短語詞組短語ballistic c trajectory 彈道Traceless Ballistic Trajectory 彈道無痕external ballistic trajectory 外彈道ballistic trajectory condition 彈道環(huán)境ballistic trajectory characteristics 彈道特性ballistic trajectory solution 彈道解算ballistic minimum velocity trajectory 速度最小的慣性飛行彈道 返回 ballistic trajectory