This paper presents a novel active gust load alleviation approach within a multi-objective flight control framework developed by NASA for a flexible wing aircraft. The aircraft model is based on the NASA Generic Transport Model (GTM). The wing structures incorporate an aerodynamic control surface known as the Variable Camber Continuous Trailing Edge Flap (VCCTEF). Previous work already showed the ability of the VCCTEF to perform aeroelastic mode suppression, drag minimization and maneuver load alleviation in a multi-objective flight control framework. In this paper, the multi-objective flight control framework is extended to include active gust load alleviation. A Linear-Quadratic Gaussian (LQG) controller is augmented with Model Reference Adaptive Control (MRAC) to provide active gust load alleviation. Disturbance estimation is done using an Extended State Observer (ESO) to support the design of the active gust load alleviation controller. The results demonstrate the potential of active gust load alleviation within a multi-objective flight control framework for a high-aspect ratio flexible wing aircraft embodied with the VCCTEF.

This paper contains a simulation study of a real-time adaptive least-squares drag minimization algorithm for an aeroelastic model of a flexible wing aircraft. The aircraft model is based on the NASA Generic Transport Model (GTM). The wing structures incorporate a novel aerodynamic control surface known as the Variable Camber Continuous Trailing Edge Flap (VCCTEF). The drag minimization algorithm uses the Newton-Raphson method to find the optimal VCCTEF deflections for minimum drag in the context of an altitude-hold flight control mode at cruise conditions. The aerodynamic coefficient parameters used in this optimization method are identified in real-time using Recursive Least Squares (RLS). The results demonstrate the potential of the VCCTEF to improve aerodynamic efficiency for drag minimization for transport aircraft.