A Conceptual Design Methodology for e-VTOL Aircraft for Urban Air Mobility

Abstract

Recent progress of electric systems has raised attention towards hybrid-electric and full-electric aircraft. Nevertheless, the current low battery energy density limits the application of these propulsive architectures to large transport aircraft. In the context of the general aviation category, full-electric aircraft for the so-called Urban Air Mobility scenario are gaining increasing interest. These air taxis, also called e-VTOL, are conceived to exploit vertical take-off and landing capabilities, to carry people from one point to another, typically within the same city. In this paper, a new conceptual design methodology for urban air vehicles is presented and applied to an innovative convertiplane, called TiltOne, based on a box-wing architecture coupled with tilt-wing mechanisms. Several TiltOne configurations have been designed according to the current regulations imposed by European Union Aviation Safety Agency, and sensitivity analyses have been carried out on the varying main design parameters, such as wing loading and propellers’ disk loading, as well as main top-level aircraft requirements. The results provide an overview for today’s operational capabilities of such aircraft and, in addition, depict possible scenarios for a near-future horizon, based on the assumption of increased performance levels for the electric powertrain components. In such scenario, two different concepts of operations are analysed and discussed: the first is based on a given design range, long enough to cover the urban distances; the second is conceived to exploit the capability of flying multiple shorter missions with a single battery charge. The designed TiltOne configurations derived from these different approaches are presented, highlighting their potential capabilities and possible drawbacks.

Design and Analysis of VTOL Operated Intercity Electrical Vehicle for Urban Air Mobility

“…Giuseppe et al [14] presented a new conceptual design methodology for the tilt-wing type eVTOL known as 'TiltOne'. Two tilt-wing configurations, known as "single mission" and "multi mission", were considered.…”

Preliminary Sizing of an eVTOL Lift-Cruise Aircraft

“…The lift-cruise configuration combines features of both rotary-wing (RW) and fixed-wing (FW) configurations. This configuration typically includes a combination of horizontal and vertical thrust capabilities, which allows the aircraft to take-off and land vertically like a rotorcraft and then transition to forward flight like a FW aircraft [4][5][6]. The lift-cruise configuration is optimal for medium ranges and structurally less complicated than tiltrotors.…”

Conceptual design and sizing optimization based on minimum energy consumption of lift-cruise type eVTOL aircraft powered by battery and fuel cell for urban air mobility

“…The concept of UAM is not new (its first examples date back to the 1950s [2]) but continued only as a helicopter service until recently when its applicability to UAM has increased due to the growing concerns on traffic congestion, noise, and harmful emissions. Companies such as Uber Elevate, Hyundai, eHANG, Boeing-Aurora Transmative, Grab and BLADE carry out research and development activities on economic feasibility, safety, and critical design issue in UAM passengers transportation in metropolises [3]. In fact, for UAM to become widespread, it needs still improvement in terms of operation and maintenance cost sustainability, public trust and acceptance, infrastructure suitability, and aircraft range [4].…”

“…However, due to their higher power consumption, they are generally more suitable for short-distance passenger transportation [6]. Since lift-cruising, tilt-wing, and tilt-rotor type aircraft have a fixed-wing, their lift forces are higher than rotarywing VTOL aircraft [3]. The tilt-rotor and tilt-wing aircraft require special equipment as they change their mode during flight.…”