The design of modern aircraft engines relies heavily on technological advances. In response to pressures from customers and competitors for improvements in efficiency of performance, scheduling and overall cost reduction, manufacturers are being forced to consider innovative solutions. These innovative solutions often come with higher risks and the need for risk assessment, especially at the early product and service design stage, becomes a necessity. Decisions at an early stage of the lifecycle, e.g. during the conceptual design, are made with relatively low confidence, but such decisions greatly influence the overall product and service development. It is, therefore, critical to define the risks involved in order to help designers to make informed decisions. This research project investigates the risk and uncertainties in delivering products to meet top-level business requirements. The aim is to improve the existing process of setting business requirements and the current design approaches to achieve an optimised system design. This project also examines different approaches in assessing the risk of product and service delivery. To achieve that, a dedicated software tool, based on Weibull distribution function reliability model, has been created. An example of Rolls-Royce Civil Large Engine (CLE) gas turbine design process is used in this research as the case study. An analysis of the gap between the current design achievements and the targeted business requirements of a new product is performed at whole engine, module and component level. Further comparison of the new product business requirements, the novelty in the design and the historical reliability data is used to define and assess the risk of new product delivery.

Outgoing