Mission safety concept for a two-stage space transportation vehicle

Mission abort scenarios are treated for a two-stage space transportation system with a range cruise capability. A basic topic is the number of emergency landing sites required in case of a mission abort. It is shown that, besides the launch site, two emergency landing sites are sufficient for aborts caused by single engine failures. This holds for the transportation system as a whole and for each stage in case of a failure at any time during the flight. Particular emphasis is placed on an all engine blow out malfunction of the carrier stage during the highly dynamic separation maneuver. Furthermore, minimizing the activity of the aerodynamic control surfaces during mission abort is also treated. In addition, the required emergency landing site for a mission abort from orbit is also considered.