Value Assessment for Aero-engine Design: A Case Study on Large Turbofans

,The paper addresses the main research question of “How can an aero-engine manufacturer assess engine design from an engine performance and total value perspective?” The relation of as many technical engine parameters as possible was studied. The objective was to obtain information about design strategy in aeroengines and which design efforts do contribute most to engine value. The value assessment and validation by the case study used an attribute weighting technique based on correlation analysis of nine attributes of 103 engines. Stronger correlation proofed to be an indication of importance of an attribute. With normalization of the correlations of nine attributes a weighting was obtained to measure operational performance of aeroengines in order to indicate value optimization. A three cases were selected from these 103 engines. One group of five engines of each of the three companies. From the assessment it appeared that pressure ratio, airflow and bypass ratio were the most important attributes. Initially the financial performance of the OEM seems not to be directly related to the value of the engines produced. However after applying the weighing based on the correlations the product performance and financial performance of the companies show a much better relation. A value assessment was developed and validated with the available data and proofed to be a useful instrument to assess value and design strategy. The value assessment is expected to assist design strategy by indicating which attributes require most attention. This is important because higher product value benefits OEM, customer and supplier. The value assessment can be concluded to be the answer to the research question of how to better assess engine design. The main recommendations following from this research are: to implement VDD methodologies such as this value assessment, to study why seemingly high product performance does not lead to financial performance; and in general: to apply the value assessment to other areas within the aerospace industry and beyond.

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