如果该飞机的设计飞行缓慢，长期使用，低螺距螺旋桨看到最好的性能。

If the plane is designed to fly slowly, use a long, low pitch propeller to see the best possible performance.

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为了获得良好的抗汽蚀性能，对磁力泵叶轮采取低汽蚀余量设计措施，同时配置变螺距诱导轮。

In order to get a good performance on preventing cavitation, the impeller of magnetic driving pump is designed in low-NPSHR method and variable-pitch inducer is installed.

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