To download as a PDF click here - US Army Center Of Military History

96 so u R c e s o f we a p o n sy s T e m s In n o v a T Io n In T h e depaR TmenT o f defense
Development Command, it did not prompt a massive reorganization of the inhouse
laboratories and testing facilities previously assigned to ARDC. To be
sure, the political fallout resulting from the launch of Sputnik in 1957 left its
imprint on the Air Force, primarily through an across-the-board expansion of
R&D programming in space-related fields. The laboratories, however, continued
to provide technical support to industrial contractors through the newly formed
System Command divisions. They also diversified into leading-edge fields
of science and technology relevant to the Air Force’s evolving requirements.
Representative examples to be discussed in this section include the expansion of
testing and evaluation functions at the Arnold Engineering Development Center
and Edwards Air Force Base, development of conventional armaments at Eglin
Air Force Base, work on artificial intelligence technologies at the Wright Air
Development Division and the Rome Air Development Center, and R&D on
high-energy laser and particle-beam weapons at Kirtland Air Force Base.
By the early 1960s, the mission of the Arnold Engineering Development
Center had changed to accord with the Air Force’s mandate to support the
Defense Department’s military space program. Consequently, the testing and
evaluation of air-breathing engines, which had dominated the technical activities
at Tullahoma for nearly a decade, faded quickly, surpassed by new programs
to develop rocket motors for missiles and spacecraft. In 1961, for example,
70 percent of the workload at Arnold was committed to the testing of rocket
propulsion systems for the AFSC Ballistic and Space Systems Divisions, the
Army, the Navy, NASA, and ARPA. The remaining 30 percent focused on
conventional air-breathing engines for aircraft and other near-surface weapons.
Between 1958, when the first test chambers in the original engine (later renamed
rocket) test facility were modified, and 1960, the number of rocket motor firings
increased sharply, from 15 to 761. Meanwhile, the increasing size and power of
propulsion technologies pushed the operational limits of the testing facilities
even higher. The engine test facility’s original thrust limit of 50,000 pounds had
quadrupled by 1961. New facilities under construction were expected to raise the
ceiling to 500,000 pounds and eventually triple that figure again, to 1.5 million
pounds, by the end of the decade. Among the major weapon systems tested at
Tullahoma during this period was the Air Force’s Minuteman intercontinental
ballistic missile. In addition to test firings of the solid propellant motors at
simulated altitudes, wind tunnel tests were conducted to evaluate the stability
of the entire missile assembly at velocities reaching Mach 8 (eight times the
speed of sound). Aerodynamic studies of the re-entry vehicle were carried out at
subsonic speeds and velocities exceeding Mach 20. Similar tests were completed
for the Army’s Redstone and Nike Zeus, NASA’s Mercury and X–15, and the
Navy’s Polaris programs.
Although the testing of rocket motors displaced similar work on air-breathing
engines, the rocket test facility still managed a substantial workload for aircraft
propulsion systems. Representative examples included tests to determine the
combustion efficiency, blowout and re-ignition limits, and component reliability
of the following: the J57 and TF33 jet engines manufactured by the Pratt and
Whitney Division of the United Aircraft Corporation for the Convair F–106