Flow fields around conical single-stage reusable vehicle configurations with aero spike nozzle ramp are computationally Investigated at various angles of attack under subsonic to supersonic flows using the RANS (Reynolds-aver aged Navier-Stokes) simulations for conceptual design. Geometric parameters of the ramp are changed for the Investigation of their effects on the aerodynamic characteristics. The computational results showed that the ramp attachment has little effect on the aerodynamic characteristics at all the Mach numbers at the angles of attack at which the ramp is immersed in the separated wake. At higher angles of attack where the free-stream hits side of the body, the ramp attachment results in the increase of lift and drag coefficients and the configurations with larger ramp have larger lift and drag coefficients at supersonic flow. At tall-first conditions, the ramp attachment results in the decrease of lift and drag coefficients and the configurations with larger ramp have smaller lift and drag coefficients at all the Mach numbers. Strong Mach number dependencies appear by the existence of circulation region in the windward of the ramp.