Refined Benefits Assessment of Multi-Center Traffic Management Advisor for Philadelphia and New York

This paper presents a refined benefit assessment of applying the Traffic Management Advisor Multi-Center (TMA-MC) to meter the arrival flows into the Philadelphia Terminal Radar Approach Control (TRACON) (PHL) and the New York TRACON (N90) when predicted demand exceeds predicted capacity. TMA-MC extends the time based metering algorithms of TMA, which are designed for metering within a single center, to be applied for arrival flows that require multiple centers for time based metering to be effective. The primary functions of TMA-MC were identified through a functional analysis, and a number of benefit mechanisms were identified by applying the TMA-MC functions to alleviate constraints in current distance based metering operations. Then each TMA-MC function was modeled and simulated in detail, ensuring that the most important benefit mechanisms were captured. The analysis in this paper improved on previous attempts to assess the TMA- MC benefits at PHL and N90 through a number of enhancements: First, by computing the benefits of TMA-MC time based metering with respect to simulated baseline delays as opposed to actual baseline delays, only those sources of delay that TMA-MC is likely to mitigate were accounted for. Current operations using distance based metering were modeled and simulated to provide the baseline. Second, demand which was modeled through detailed flow networks and statistical unimpeded travel times between fixes to generate undelayed estimated times of arrival at airports and fixes, was improved by incorporating wind data. Third, capacity modeling was improved by making the arrival acceptance rate a function of the departure rate. Finally, assumptions concerning how TMA-MC will be operated were refined, most importantly with regard to the periods of time based metering application when demand is predicted to exceed capacity and with respect to the assumed airport arrival rate capacity constraints imposed by TMA-MC. These enhancements rendered the estimated benefits more accurate, more realistic, and more conservative. By comparing the simulated baseline delays to the simulated delays under TMA-MC, the benefits of TMA-MC were quantified in terms of increased throughput, reduced delay, and reduced fuel consumption, for 15 days in November 2003. Each of these benefits was converted into economic terms, and the combined results extrapolated to yearly results. Yearly benefits due to the implementation of TMA-MC are presented both assuming an increased airport arrival rate capacity resulting from TMA-MC operation, and more conservatively, assuming no increase in arrival rate capacity over current operations. The sensitivity of the results to a number of variables, such as arrival rate capacity, sector delay absorption capability, error in meeting scheduled times of arrival, and duration of metering periods, is also presented.