Operational Evaluation of the Direct-To Controller Tool

Direct-To is a decision support tool for en route radar controllers that provides clearance advisories for windfavorable direct routes and information on potential traffic conflicts. Direct-To includes a highly automated “what-if” trial planning function that allows controllers to quickly visualize, evaluate, and input flight plan amendments for route and altitude changes. Direct-To continuously analyzes all aircraft for wind-favorable direct routing opportunities and for traffic conflicts. “Direct-To” route advisories and conflict information are displayed in the flight data block and in optional lists on the controller’s traffic display. A mouse (or track-ball, hereafter referred to as “mouse”) click on a conflict advisory, either in the flight data block or the Conflict List, toggles a graphic display of conflict information. A mouse click on the data block activates the trial planning function which shows a graphic display of the trial route, and analyzes the route for traffic conflicts, preferential routing restrictions, and flying time. The trial planner allows the controller to quickly select a different fix and/or add an auxiliary waypoint, by a point and click action. A final mouse click sends the flight plan amendment to the Host computer. An operational evaluation of the Direct-To Tool was conducted at Fort Worth Center from May 21 – June 14, 2001. Direct-To functionality was implemented by connecting one additional software module to the daily use CTAS Traffic Management Advisor system at Fort Worth Center. The user interface was deployed on flat panel auxiliary displays at 3 high altitude sectors. Over a four week period controllers activated 3204 trial plans and sent 1198 Direct-To flight plan amendments to the Center Host computer during 136 sector-hours of operation. On average, one trial plan was created every 2.5 minutes, and one Direct-To Host amendment sent every 7 minutes. Controller feedback on the Direct-To Tool was consistently very positive and the controller team felt that all Direct-To functionality would be beneficial if integrated into their R-Side traffic situation displays. Controllers used Direct-To during a wide variety of traffic conditions including very busy (Monitor Alert) periods. During severe weather periods, Direct-To identified aircraft on obsolete weather avoidance routes resulting in an average savings of 9.4 minutes per flight. A methodology is presented to estimate the net flying time savings that could be achieved with DirectTo aiding compared to baseline (no tool) operations. Test data show a net savings of about 1 minute for some flights and suggest a net operational savings of 900 flying minutes per day or $9,000,000 per year.