Free Maneuvering, Trajectory Negotiation, and Self-spacing Concepts in Distributed Air-ground Traffic Management

Simulation research on three DAG-TM CEs— CE 5: En Route Free Maneuvering, CE 6: En Route Trajectory Negotiation, and CE 11: Terminal Arrival Self-Spacing—began in 2001 at the NASA Ames, Glenn, and Langley Research Centers [3-5]. It will continue through 2004, with regular simulation evaluations of the developing concepts, tools and procedures. Related prior research is presented in [59]. This paper describes a simulation conducted at NASA Ames in September 2002 to explore the potential benefits and viability of our current implementation of the three CEs. A related paper describes the potential benefits of trajectory-oriented time-based arrival operations implemented to support the three CEs in this simulation [10]. Planned future simulations will address severe weather, special use airspace, and an increased number of aircraft equipped with cockpit display of traffic information (CDTI). Joint simulations with NASA Langley and NASA Ames will begin in 2003. A simulation of integrated air and ground operations was conducted at NASA Ames Research Center to evaluate three Distributed Air/Ground Traffic Management (DAG-TM) Concept Elements – En Route Free Maneuvering (CE 5), En Route Trajectory Negotiation (CE 6), and Terminal Arrival Self-Spacing (CE 11). Controller participants managed simulated traffic using Center Terminal Radar Control (TRACON) Automation System tools [1] while commercial pilot participants flew aircraft simulators equipped with a cockpit display of traffic information (CDTI) that had conflict detection and resolution and required time of arrival capabilities. Data were collected from twelve simulation runs to compare our current implementation of DAG-TM en route and terminal concepts against baseline conditions that approximated current day operations. Results suggested that potential improvements in efficiency and capacity may be gained without compromising safety or significantly increasing workload in the two en route conditions. CE 6 – En Route Trajectory Negotiation The goal of CE 6 is an en route operational environment that supports enhanced trajectory coordination between controllers and pilots of properly equipped aircraft. Automated data link functions communicate winds, traffic flow management (TFM) constraints, and current aircraft state information between air and ground. Pilots and controllers use decision support tools (DSTs) that process this information to develop conflict-free, TFM-compliant flight path changes, which are sent as trajectory change requests (pilot to controller) or trajectory clearances (controller to pilot) using controller-pilot data link (CPDLC). While flight path changes can be proposed by either party, responsibility for maintaining separation in the CE 6 environment lies exclusively with the controller. DAG-TM research is funded by Airspace Systems program as part of the Advanced Air Transportation Technologies project. DAG-TM activities are conducted by NASA Ames, NASA Langley, and NASA Glen Research Centers.