Flight Techniques for Determining Airplane Drag at High Mach Numbers

The measurement of total airplane drag in flight is necesssry to assess the applicability of wind-tunnel model data. The NACA High-Speed Flight Station has investigated and developed techniques for measuring the drag of high-speed research airplanes and current fighter-type airplanes. The accelerometer method for determining drag was found to be the most satisfactory method for research work, because it is the only method permitting a complete coverage of the Mach number and angle-of attack capabilities of an airplane.