Electrified and Hybrid Propulsion Systems for Vertical Take-Off and Landing Aircraft

The market for unmanned aerial vehicles is expanding the use of hybrid-electric and fully electric technologies, which contributes to the growth of urban air mobility and cargo delivery, despite existing technological and infrastructure challenges. Vertical takeoff and landing aircraft are classified by types of propulsion systems, including traditional helicopters and systems with separate lift and thrust, as well as distributed systems. Among the concepts of hybrid propulsion systems, there are three main configurations: the classic with side rotors, a configuration with separate propellers, and a serial configuration with tilting wings. Each of these requires a comprehensive approach to the management and integration of subsystems, including energy storage and electric drives with thermal regulation systems. Major research is focused on optimizing distributed propulsion systems, which is particularly important for urban air mobility and cargo transport. The implementation of hybrid-electric systems allows overcoming limitations associated with battery technology, increasing flight range and reducing harmful emissions. Hybrid systems that combine thermal machines and batteries open new opportunities for energy savings and reduced operating costs. Gas turbine engines and the use of liquefied natural gas can be considered the most efficient solution for minimizing operational costs.