Value of Extended Time-Based Metering for Optimized Profile Descent–Based Arrival Operations

Abstract

As one of the key components of the implementation plan for the Next-Generation Air Transportation System, time-based metering delivers a more precise trajectory and has been shown to be more efficient than distance-based metering. In addition, by adding metering points upstream in en route space, extended time-based metering can help reduce flight trajectory deviations at metering points. With these advanced metering procedures, a well-designed metering configuration can improve the efficiency of arrival operations such as optimized profile descent (OPD). This paper aims to identify the optimal metering point configurations for OPD operations at airports on the basis of an extended time-based metering concept, as well as the value of such metering in OPD. To this end, the paper adapts a two-phase algorithmic framework to identify the number and locations of metering points under the extended time-based metering setup. Extensive numerical simulations based on OPD implementations at Atlanta (Georgia) International Airport are performed for different extended metering ranges and average arrival rates. Optimal time-based metering configurations are obtained for different extended metering ranges, and corresponding savings are provided. Marginal savings from additional metering ranges are shown to be decreasing, and it may not be value-adding to increase the extended ranges above a certain level. The results are further generalized to the top 10 major airports in the United States, and estimated savings attributable to optimization of extended time-based metering points are calculated to be around $33.4 million, an additional 14% improvement on fuel efficiency over current OPD operations. In addition, the value from usage of extended time-based metering is shown to be around $4.2 million for the top 10 major airports compared with the use of distance-based metering methods.