Ingrid Dietlein

System Analysis for "Sharp-Edge" Re-entry Vehicles

Sharp-edged geometries for unmanned re-entry bodies are currently under investigation at DLR. During the phase 0 study an initial design for such a vehicle is developed. This paper presents the state of work in the design and describes briefly the process. The focus will be laid upon re-entry trajectories, aerodynamics and trimming as much as upon analysis of mass and centre of gravity.

Trim requirements and impact on wing design for the high-speed passenger transport concept SpaceLiner

An interdisciplinary study on the SpaceLiner orbiter is conducted focusing on the aspect of trimming and its impact on aerodynamical performance and structural design of the wing. Part of this study is to update the previously optimized aerodynamic shape taking into account the aspect of trim capability while maximizing the aerodynamic efficiency. This highly automated process results in a new preliminary definition of the aerodynamic shape of the SpaceLiner orbiter. A dimensioning abort case trajectory is defined following the recent update of the nominal return trajectory. Both serve as a starting point to the investigation of the trim requirement. The study confirms that the updated aerodynamic shape requires only small flap deflection angles for trimming, even under degraded conditions, and thus limits the impact on the lift-to-drag ratio. A structural analysis on the wing attests the importance of limiting the dimensioning flap deflection angles as the forces exercised by the flaps on the hinges can be considerable.