gauges to study this phenomenon. He was also one of the inventors of the wave superheater, which can generate airflows at temperatures hitherto attained only in rocket exhausts.[6][10]

Flax became head of the Aeromechanics Department in 1949, and Assistant Director of the Cornell Aeronautical Laboratory in 1955. He also served as its Vice President and Technical Director from 1961 to 1963.[8] As such, he exercised managerial and technical guidance over all the work of the laboratory. Not all of this was related to aeronautics; projects included research into neural networks; the design of automobile safety features such as seat belts and crumple zones; pioneering work; and development of weather radar.[11] In 1951, he married Ida Leane,[8] who had served as an Army cryptanalyst during World War II, and worked at Piasecki as a mathematician. They had one child, a daughter called Laurel.[12]

In addition, Flax served on various boards and commissions, including the National Commission on Aerodynamics from 1952 to 1954, its subcommittee on high-speed aerodynamics from 1954 to 1958, and the National Aeronautics and Space Administration (NASA) Advisory Commission on aircraft aerodynamics from 1958 to 1962,[13] and earned a PhD in physics from the University of Buffalo in 1958, writing his thesis on "Approximate methods for the calculation of the scattering of particles by atoms and nuclei".[14]

Flax served as the Chief Scientist of the U.S. Air Force (USAF) from 1959 to 1961, and the Assistant Secretary of the Air Force for Research and Development from 1963 to 1969.[8] As assistant secretary, he promoted advanced aircraft engine development through the Lightweight Engine Gas Generator Program and Advanced Turbine Engine Gas Generator Program, which developed engines that eventually went into the McDonnell Douglas F-15 Eagle and the General Dynamics F-16 Fighting Falcon fighter aircraft, and a new generation of high-bypass engines for large, long-range transport aircraft. Based on his experience with fiberglass helicopter blades, he championed the use of composite materials. He also supported the development of precision-guided weapons and their targeting systems and sensors.[15]

Space systems also fell within Flax's area of responsibility, and he oversaw the deployment of the Missile Defense Alarm System (MiDAS) space-based infrared sensor system for ballistic missile launch detection, the development of the Titan III family of launch vehicles, and the evolution of the early defense communications satellite systems including the Defense Satellite Communications System (DSCS), TACSATCOM, and the Global Positioning System.[15]

Flax concurrently served as the third director of the National Reconnaissance Office (NRO) from October 1, 1965, until March 17, 1969. In this role he oversaw major growth in NRO funding and personnel, and the production of signals intelligence collectors from space and promoted the development of real-time electro-optical imaging systems for reconnaissance satellites. He canceled short-lived low Earth orbit satellites in favor of longer-lived, more cost-effective ones in higher orbits with modules for returning film to Earth like the KH-8 Gambit 3 and KH-9 Hexagon. In the process, the NRO's signal intelligence share of the National Reconnaissance Program budget rose from 5 to 30 percent.[13][16]