Dear Colleagues,

With the emergence of electric propulsive technologies in the past decade, electric vertical takeoff and landing (eVTOL) aircraft have gained an increased interest, which paves the path for sustainable urban air mobility (UAM) and advanced air mobility (AAM). eVTOL aircraft are characterized by distributed electric propulsion, which enables them to have high safety redundancies and zero-emission, thus providing access to convenient UAM/AAM. Nevertheless, challenges also arise from the implementation of UAM/AAM aircraft, which include, but are not limited to:

(1) Efficient operational strategy of sustainable UAM/AAM. UAM/AAM missions with complex airspace and strict safety requirements necessitate the use of eVTOL aircraft. It is of particular interest to investigate operational strategies that guarantee the safety level while reducing noise and saving energy.

(2) Multi-physical nature of eVTOL aircraft. The electric aircraft is governed by electric propulsive constraints that stem from power conservation among energy supply units (lithium-ion batteries, fuel cells, hydrogen cells, and solar cells), motors, and propellers/fans. The complex effects need to be reflected in the simulation model with suitable fidelity, which, in turn, serves as the cornerstone for improving operational efficiency.

(3) Practical energy management strategy. The endurance of eVTOL aircraft is significantly limited by state-of-the-art energy supply technology. Hence, there is an urgent need to provide an efficient energy management strategy to enlarge the coverage of vehicles, which calls for the integration of advanced algorithms into UAM/AAM systems.

(4) Energy-optimal scheduling of the UAM/AAM fleet. Unlike the current operational mode of airspace, which presets allowable routines for agents, the flexible use of airspace is applied. Specifically, FUA assumes airspace as a “continuum” where all the user requirements are satisfied to the greatest possible extent. Thus, it is of great importance to schedule the whole UAM/AAM fleet in one airspace with energy-optimal and safe operational routines.

(5)  Advanced and intelligent control laws are facilitating future applications. The envisioned widespread application of eVTOL aircraft necessitates more advanced and intelligent control laws that help reduce training costs and ease the burden on the pilot. The artificial intelligence (AI)-based control technique brings great potential for convenient aircraft operation. The key technology provides suggestions for flight management, making human pilots the center of the complex decision-making process.

Original research articles and reviews are welcome in this Special Issue. Research areas may include (but are not limited to) the following:

• Development of operational strategies for sustainable air transportation;
• Development of simulation models for UAM/AAM aircraft and systems;
• Development of energy management strategy and energy-optimal control methods for eVTOL agents driven by various types of energy supply units;
• Advanced and intelligent control law design facilitating future applications;
• Air traffic management strategy that maximizes the UAM/AAM system efficiency;
• Other innovative technologies and progress applied to UAM/AAM.

We look forward to receiving your contributions.

You may choose our Joint Special Issue in Aerospace.

Prof. Dr. Shu-Guang Zhang
Dr. Mingkai Wang
Guest Editors

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• green air mobility
• sustainable air transportation
• urban air traffic
• advanced air mobility
• electric propulsion
• vertical takeoff and landing
• sustainable energy