Models and Methods at ONERA for the Presizing of eVTOL Hybrid Aircraft Including Analysis of Failure Scenarios

With the progress of electric power generation systems (hybrid propulsion or all-electric), it becomes now possible to make fly new electric Vertical Take-Off and Landing (eVTOL) concepts of aircraft. This step forward is a technology rupture which should allow breaking through the locks preventing from using more the VTOL aircraft. Indeed, the use of rotorcraft, especially in areas with high population density, is still limited by the public acceptance mainly because of the noise and the risk of crash in case of failure. A new design paradigm is emerging pushing to use distributed electric lift/propulsion systems composed of rotary wings (propeller or rotor blades) and electric motors combined or not with fixed wings. Numerical models and methods are needed for exploring this new design space. This paper presents the extension of the CREATION numerical workshop and associated simulation tools in order to be able to deal with the predesign of eVTOL. A methodology for the presizing of eVTOL is proposed addressing the most demanding flight conditions with thruster(s) failure. The application of these models and methods is illustrated on a new eVTOL concept combining rotary wings and fixed wings.