Aerodynamic Predictions, Comparisons, and Validations Using Missile DATCOM (97) and Aeroprediction 98 (AP98)

The U.S. Air Force Missile DATCOM (97 version) and the Naval Surface Warfare Center Dahlgren Division Aeroprediction 98 (AP98) are two widely used aerodynamic prediction codes. These codes predict aerodynamic forces, moments, and stability derivatives as a function of angle of attack and Mach number for a wide range of axisymmetric and nonaxisymmetric missile configurations. This study evaluates the accuracy of each code compared to experimental wind-tunnel data for a variety of missile configurations and flight conditions. The missile configurations in this study include axisymmetric body alone, body wing tail, and body tail. The aerodynamic forces under investigation were normal force, pitching moment, axial force, and center-of-pressure location. For the configurations detailed in this paper, these case studies show normal force prediction for both codes to have minimal error. Both AP98 and Missile DATCOM were effective in predicting pitching-moment coefficients, though at times limiting factors were necessary. Finally, both AP98 and DATCOM predict reasonable axial-force coefficients for most cases, though AP98 proved more accurate for the body-wing-tail and body-tail configurations evaluated in this study.