Hybrid Regional Aircraft: A Comparative Review of New Potentials Enabled by Electric Power

This article assesses the benefits of hybridization within the regional aircraft scale using a conventional twin-turbo propeller aircraft as reference. For a fair comparison, this reference aircraft was designed assuming a 2035 technology level. The propulsion system of the reference aircraft is analyzed along the mission and the phases of flight with low efficiencies are highlighted. Then the potential benefits of new power management through the use of secondary power generation systems but also through the variation of the size of prime movers are presented and discussed. In particular, the effect of the gas turbine size on its efficiency is studied. Finally, the article focuses on aerodynamic improvements enabled by new propeller or fan integrations and the associated concepts such as differential thrust, blown wing and boundary layer ingestion. For each topic, simplified analyses provide estimated potential of energy saving. These results can be used as indicators for selecting the most promising hybrid architecture concepts for a regional aircraft.