为什么直升机旋翼轴会有一个构造前倾角?
参考答案:
直升机旋翼轴有一个构造前倾角的时,在巡航状态,机身地板能大致处于水平,不但可以改善驾驶员工作条件,还可以减小机身阻力。
--- Are your family ready for rafting?
---Yes, I really want my children to experience that they are young
A.\
B.while
C.unless
D.if