With the advent of commercial transportation in Urban Air Mobility (UAM), the concept of Simplified Vehicle Operations (SVO) has been integrated into aircraft design, aiming to streamline operational procedures to meet future transport demands. However, there is uncertainty regarding whether electric Vertical Take-Off and Landing (eVTOL) aircraft, which are designed based on SVO, meet airworthiness criteria and whether their control interfaces adhere to ergonomic standards for user-friendliness. To address this issue, an experiment on Mission Task Elements (MTE) was conducted to assess the handling qualities of SVO-based eVTOL aircraft. 20 participants were recruited for the experiment, during which their subjective ratings of handling qualities using Cooper-Harper Rating Scale, qualitative comments through semi-structured interviews, and electromyography (EMG) data and eye-tracking data were recorded. Additionally, a handling qualities assessment model based on Gramian Angular Field (GAF) and 2D-Convolutional Neural Networks (2D-CNN) was proposed. The results indicate that poor control interface design significantly affected the participants' EMG and eye-tracking signals. Benefiting from the spatio-temporal information provided by GAF images, the proposed 2D-CNN achieved an accuracy of 93.6% in predicting eVTOL handing qualities levels. This study provides a new perspective for the objective assessment of eVTOL handling qualities and offers significant guidance for the future design of SVO.

Horizontal takeoff and landing vehicles with integrated aero engines, blended wing bodies, and combined cycle power have the potential to be swiftly deployed and utilized in repeated aerospace round-trip missions with great transportation efficiency. However, their flight dynamics are affected by strong nonlinearity, aero-engine-elastic coupling, longitudinal-lateral kinematic coupling, and flight attitude-trajectory coupling, making control design challenging. In this regard, a flight dynamics model is established in this paper, which describes various coupling characteristics of a general blended-wing-body combined-cycle-power vehicle. Then, its flight dynamic characteristics are analyzed. By combining traditional PID control with dynamic inversion to suppress couplings, a multi-loop control law that is simple to apply is created. The multiple stochastic simulation results show that the control law not only helps suppress couplings but also achieves good tracking performance in attitude and trajectory, as well as good control robustness and anti-interference ability under uncertainties such as modeling, environment, and sensing.

The human factors and their interaction with other factors play an important role in the flight safety of transport aircraft. In this paper, a paradigm of risk assessment for transport aircraft interacting with piloting behaviors is proposed, with focus on landing which is the most accident-prone flight stage in aviation safety statistics. Model-based flight simulation serves as our data source for landing risk analysis under uncertainties. A digital pilot in the loop that reflects the human piloting behaviors is employed to facilitate simulation efficiency. Eight types of unsafe events in landing are identified from statistics. On this basis, the landing safety boundary is extracted via stochastic simulation to divide safety and hazardous flight status domains, which contributes to flight status management and risk warning. The simulation results indicate that appropriate piloting behavior, which is active response and fast target acquisition with minimum overshoot and fluctuation, shows benefit to landing safety. The subset simulation technique is employed to further refine the boundary with less computational workload. Furthermore, the effect of airspeed, windspeed, and other factors on landing risk is also discussed. The proposed risk assessment method would help optimize operation procedure and develop targeted pilot training program.

To predict and regulate the space vehicle’s undesirable coupling motion produced by tiny amplitude sloshing of liquid propellant, a transfer function model identification study is carried out based on the findings of numerical calculations. For an example of a horizontally placed kerosene tank in a vehicle, during the level flight in the re-entry phase, a force effect transfer function description model is established with the range of rotational motion of interest, based on which a sloshing suppression design is carried out to increase sloshing damping and weaken the impact of sloshing on flight. The findings show that the transfer function can capture the impacts of the liquid propellant sloshing force, which can be utilized to anticipate space vehicle flight characteristics and design sloshing suppression.