Modeling of Traffic Management Advisor as a Baseline for the Assessment of Metroplex Time-based Scheduling Concepts

When assessing NextGen metroplex time-based scheduling concepts there is a need for a current-day baseline to compare their performance against. In the current air traffic system, the Traffic Management Advisor (TMA) is a decision support tool (DST) that assists the Center Traffic Management Coordinators (TMCs) and controllers with planning and time- based scheduling of arrival traffic. TMA is a part of a suite of DSTs developed by the National Aeronautics and Space Administration (NASA) called the Center-TRACON Automation System (CTAS). TMA is currently installed and functional at all 20 Air Route Traffic Control Centers (ARTCCs) in the U.S. TMA's time-based scheduling engine, called the Dynamic Planner (DP), is the current state-of-the-art in multi-airport time-based arrival scheduling controller aids. TMA's DP can handle up to five different airports within a TRACON and treats them as separate entities from the scheduling perspective. This paper discusses the development of a proxy model of TMA's DP scheduling capability and its application to the assessment of one NextGen scheduling capability as applied to a set of generic metroplex geometries. A validation study was conducted using an in-house CTAS simulation capability to assess how closely it emulates the real TMA schedules. Results of this validation study are also presented. This research work, which started as a small component within a larger metroplex scheduling evaluation framework, eventually produced some valuable insights related to implications for TMA arrival scheduling as applied to metroplex operations - in a metroplex environment, TMA's delay rippling effect tends to starve the metroplex runways if the arrival flows are not segregated at the TRACON boundary (i.e., if they have to use commonly-shared arrival-fixes). Also, relaxing (i.e., increasing) TMA's terminal delay absorption limit leads to lesser runway starvation, but at the same time it allows for higher terminal delays. More research is needed to find the "sweet-spot" AMDT value which minimizes the runway starvation without increasing the TRACON delays beyond manageable levels. Further research in this direction is expected to provide useful information for supporting future NextGen metroplex arrival scheduling algorithm and Area Navigation (RNAV)/Required Navigation Performance (RNP) terminal route design and development.