The development of Urban Air Mobility (UAM) has led to the introduction of various electric vertical takeoff and landing (eVTOL) aircraft configurations, which plays a crucial role in determining performance. This paper systematically compares two typical eVTOL configurations, lift + cruise and tiltrotor, under the context of a UAM mission with a payload of 200 kg and a range of 200 km. Employing a comprehensive aircraft sizing and mission analysis framework, the study evaluates weight, energy consumption, power requirements, and noise characteristics. The results show that the tiltrotor outperforms the lift + cruise in terms of maximum takeoff weight (MTOW), cruise aerodynamic efficiency, and mission energy consumption, mainly due to the avoidance of non-operating lift systems during cruise, thus reducing aerodynamic and weight penalties. However, the tiltrotor presents increased complexity in propulsion system design and mode transition. Noise analysis highlights that the lift + cruise generates significantly higher sound pressure levels (SPL) during vertical takeoff and landing (VTOL) due to high disk loading rotors, posing a critical urban constraint. A sensitivity analysis of battery energy density indicates that, although improvements in energy density enhance overall performance for both configurations, the relative performance gap remains stable across various energy densities. Ultimately, the configuration type plays a dominant role in determining aircraft performance. This study provides quantitative insights for eVTOL configuration selection and early-stage UAM aircraft design.
Chen et al. (Mon,) studied this question.