Analysis of Energy-Optimal Aircraft Landing Operation Trajectories

Abstract

This paper presents a method for the energy-optimal operation of a fixed-wing aircraft tracking a prescribed landing path in the three-dimensional space with a fixed time of arrival. The problem is converted to an optimal control problem with one state variable, which is subject to state and control input constraints along the path. It is shown that the solution to this energy-optimal tracking problem provides a good approximation to the minimum-fuel problem. The switching structure of the optimal solution is analyzed, and a semi-analytical method is proposed for computing the optimal solution. Compared to standard numerical optimization methods the proposed method is guaranteed to converge to the optimal solution, and it is computationally much more efficient. Numerical examples are presented to demonstrate the validity of the proposed approach. As verified by these numerical results the proposed energy-optimal solution can help improve aircraft fuel efficiency during the landing phase.