Beyond low earth orbit - An overview of orbit-to-orbit stages

New developments in upper stages are discussed. Tables revealing the dimensions, engine types, total thrust, weight, payload, and sponsor for developed and planned upper stages compatible with Space Transportation System (STS) or expendable launch vehicles are presented. An example of STS delivery capability to the Space Station at various orbital altitudes is provided. The use of aerobraking as the propulsion strategy for reusable stages is investigated. Various methods of controlling spent stages and maintaining a fragment free space environment are described. Storable propellant transfer systems and handling techniques for cryogens are studied.