在航天飞机计划中,经常提到但却很少讨论的一个伙伴是美国国防部,它每年的开支是NASA的几倍。到90年代初期,在航天飞机的487次飞行中,军用飞行任务预计要占三分之一。航天飞机计划常常以国家安全的需要为名,作为它存在的护身符,而军事飞行又往往披上神秘的外衣。 One of the most frequently mentioned but seldom discussed partners in the shuttle program is the U.S. Department of Defense, which spends several times a year on NASA. By the early 1990s, military missions were expected to account for one third of the 487 flights of the space shuttle. Space shuttle programs are often named after the needs of national security as the amulets that exist for them, and military flights are often clothed in mystery.