Experimental studies on a liquid fly-back-booster configuration (LFBB) in wind tunnels

Abstract

In the frame of German future space transportation technology and research program ASTRA a concept of a reusable winged liquid fly-back booster (LFBB) is under investigation. It has two booster stages attached to the expendable Ariane 5 core stage. During the first phase of the study several empirical and numerical analysis methods were used with respect to the configuration definition. The subsequent design loop required a more detailed investigation including wind tunnel measurements along the complete trajectory from separation at hypersonic speeds down to the subsonic fly-back cruise regime. Tests were performed not only creating a complete aerodynamic data set for trim and balance in longitudinal motion but also achieving a deeper understanding of the characteristics of the flow field of this vehicle including the influence between the canards and the wing. Measurements were carried out in the DLR trisonic wind tunnel TMK (0.5 < Ma < 4) and the hypersonic wind tunnel H2K (Ma = 6.0 and Ma = 7.0). The model angle of attack was varied from -2° to +8° and from -2° to +38° in TMK and H2K respectively. The angle of side slip was varied between 0° and 5°.