The validation of fast-time air traffic simulations in practice

Computer simulation is an important tool in the development of air traffic control procedures and systems, ranging from fast-time simulations (requiri ng no manual intervention) through a variety of real-time, controller-in-th e-loop simulations of increasing size and fidelity. This paper presents a c ase study of an airspace re-design project and uses this to illustrate a nu mber of issues about the validation of fast-time simulations. The two princ ipal observations are: (1) that there are specific circumstances when 'seei ng is believing', that is, when it is appropriate to use visualisation of s imulations as part of validation; and (2) that the distinction between vali dation activities and generating project results is not as sharp as descrip tions in the literature, typically show.