Key points are not available for this paper at this time.
The problem of navigating an aircraft over and through terrain is an important problem in trajectory planning. Typically, only two-dimensional motion of the aircraft (longitudinal aircraft control) is considered for such problems despite the fact that better terrain following may be achieved by following a three-dimensional trajectory. Furthermore, in collision avoidance maneuvers, pulling the aircraft up is not always the optimal method for avoiding terrain and climbing turns or lateral maneuvers must sometimes be considered. It is well recognized that terrain-following trajectories are important for many military aircraft in defense applications.
Paul Williams (Thu,) studied this question.