This paper reports about the parallelization of a module of a commercial airline flight-scheduling decision support system. The primary target platfom for this effort was a cluster of SCI-interconnected PCs. SCI's capability that enables a shared data programming model was one of the major arguments for this platform, besides the fact that Windows NT operated PCs become more and more important even for professional enterprise computing. Two additional platforms have been considered for evaluation purposes: a HP/ConvexSPP1200, the current parallel computing platform at Lufthansa Systems, as well as a 6-processor ALR PC server. The results are very promising in that it could be demonstrated that PCs are highly competitive in terms of absolute sequential performance and that the parallelized flight-scheduling module scales considerably better on the SCI-clustered PCs than on the ALR and even on the high-end HP/Convex multiprocessor
