Retrofitting an existing helicopter with eVTOL capabilities: challenges and opportunities

Abstract

Over the past decade, considerable work has also been done on the design, development, and deployment of eVTOL vehicles for civilian and military use. Relatively less work has been done on retrofitting existing helicopters with eVTOL capabilities. Keeping the existing airframe while implementing changes to the structural elements, rotors, and other components such as engines and drive train presents a significant challenge. For commercial helicopters, the cost and gross weight of the system, and the impact of design changes on the performance of the vehicle must also be addressed. In this study, we examine the environmental impact of retrofitting notional helicopter configurations based on the highly successful MBB Bo 105 helicopter, and its successor, the EC 135 helicopter. The advances include an improved rotor, fuselage drag reduction technologies, and an allelectric system. Results are presented for the impact of these modifications on the system weight, range, and endurance. The paper also discusses challenges and opportunities associated with these design modifications.