AC311直升机自转下滑性能优化分析与处理

通过对AC311直升机自转着陆模拟试飞,验证其自转下滑性能满足CCAR27适航要求.在试飞过程中,飞行员发现发动机无动力时旋翼转速下降较快,在接地前“瞬时提距”时旋翼转速恢复较慢,较难完成自转着陆.为此,根据国际上比较贴近飞行员的定性意见的当量悬停时间,设计部门分析自转下滑性能偏低的原因,并通过换装参考直升机主桨叶进行对比试飞确认,提出了调整桨叶转动惯量的解决措施.这些措施经装机试飞验证取得了很好的实施效果.

AC311 Helicopter Autorotation Performance Optimization Analysis and Measure

In order to verification AC311 helicopter autorotation performance compliance with requirement ofCCAR27, it is necessary to do the autorotation simulate landing flight test. The rotor speed decrease too quickly under no power descent of the helicopter, and restore too slowly when increase blade collective pitch before touch the ground, that is difficult to complete the autorotation landing. Therefore, the design department evaluated and analyzed the reasons according to equivalent hovering time which was close to pilot＇ s qualitative advice, which validated through the comparison flight test with referenced blade. Brought out the moment of inertia adjustment measure, which was verified be effective by flight test.