Aerodynamic tests in support of the Columbia accident investigation were conducted in two hypersonic wind tunnels at the NASA Langley Research Center, the 20-Inch Mach 6 Air Tunnel and the 20-Inch CF4 Tunnel. The primary purpose of these tests was to measure the forces and moments generated by a variety of outer mold line alterations (damage scenarios) using 0.0075-scale models of the Space Shuttle Orbiter. Simultaneously acquired global heat transfer mappings were obtained for a majority of the configurations tested. Test parametrics included angles of attack from 38 to 42 deg, unit Reynolds numbers from 0.3 x 10(exp 6) to 3.0 x 10(exp 6) per foot, and normal shock density ratios of 5 (Mach 6 air) and 12 (CF4). The damage scenarios evaluated included asymmetric boundary layer transition, gouges in the windward surface thermal protection system tiles, wing leading edge damage (partially and fully missing reinforced carbon-carbon (RCC) panels), deformation of the wing windward surface, and main landing gear and/or door deployment. The measured aerodynamic increments for the damage scenarios examined were generally small in magnitude, as were the flight-derived values during most of the entry prior to loss of communication. A progressive damage scenario is presented that qualitatively matches the flight observations for the STS-107 entry.
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机译：在美国宇航局兰利研究中心的两个高超音速风洞，20英寸马赫6空气隧道和20英寸CF4隧道中进行了空气动力学测试，以支持哥伦比亚事故调查。这些测试的主要目的是使用0.0075比例的航天飞机轨道飞行器模型，测量由各种外模线变化（损坏情况）产生的力和力矩。对于大多数测试配置，同时获得了全局传热映射。测试参数包括攻角从38度到42度，雷诺数从每英尺0.3 x 10（exp 6）到3.0 x 10（exp 6），以及正常冲击密度比为5（6马赫空气）和12（CF4） ）。评估的破坏情景包括不对称边界层过渡，迎风面热保护系统砖中的凿子，机翼前缘损坏（部分和完全缺少增强碳碳（RCC）面板），机翼迎风面的变形以及主起落架和/或门部署。对于所检查的损害情景，所测得的空气动力学增量通常较小，在失去交流之前的大多数进入过程中，来自飞行的值也是如此。提出了一种渐进式损坏情景，该情景与STS-107入口的飞行观察定性匹配。
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