13 Reasons a Cost Estimate during a Concurrent Engineering Study could go wrong

During early phase spacecraft design, the concurrent engineering (CE) approach is proven to be very efficient. But the condensed and iterative nature of CE sessions can also make life hard for a cost estimator. This work discusses 13 problem areas experienced or observed mainly during one-week, inter-disciplinary space system design studies and provides practical examples on how to tackle them, e.g. how to handle rapid data changes, wrong expectations and a diverse engineering team.