Xie, YeSavvaris, AlTsourdos, Antonios2018-10-262018-10-262018-09-24Xie Y, Savvaris A, Tsourdos A. (2018) Sizing of hybrid electric propulsion system for retrofitting a mid-scale aircraft using non-dominated sorting genetic algorithm. Aerospace Science and Technology, Volumes 82–83, November 2018, pp. 323-3331270-9638https://doi.org/10.1016/j.ast.2018.09.022https://dspace.lib.cranfield.ac.uk/handle/1826/13582The paper presents the sizing of a hybrid electric propulsion system for a prototype aircraft. The main contribution of the paper is to apply multi-objective optimization in the retrofit of a mid-scale aircraft and investigate the fuel economy of the hybrid aircraft for a particular mission cycle. Using the Non-dominated Sorting Genetic Algorithm (NSGA), the fuel consumptions for different flight durations are minimized, which represent the optimal trade-off between fuel consumption and flight duration. With no compromise on endurance and range, the maximum fuel reduction of the retrofitted hybrid aircraft reaches 17.6%, by comparison with the prototype aircraft. The retrofitted aircraft achieves better cruising and climbing performance with the sized hybrid propulsion system. The novelty of the study is the proposal of a new non-dominated sorting algorithm—Benchmark based Non-Dominated Sort (BNDS) for the NSGA. BNDS can reduce the number of comparisons and the time complexity of the non-dominated sorting process. A constraint handling approach is also integrated into the BNDS/NSGA to address performance and mission requirements.enAttribution-NonCommercial-NoDerivatives 4.0 Internationalhttp://creativecommons.org/licenses/by-nc-nd/4.0/Mid-scale aircraftHybrid electric propulsion systemSizingNon-dominated sortNSGAArticle