Recently, autonomous aerial systems have received unparalleled popularity and applications as varied as they are innovative in the civil domain. The unmanned aerial vehicle (UAV) is now the subject of intensive research in both aeronautical and automotive engineering.

This paper presents a new, robust gain-scheduled adaptive control strategy for a class of UAV with linear parameter varying (LPV) models. The proposed controller synthesis involves a set of pre-tuned linear quadratic regulator (LQR) combined with fractional-order PID controllers supervised with an adaptive switching law. The main innovation in this work is the enhancement of the classical gain-scheduling adaptive control robustness for systems with LPV models by combining a set of robust LQR + fractional-order PID compensators. The stability of the resulting controller is demonstrated and its efficiency is validated using a numerical simulation example on a civilian UAV system airspeed and altitude control to illustrate its practical efficiency and achieved robustness.

Cellular structures provide lightweight, high-strength and excellent structural stability due to their repetitive modular unit design. By integrating cutting and folding Kirigami techniques with composite and plastic substrates, cellular configurations can significantly enhance the aero-mechanical performance of wing designs. This innovative structural technology shows great promise for unmanned aerial vehicles (UAVs), enabling flexible control and dynamic flight capabilities to meet varying operational conditions. This study presents an analysis and optimisation of the aeroelastic behaviour of cellular Kirigami wingbox (CKW) structures for multifunctional operations of micro-UAV wings to ensure stability and resilience in various dynamic flight conditions. The effect of thickness and internal cell angle of the cellular structure on static and dynamic aeroelastic behaviour is assessed through finite element analysis. By incorporating Bayesian optimisation, the multi-disciplinary design space of the cellular UAV wings has been efficiently explored to achieve optimal structural performance for adaptive UAV wings. The results show that Bayesian optimisation effectively identifies optimal design parameters for different multi-objective design weights, which improves the aeroelastic performance of the CKW structure.

Blade ice accumulation is a serious problem that changes turbine aerodynamics and dynamics, leading to lower power output and higher structural loading. Different from the literature, this paper investigates the performance effectiveness of baseline wind turbine controllers: the generator torque and collective blade pitch controllers against rotor blade ice accumulation. The NREL 5-MW turbine is utilised, and simulations of baseline controllers are conducted with the MS (Mustafa Sahin) Bladed Model for clean and iced blade cases. The performance of the controllers is examined in below (Region 2) and above (Region 3) rated regions under 1 m/s step rising wind speeds. Results are presented through various parameters, including turbine controllers’ gain(s), blade pitch angle, rotor speed, power, etc. Rotor speed response is used to evaluate the controllers’ performance. Even slight blade ice accumulation is estimated to affect turbine efficiency and characteristics, decreasing ${C_{pmax}}$ by 13.27%, slightly varying optimum blade pitch angle and tip speed ratio, altering the control input gain by up to 14.68%. Blade ice accumulation is observed to adversely affect baseline controllers’ performance. In Region 2, the torque controller exhibits reduced transient and steady-state performance, with rotor speed reaching the steady-state approximately 2 s later and showing a steady-state error of 1.86%. In Region 3, the pitch controller’s transient performance deteriorates at low wind speeds, particularly near the rated wind speed, leading to an increased decay time of up to 5.2 s. However, beyond 16 m/s, pitch controller performance gradually recovers, becoming nearly identical to the clean blade case at 21 m/s, while the controller steady-state performance remains unaffected.

This paper addresses the attitude control challenge of hypersonic morphing vehicles (HMVs) with uncertainties and actuator saturation. The primary contribution of this work lies in achieving a predefined settling time while ensuring robust control performance under morphing effects, actuator saturation and disturbances. Firstly, a control-oriented model is established based on the dynamics of HMVs. Subsequently, a nonsingular multivariable sliding mode manifold, utilising a switching function, is designed to attain predefined-time convergence and prevent singularity issues. A disturbance observer with an adaptive law is developed to precisely and swiftly estimate uncertainties and error states, while a predefined-time anti-saturation compensator is implemented to alleviate actuator saturation. Furthermore, closed-loop stability is guaranteed through rigorous Lyapunov synthesis. Extensive numerical simulations confirm the algorithm’s superiority in terms of control effectiveness.

The increase in activities related to unmanned aircraft systems and the implementation of this new ecosystem have introduced new hazards, impacting the operational safety of air traffic, particularly near airports, creating risks and disruptions in the flow of aircraft. The establishment of airspace for unmanned traffic management has required the integration of this new airspace with the existing one, bringing the potential for issues from this integration. A method was identified as needed to guide the detection of hazards posed to air traffic control activities and the consequent implementation of required mitigation measures. The aim of this work is to propose a framework for identifying hazards introduced to air traffic control, with a view to ensure the safe transition of this process. The method involved consulting air traffic operational safety specialists via a questionnaire, presenting the hazards highlighted in the literature concerning the integration of new airspace concepts within air traffic control activities. The results, obtained through a Delphi consultation, were analysed based on the most frequently assigned scores (mode) to reflect expert consensus. The results were organised into the proposed framework, establishing a guide to risk management activities aimed at implementing the change. The resulting structure was re-submitted to specialists and validated based on the Delphi method. Contributions to society include a guide for this process and potential future implementations, while the literature gap was addressed by adding knowledge to the scientific process.

