This paper describes an aircraft trajectory optimisation algorithm that is part of the time and energy managed operations (TEMO) concept, a new trajectory planning and guidance strategy for advanced four dimensional (4D) continuous decent operations. In TEMO, a trajectory is planned in such a way that the best vertical trajectory profile is computed (according to a given optimisation objective), while satisfying at the same time air traffic control required times or arrival (RTA) at one or more waypoints. The guidance part of TEMO is mainly based on a speed-on-elevator law, where the calibrated speed plan is followed. TEMO was evaluated in a highly realistic environment with qualified pilots using the Generic Research Aircraft Cockpit Environment (GRACE), at the National Aerospace Laboratory of The Netherlands (NLR). Results show that the TEMO algorithm largely meets time accuracy requirements at the initial approach fix, while further work is needed to achieve the very demanding accuracies imposed at the runway threshold.

Peer Reviewed