The test model was made and an experiment was done to verify the prediction of the autorotation state characteristics for a high-speed rotorcraft scheme.

针对某一高速直升机方案的自转状态，本文设计和建设了试验模型和试验设备，进行了相应的实验研究。

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The investigation found that the autorotation training the pilot received was not representative of an actual engine failure at cruise speed, which likely contributed to his failure to successfully execute the maneuver.

CNN: Pilot texting a factor in deadly copter crash