The Bridge To Space launch system

The Bridge-To-Space (BTS) is an advanced system concept that is designed to significantly reduce costs in delivering payloads to space. The BTS architecture provides the potential for achieving third generation launch system target costs of $100/lb to low earth orbit (LEO) and geosynchronous earth orbit (GEO). The BTS is comprised of two major elements: a long Space Elevator cable structure and an aircraft-like Sub-Orbital Launch Vehicle (SOLV), as shown in Figure I. A BTS operations overview is provided in the paper. Key operations include: payload transfer from the SOLV to the Space Elevator's Earth Transfer Station (ETS), payload translation along the elevator with a moving carriage platform, processing/transfer/release of the payload at the Apex Station (AS) as required, or payload release at the Space Transfer Station (STS). The paper provides background information on the two main factors that lower the "access to space" costs for the BTS system. These include reduced SOLV energy needed for payload delivery to the elevator, and the use of renewable or high efficiency energy devices to replace energy consumed during payload movement along the elevator. The remainder of the paper focuses on a discussion of preliminary dynamic analyses and control strategy recommendations for the orbiting Space Elevator, as well as the key environments (radiation and orbital debris) that drive design approaches.