4. Lesson: Program Reserve
Plan adequate reserve in resources, schedule, and performance.
Background:
Since these three variables can be traded off, initial plans should recognize the possibility of needing all three. For example, in Skylab, the contingency launch vehicle and CSM were added to the program (four sets of hardware were provided for three manned missions) to ensure that three missions could be accomplished even if a launch failure had occurred on one of the three planned missions. It was recognized, however, that in the event the program costs escalated, that hardware could be terminated with a resultant cost reduction. The reduction in program content would not have been large.
A similar approach was successfully used in the Gemini Program where 15 launch vehicles were planned for 12 missions. As a cost avoidance measure, the three back-up vehicles were cancelled.
These lessons learned are from SKYLAB LESSONS LEARNED AS APPLICABLE TO A LARGE SPACE STATION, A dissertation submitted to the faculty of The School of Engineering and Architecture Of the Catholic University of America For the Degree Doctor of Engineering by William C. Schneider, Washington, D.C., 1976.
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