Product platforms and platform-based product development provide a cost-effective means for generating sufficient product variety for the market to suit the varied demands of today's customers. A genetic algorithm (GA)-based approach for product family design is adopted in this research for optimizing a product family to help resolve the inherent trade-off between platform commonality and individual product performance within the family. One of the challenges encountered in our work is the enormous amount of information that is generated from the GA-based approach. In particular, the GA-based approach allows us to explore multiple families based on multiple platforms, and effective visualization strategies are needed to help identify the best solution. In such situations, multi-dimensional visualization becomes an effective method to synthesize large numbers of complex designs in a short time without losing any essential information. In this paper we explore visualization strategies are presented to support the product family design optimization process and their applications are demonstrated with a General Aviation Aircraft example.