Propulsion and energy systems aren't at the point where Roughead's dream is feasible.

推进和能量系统都还没有达到能实现拉夫黑德梦想的水准。

youdao

Propulsion and energy systems aren't at the point where Roughead's dream is feasible.

推进和能量系统都还没有达到能实现拉夫黑德梦想的水准。

youdao