A german designer developed the idea for a rocket-propelled aerospace plane in the early 1940s.
A german designer developed the idea for a rocket-propelled aerospace plane in the early 1940s.
早在40年代初，一名德国设计师就曾提出了火箭推进航天飞机的设想。
A german designer developed the idea for a rocket-propelled aerospace plane in the early 1940s.
早在40年代初，一名德国设计师就曾提出了火箭推进航天飞机的设想。