Conceptualisation and subsequent validation are essential for future aerospace vehicle design. In this process, theoretical analysis is often constrained imposed by numerical and physical experimentation limitations. This is where the incorporation of flight and other simulation packages as new tools of real-time investigation, for determining design drivers, estimating flight performance, likely operational scenarios and manufacturing strategies can become so useful. For the past few years, we have been exploring the effectiveness of this new tool at the University of New South Wales. The results appear to be highly promising. In this paper, we outline the various stages of the methodology and demonstrate through a test case how the simulation activity can be implemented in the overall design process. It appears that the incorporation of simulation into the design process has the prospect of ushering in a new era for future advanced project aerospace design that will find application far beyond aerospace industries.