Moon & Mars Orbiting Spinning Tether Transport - Tethers Unlimited

Appendix F: Tether Boost Facility Design Final ReportPolitical and legal feasibility drive the mission requirement for avoiding collisions withother spacecraft. U.S. and international organizations would take political or legalaction to block the launch of a system that would pose a hazard to other spacecraft or topeople on Earth.Requirement NameValuePayload Mass 5000 kg at IOC, cangrow to follow marketPickup orbit300 km equatorialRelease orbitGTORelease insertion < Delta IV/Ariane 5errorPayload environment < Delta IV/Ariane 5Turnaround time 30 daysMission life 10 years +Collision avoidance 100% of trackedspacecraftOperational orbit 15 dayslifetimePayload pickup 99%reliabilityTable 1.1. Top-Level Mission Requirements.Technical feasibility drives mission requirements for nominal pickup orbit andoperational orbital lifetime. The 300 km circular pickup orbit is high enough that dragwill not greatly complicate the rendezvous calculations, nor is the payload in danger ofde-orbiting quickly if the tether misses one or two grapple attempts, but it is low enoughto be relatively inexpensive for launch vehicles to reach. The 15-day operational orbitallifetime for the tether gives a reasonable amount of time for operators to debug andcorrect problems if a failure makes the system temporarily unable to reboost itself.F-6