论文部分内容阅读
美国空军从80年代起就开始进行单级入轨(SSTO)火箭的研究。此项研究的主要目的就是降低运输费用。
The United States Air Force has been conducting research into single stage orbiting (SSTO) rockets since the 1980s. The main purpose of this study is to reduce shipping costs.