This study proposes a geometric solution to the norm differential game design problem in target-attacker-defender (TAD) engagements, addressing key limitations of conventional zero-effort-miss approaches. By leveraging the geometric analogy between guidance-law-generated trajectories and Dubins paths, we reformulate the derivation of zero-effort-miss-based guidance laws as a Nash equilibrium optimisation problem, with optimal strategies determined through reachable set analysis of Dubins path frontier. The resulting model is a non-convex optimisation problem, which prevents the derivation of traditional state-feedback control laws. To overcome this limitation and enable real-time implementation, we develop a custom back propagation neural network, enhanced with a relaxation factor method for output filtering, a Holt linear trend model for outlier compensation and a saturation function for oscillation suppression. Extensive simulations demonstrate that the proposed framework significantly outperforms baseline methods. These results validate the effectiveness and robustness of our approach for high-performance TAD applications.

This review examines the critical role of meteorological data in optimising flight trajectories and enhancing operational efficiency in aviation. Weather conditions directly influence fuel consumption, delays and safety, making their integration into flight planning increasingly vital. Understanding these dynamics becomes essential for risk mitigation as climate change drives more frequent and severe weather events. Synthesising insights from 57 studies published between 2001 and 2024, this article highlights key variables – such as wind, temperature and convective weather – significantly impacting flight operations. A framework is proposed to improve air traffic management’s safety, efficiency and cost-effectiveness. The findings emphasise the need for systematically incorporating meteorological inputs into trajectory optimisation models, such as wind shear, convective storms and temperature gradients. This integration improves operational predictability and safety while advancing sustainability goals by reducing fuel consumption and CO2 emissions – an increasingly important priority amid rising climate variability and global air traffic demand.

The role of pylon-induced vortex structures on flame stabilisation within a supersonic pylon-cavity flameholder is numerically investigated. The study examines how the fuel jet interacts with the vortices produced by three distinct pylon-cavity flameholder geometries labelled as P0, P1 and P2. P0 represents the pyramidal-shaped baseline pylon configuration, whereas P1 and P2 consist of parallel and slanted grooves on the pylon slant surfaces with respect to the supersonic crossflow for the generation of instream vortices. The selection criteria for P1 and P2 are based on reduced effective blockage area compared with P0. The inlet flow Mach number used for the investigation is 2.2. A sonic ${{\rm{H}}_2}$ fuel injection at 2.5 bar and 250 K is used for all the test cases. Steady RANS reactive flow simulations are used for the assessments. An 18-step Jachimowski chemical kinetic scheme is used to model ${{\rm{H}}_2}$-air reaction mechanism. The flowfield structures within the pylon-cavity flameholder are categorised into two, (i) pylon-cavity geometry-induced vortex structures (II, III, and IV) and (ii) fuel jet vortex pairs (FJVP and SFJVP). The study shows that the interaction between these two decides the reactant mixture formation within the flameholder and the flame stabilisation. This study identifies four different flame-holding locations – L1, L2, L3, and L4 – and their strength depends on the pylon configuration. Overall the P2 configuration is found to perform better than the others in terms of high heat release magnitude and flame spread within the combustor.

In this paper, a sliding mode guidance law for impact angle control without violating a seeker’s field-of-view limits is proposed against targets with various motions and unknown acceleration, including stationary, constant-velocity moving and manoeuvring targets. To develop the guidance law, the kinematic conditions for engagement geometry are defined, and the sliding mode control is applied to satisfy the homing constraint and impact angle control. Then, the relation between look angle, the desired line-of-sight angle and desired impact angle is established to guarantee the target in the field of the missile’s view. The stability of the proposed approach is analysed using Lyapunov theory. Furthermore, the look angle is examined to verify the field-of-view constraint, and a capturability analysis is conducted. To evaluate the performance of the proposed law, numerical simulations demonstrate that the proposed approach achieves satisfactory miss distance and impact angle error while adhering to the field-of-view limit.

Electrical contacts are critical components in all connector systems, as they enable the flow of electrical current. However, power contacts are increasingly subjected to various forms of degradation due to the high input power demands of modern electrical circuits. One of the primary causes of damage is the electrical arc, which can lead to erosion and oxidation of contact surfaces, ultimately resulting in electrical insulation failure. In industries such as aerospace, this type of failure can be mission-critical, especially in scenarios where in-orbit repair is not possible. Therefore, the design and choice of contact material must be carefully considered. Based on theoretical studies of arc-related phenomena, we conducted experimental tests focusing on the optimisation of hemispherical contact using samples made from various pure and coated materials. The contact surfaces in these tests were composed of high-conductivity base such as copper (Cu) and aluminum (Al), and were also coated with noble metals such as gold (Au) and silver (Ag). These materials are commonly used in sectors including aerospace, automotive and general industrial applications. To ensure a fair comparison, all contact samples were manipulated and tested under consistent conditions that reflect their real-world operational environments. The resulting arc parameters were identified and analysed through modeling to determine the most suitable contact design and material most capable of withstanding arc-related degradation over the mission duration, thus ensuring longer service life in applications were a continuous monitoring and repair are not feasible. The results show that repetitive exposure to high input power significantly damages contacts surfaces. Furthermore, the use of coated materials effectively extends the lifespan of the electrical contacts. Scanning electron microscope (SEM) and energy-dispersive X-ray spectroscopy (EDX) analyses support these findings, revealing that high-power input increases erosion rates and leaves pronounced marks on the contact surfaces.