Enabling Trajectory Based Operations through Air-Ground Data Exchange

Abstract

Trajectory Based Operations (TBO), a key concept in the US Next Generation Air Transportation System (NextGen) and in Europe’s Single European Sky ATM Research (SESAR), allows for more efficient planning and execution of flight plans. The basis for TBO is to plan and perform operations using a shared view of the flight that takes into account user preferences and is expressed by a four-dimensional (4D) trajectory. Interoperability issues, due to dissimilar requirements that trajectories need to satisfy in the various automation systems involved in air traffic management, could limit the efficiency gains expected from TBO. Recognizing the importance to TBO of advancing trajectory synchronization and negotiation technologies, Lockheed Martin, GE Aviation Systems and GE Global Research have joined forces to develop and test trajectory synchronization strategies. We identified the steps and specific messages that need to be exchanged in order to resolve discrepancies between the trajectory used by the Flight Management System (FMS) to guide the aircraft and the trajectory used by Air Traffic Control (ATC) ground automation systems. Using real world FMS and ATC systems we developed trajectory synchronization and negotiation algorithms and methods to integrate the FMS trajectory directly into the ground automation systems used by ATC. The FMS trajectory takes into account operator preferences and has the benefit of the high fidelity aircraft performance models and flight specific parameters that affect the trajectory. In the process of synchronizing the air-ground trajectories, all the advantages of the FMS trajectory are now available to ground automation.