Ground-Effect Characteristics and Centerline Pressure Distributions for a Hypersonic Configuration

Aircraft that operate at hypersonic speeds must adhere to stringent aerodynamic design restrictions. Typical designs incorporate complete integration of the fuselage and propulsion system. Unfortunately, these designs tend to perform poorly at subsonic speeds and demonstrate unfavorable propulsion/aerodynamic interactions when operated in ground effect for takeoff. Significant work has been done to quantify this interaction including pressure measurements using a two-dimensional model. This paper presents basic aerodynamic coefficients and centerline lower surface-pressure distributions that were measured on a three-dimensional hypersonic configuration of the National Aero-Space Plane.