Design of a Center of Gravity Control Law with Unbalanced Fuel in Aircraft Wing Tanks

Aircraft center of gravity (CG) control is important for effectively reducing trim drag and offering potential economic performance benefits. CG control is based on the fuel transfer system, which enables fuel to be transferred among various fuel tanks during flight. However, the fuel consumption of aircraft in flight may lead to the problem of unbalanced amounts of remaining fuel in the wing tanks. Aiming at this problem, this paper proposes a CG control strategy to cope with possible imbalances in fuel in aircraft wing tanks. First, a detailed description of the typical fuel system is presented. Then, the overall structure of the fuel transfer-based CG control system is given, and an aircraft CG control algorithm under the condition of unbalanced fuel in the wing tanks is proposed. Finally, simulations are carried out for the case of unbalanced fuel in the two wing tanks, and the results demonstrate the effectiveness of the proposed algorithm.