But I know my basic problem is control the vertical speed.

不过，自己知道自己最根本的问题还是在于对垂直速度的控制。

youdao

The takeoff is in essence an action that creates vertical speed.

踏跳动作的实质是创造垂直速度的过程。

youdao

With altimeter, users can get to know the altitude and vertical speed.

与高度表，用户就可以知道高度和垂直速度。

youdao

This number is calculated by considering both horizontal speed and vertical bounce of a tennis ball off a court.

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Finally, AgustaWestland surprised the HeliExpo crowd by revealing that it has been secretly testing an electrically powered tiltrotor, mixing the versatility of a vertical takeoff and land helicopter with the speed and range of a fixed-wing aircraft.

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Part of that need will be met in the future by a new generation of rotorcraft, including the revolutionary MV-22 tiltrotor that combines the vertical agility of a helicopter with the speed and range of a fixed-wing plane.

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