National Aeronautics and Space Administration (NASA) researchers set up instrumentation on a 0.037- scale model of a Saturn booster in the 8- by 6-Foot Supersonic Wind Tunnel at the NASA Lewis Research Center. In October 1960 Lewis researchers John Allen and Robert Wasko began a 14-month investigation of the eight-engine booster’s base heating in the tunnel. The model resembled the Saturn C-1, but only the afterbody totally mimicked the C-1.
The over-heating of the lower end, or base, of the booster can cause the engines to fail or introduce aerodynamic concerns. Base heating results from the rocket engines’ exhaust heat, the recirculation of that heat into the base, and the burning of combustibles. Large boosters, like the Saturn, employed clusters of rocket engines that add to the complexity of the base heating problem.
The 8- by 6-foot tunnel investigations studied the Saturn at speeds from Mach 1.0 to 2.0 using liquid oxygen and JP-4 as propellants. Researchers found that the use of cooling air scoops and external flow deflectors produced significant decreases in base heating.