The vertical tail size is not set to avoid spiral instability because this mode is not critical . 垂尾的大小不是根据避免螺旋不稳定来确定的。因为这种运动模态不是设计状态。
Interpretation of the relative importance of the higher modes is difficult since the higher frequencies tend to be closely spaced . 较高模态的相对重要性的说明也是困难的,因为较高的频率趋于挤在一起。
One significance of the eigenvectors is seen to be that they determine the values of the state variables in a characteristic mode . 本征矢量的重要意义之一是,它们决定了在一定模态中状态变量的相对值。
We find that there are reasonable approximations to all three modes, but the application of all such approximations must be made with caution . 我们发现,三种模态都有适当的近似式,但应用它们必须谨慎。