1 Quantitative and Qualitative Cost Estimating for Engineering Design Authors: Rajkumar Roy, Sara Kelvesjo, Sara Forsberg, Chris Rush Correspondence Address: Dr. Rajkumar Roy, Department of Enterprise Integration, Building 53, School of Industrial and Manufacturing Science, Cranfield University, Cranfield, Bedford, MK43 OAL, United Kingdom. Email: r.roy@cranfield.ac.uk Abstract This paper describes the development of a cost estimating methodology for predicting the cost of engineering design effort during the conceptual stages of product development. The research was carried out within a large European aerospace manufacturer whose traditional costing practices had become outdated. The main objective was to generate a suite of technical Cost Estimating Relationships (CERs) that integrate both quantitative and qualitative, non-recurring airframe engineering input, for the design process. Both the quantitative and qualitative design activities were separated during the CER development. At the end of the development process they were integrated to produce a final CER. The results demonstrate that these newly generated CERs can predict future design effort required, based on the typically limited product definition at the conceptual design stage. 1 Introduction Aerospace industry is moving toward a system of concurrent or simultaneous engineering to improve competitiveness. Concurrent engineering reduces lead-time by