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.

The effects of flap extension time on the fuel burn of commercial aircraft

“…However, this procedure may introduce an earlier deceleration in which an aircraft is able to use high-lift devices, such as flaps and spoilers, which increase the drag of the aircraft and lead to an increase in engine thrust and hence result in higher fuel consumption in the approach phase. This can be avoided by applying different optimized profile descent (OPD) procedures which aim to minimize fuel burn (FB), emissions and noise impacts (Chen and Solak, 2015; Chen and Solak, 2016; Kuenz et al , 2007; Thomas and Hansman, 2019; Albarran et al , 2018; Kendall and Clarke, 2018) by maintaining the trajectory of the aircraft as close as possible to the optimal vertical and speed profiles during climb, approach and landing. For instance, continuous descent approaches (CDAs) (Clarke et al , 2004; Errico and Vito, 2017; Oliveira and Büskens, 2012; Sahin et al , 2018; Jin et al , 2013; Cao et al , 2014; Dalmau and Prats, 2017) which allow aircraft to remain at higher altitudes for longer at idle or near idle thrust until reaching the runway, and also delayed deceleration approaches (DDAs) (Sandberg et al , 2016; Evans, 2016; Reynolds, 2014; Rodriguez et al , 2013), which permit aircraft to maintain higher speed for longer during the initial stages of the approach are considered to be OPD procedures.…”