Tools for parallel systems today range from specification over debugging to performance analysis and more. Typically, they help the programmers of parallel algorithms from the early development stages to a certain level of program optimization. However, in HPC (High Performance Computing) today the end-user of massively parallel CFD (Computational Fluid Dynamics)-programs has little or no support in his work. The scientific engineer who often runs his application on a parallel computer somewhere in the WAN (Wide Area Network) and visualizes the enormous amounts of simulation data on a graphical workstation in his LAN (Local Area Network) has needs which are by far not covered by state of the art visualization systems. The tool proposed here follows a strategy which differs completely from existing, batch-oriented, and strictly sequential methods of the working process in the application cycle of parallel HPC applications. It allows both on-line visualization and interactive program ...