美国空军和波音公司的惯性上面级已成功地满足了航天飞机飞行任务要求,在51-C 航天飞机任务飞行期间,把国防部卫星送入地球同步轨道。惯性上面级是在发现者号航天飞机发射16小时后从轨道器有效载荷舱释放入轨。定时装置使惯性上面级中第一级发动机点火,此时轨道器至少在10 The inertial upper classes of the USAF and Boeing have successfully met the space shuttle mission requirements to send DoD satellites into geosynchronous orbit during the mission’s 51-C mission. The inertial upper plane was released into orbit from the orbiter payload bay 16 hours after the Discovery shuttle was launched. The timing device ignites the first stage engine in the inertial upper stage, with the orbiter at least 10 at this time