Wake vortex and downwash modelling for a quad-plane air mobility vehicle

• Wake Vortex and Downwash Modelling for a Quad-plane Air Mobility Vehicle • Introduces a hybrid wake-vortex model suitable for quad-plane aircraft configurations. • Presents an analytical framework to generate directionally inflated avoidance volumes. • Introduces proximity and superposition effects to model worst-case turbulence scenarios. • Simulates vertical/lateral safe separation with various aircraft size and flight conditions. • Supports the development of air traffic management tools for advanced air mobility. Quad-planes have received growing attention in the aerospace sector due to their versatility, operational efficiency, and potential contributions to sustainable aviation. To fully realize the potential benefits offered by this aircraft configuration, ongoing research aims to enable the seamless integration of highly automated and autonomous VTOL/hybrid aircraft configurations into unsegregated airspace. This integration necessitates the development of a Separation Assurance and Collision Avoidance (SACA) system that accounts not only for the performance of Communications, Navigation, and Surveillance (CNS) systems and onboard avionics but also for external environmental disturbances. Among these, wake turbulence represents a critical factor that may adversely impact the stability and control of AAM vehicles. This paper introduces a novel methodology for modeling wake turbulence encountered by quad-planes operating in complex and dynamic airspace environments. It incorporates this model into a unified analytical framework for SACA. The framework accounts for uncertainties in CNS performance to generate avoidance volumes required for effective conflict detection and resolution. Furthermore, it integrates advanced wake turbulence modeling with real-time data processing algorithms to detect, assess, and respond to turbulence generated by nearby aircraft. By embedding these elements within a unified analytical structure that supports real-time path planning and obstacle avoidance, the proposed framework enhances the operational safety of uncrewed aircraft in congested airspaces. The presented model offers a robust solution for integrating wake turbulence effects into SACA systems, thereby mitigating the risk of turbulence-induced flight upsets and collisions, especially in high-density and low-altitude operations, such as in Urban/Regional Air Mobility (UAM/RAM). This framework provides a foundational tool for advancing AAM safety and contributes to the broader objective of safely incorporating quad-planes and other hybrid VTOL/airplane configurations into unsegregated civil and military aviation environments.