NASA Lanslev Research Center Hamit&, V i r g i n i a Abstract Flow f i e l d phenomena associated with a supersonic j e t i s s u i n g upstream i n t o a hyperv e l o c i t y flow f i e l d were investigated experimentally i n support of a new space vehicle aerobraking concept developed by Boeing f o r O r b i t a l Transfer Vehicles (OTV's). Tests were made on OTV models i n the NASA Langley 22 inch, Mach 20 helium tunnel w i t h j e t e x i t Mach numbers from 1.0 t o 6.18 and b a l l u t e h a l f angles of 450 and 60°. Force data were taken a t zero angle o f a t t a c k t o determine the effect of b a l l u t e angle, j e t Mach number and j e t flow r a t e on v e h i c l e drao. Bow shock