In the second half of the 1970s and the whole 1980s there was a great interest in flow field solutions for space vehicles and military missiles flying at supersonic and hypersonic Mach numbers. With the computer power (CPU efficiency and storage capacity) at that time numerical solutions of the time dependent Navier-Stokes equations for complete three-dimensional configurations could not be achieved. Therefore fluid dynamic scientists did search for more efficient procedures to integrate the governing equations. One option was to employ so-called Space marching methodspace marching methods, which are applicable, if the component of the velocity vector in marching direction is supersonic (valid for inviscid flowTannehill, J.C. andBuelow, P.E. viscousIevalts, J.O. flowLawrence, S.L. beyond the subsonic sublayer) andHirsch, C. ifTannehill, J.C. inVenkatapathy, E. viscousRakich, J.V. flowRakich, J.V. noVenkatapathy, E. flowTannehill, J.C. reversalPrabhu, D. existsChaussee, D.S. [1–5]. For the Euler equations the condition for a space marching procedure is just that the velocity component with respect to the marching direction is supersonic. Then, if the time derivatives are dropped, the Euler equations are hyperbolic in space. For the Navier-Stokes equations also the time derivatives are cancelled and the viscous terms in marching direction are neglected, which leads to a mixed hyperbolic-parabolic system.