PERFORMANCE AND TECHNICAL FEASIBILITY COMPARISON OF REUSABLE LAUNCH SYSTEMS - A SYNTHESIS OF THE ESA WINGED LAUNCHER STUDIES

The paper presents a synthesis of the performance and technical feasib ility assessment of 7 reusable launcher types, comprising 13 different vehicles, studied by European Industry for ESA in the ESA Winged Laun cher Study in the period January 1988 to May 1994. The vehicles compri sed single-stage-to-orbit (SSTO) and two-stage-to-orbit (TSTO) vehicle s, propelled by either air-breathing/rocket propulsion or entirely by rocket propulsion. The results showed that an SSTO vehicle of the HOTO L-type, propelled by subsonic combustion air-breathing/rocket engines could barely deliver the specified payload mass and was aerodynamicall y unstable; that a TSTO vehicle of the Saenger type, employing subsoni c combustion air-breathing propulsion in its first stage and rocket pr opulsion in its second stage, could readily deliver the specified payl oad mass and was found to be technically feasible and versatile; that an SSTO vehicle of the NASP type, propelled by supersonic combustion a ir-breathing/rocket propulsion was able to deliver a reduced payload m ass, was very complex and required very advanced technologies; that an air-launched rocket propelled vehicle of the Interim HOTOL type, alth ough technically feasible, could deliver only a reduced payload mass, being constrained by the lifting capability of the carrier airplane; t hat three different, entirely rocket-propelled vehicles could deliver the specified payload mass, were technically feasible but required rel atively advanced technologies.