Stall Recovery Method With Optimal Control for T-Tail Transport Aircraft and Evaluation in Monte Carlo Simulation

T-tail transport aircraft has stable steady states at high angles of attack in its equation of motion due to deep stall, which complicates stall recovery. Although procedures for recovering from the steady states have advanced in recent years, practical applications require strategies that address a wide range of initial conditions. In this study, first, an optimal control problem is solved to reduce the angle of attack from a representative stalled state. Then, an algorithm is proposed to guide recovery from various stalled initial states to the steady level flight via the representative state. The optimal input leverages the coupling between longitudinal and lateral dynamics to transition state variables across the boundary of attraction in the nonlinear dynamical system. Monte Carlo simulations were used to evaluate the algorithm, demonstrating successful recovery in almost all cases from a wide range of phase space.