Advanced Pilot-in-the-Loop Control System for Aircraft Ground Handling

The high-speed regime in the aircraft rollout phase during landings is a critical stage where longitudinal and lateral stability must be maintained. In the longitudinal direction, various high-performing antiskid (AS) algorithms have been developed, aiding the pilot in minimizing the braking distance and preventing wheel locking. Instead, the lateral stability problem, which can produce runway excursions, has received considerably less attention. The presence of asymmetries, such as crosswind, runway grip variability, or failure conditions, can make the task of maintaining directional control difficult for the pilot. In this article, we propose and evaluate a modular architecture for a control system that acts as a pilot lateral assistant during ground handling maneuvers. The lateral assistant simultaneously uses commonly employed ground handling actuators to correct incipient lateral instabilities. The proposed architecture seamlessly interacts with the AS system and copes with various types of actuator failures, including the often neglected free caster dynamics from a nose wheel steering failure. The control system is evaluated in a pilot-in-the-loop simulation that accurately represents the relevant ground handling dynamics, validated using experimental data. We show that our system effectively improves directional control in various scenarios, including actuator failures and environmental disturbances that strongly excite the lateral dynamics.