Geometrical Vertical Trajectory Optimization - Comparative Performance Evaluation of Phase versus Phase and Altitude-Dependent Preferred Gradient Selection

This paper presents a comparative analysis of the results of two vertical flight trajectory optimization strategies, obtained using a new geometrical trajectory optimization algorithm developed at the Laboratory of Applied Research in Active Controls, Avionics and AeroServoElasticity LARCASE. The first strategy geometrically constructs the vertical flight trajectory as function of the along-the-track distance and altitude constraints associated with each way point in the flight plan, and a preferred gradient value described as a function of the flight phase and altitude. The second strategy employs a preferred gradient value dependent only on the flight phase. The optimization criterion is represented by the minimization of the total number of climb, horizontal, and descent trajectory segments. The comparison of the optimized trajectories generated using the two strategies are performed relative to the number of trajectory segments and their gradient values. The novelty and the advantage of the presented algorithm is the fact that it allows the construction of an optimal vertical flight trajectory without performing time and resources-intensive computations employing an aircraft performance model.