Sling-on-a-Ring: Structure for an elevator to LEO

Various proposed space elevators may bypass the financial and environmental limits on rocket technology, but all have their own problems. A Low-Earth-Orbit (LEO) rotovator-based space-elevator version called “sling-on-a-ring” may overcome them. This mass-lifting system uses the spatial stability of an orbital ring, accessorized for transfer and storage of momentum and electrical power. A high-tensile-strength equatorial circum-terra loop of colossalcarbon tube (CCT) fiber has solar-power and station-keeping units and rotating sling modules attached. Long sling assemblies (∼600 km) periodically descend from the orbital ring into the atmosphere (to ∼13 km). At perigee, the sling's rotational tip velocity almost cancels the orbital ring's velocity relative to Earth's surface. Split-second timing detaches a ∼10-ton payload from an ordinary aircraft and jerks it into space by sling and ring momentum, with the proven specific strength of CCTs now under development. This system eliminates the immense mass in space of other space-elevator systems, but needs extremely-long (100 km) compressive members. Conceptual analysis for mass reduction of these structures is the subject of this paper.