But the technology already exists for a prototype of a fully reusable, aeroplane-like launcher, and its development costs need only be equivalent to about two space shuttle flights (about $1,000 million).

• 但是，人们现在已经具备了研制一种完全可以重复使用，外观像飞机的火箭样机技术，其研制费用仅相当于航天飞机进行两次宇宙飞行(大约10亿美元)。