The determination of aerodynamic coefficients for complex high-speed vehicles still requires experimental measurement. This paper details the development of the free-flight measurement technique within the University of Oxford High Density Tunnel. In particular, a novel image processing technique is developed for calculating the position of the model from high-speed video. This study focuses on the measurement of high Reynolds number experimental aerodynamic data for a subscale model of the Skylon space plane of Reaction Engines. Testing was undertaken at a Mach 7 test condition replicating flight at an altitude of 63.5 km. Results for lift, drag, and pitching moment coefficients were obtained over a range of angles of attack. Lift coefficient was nearly linear over the range of angles of attack tested, and drag coefficient was parabolic in shape, but sensitive to model yaw. The vehicle was also shown to be statically unstable, a common characteristic of canard configuration vehicles.

复杂高速车辆空气动力系数的确定仍需要实验测量。本文详细介绍了牛津大学高密度隧道内自由飞行测量技术的发展。特别是，开发了一种新颖的图像处理技术，用于从高速视频中计算模型的位置。本研究的重点是测量反应发动机 Skylon 空间平面子比例模型的高雷诺数实验空气动力学数据。测试是在 7 马赫的测试条件下进行的，在 63.5 公里的高度复制飞行。升力、阻力和俯仰力矩系数的结果是在一系列攻角范围内获得的。升力系数在测试的攻角范围内几乎呈线性，阻力系数呈抛物线形，但对模型偏航敏感。该车辆还被证明是静态不稳定的，这是鸭式配置车辆的一个共同特征。