Overview of the challenges of alternative propulsion systems applied to business aircraft

Abstract: In order to reduce greenhouse gas emissions and reach the 2050 net-zero emissions target, the aviation sector is looking towards new propulsion architectures, such as electric, hybrid-electric, and hydrogen powertrains. The integration of these kinds of new powertrain technologies has a significant impact on aircraft performance. The loss of performance typically consists of a range reduction, a reduced payload capacity, a lower cruise speed than the baseline aircraft, etc. Cost in capabilities does not have the same impact depending on business or commercial aviation, as these are two radically different markets. The travel routes for a given airline are constant and well-known, and a loss of aircraft performance capability may therefore be acceptable, this is not the case for business aviation due to hard operational constraints. The operational constraints of business aircraft are reflected in a higher cruise speed than commercial aviation, a flight altitude above commercial traffic, a long-range capability, high volume and comfort of the cabin, the capability to takeoff and land at small regional airports, and so on. Since the operational flexibility of the aircraft is at the heart of the business aviation market and dependent on these performance indicators, these requirements are necessary to maintain the high level of competitiveness of the aircraft. The literature mainly focuses on the greenhouse gas emissions reduction of retrofitted aircraft without considerations for keeping the same level of performance as the baseline aircraft. As business aviation is expected to experience growth in deliveries over the next few years, the assessment of the impact of alternative propulsion systems on the performance of aircraft is crucial. Since all new propulsion technologies for the mitigation of aviation carbon footprint have drawbacks, the integration of these systems should result in an acceptable trade-off between the operational capabilities of the aircraft and CO2 emissions reduction. This paper presents the cost in performance and the key challenges of alternative propulsion system integration of business aircraft. The analysis focuses on three main architectures, the all-electric powertrain, hydrogen-powered aircraft, and parallel hybrid powertrain. The objective is to provide an overview of business aircraft requirements, the impact of alternative propulsion systems on such aircraft, and the key challenges to meet the operational constraints of the business aviation market.Résumé de la communication présentée lors du congrès international tenu conjointement par Canadian Society for Mechanical Engineering (CSME) et Computational Fluid Dynamics Society of Canada (CFD Canada), à l’Université de Sherbrooke (Québec), du 28 au 31 mai 2023