Modernization of the airline fleet avionics is essential to fully enable future technologies and procedures for increasing national airspace system capacity. However in the current national airspace system, system-wide benefits gained by avionics upgrade are not fully returned to aircraft/airlines that upgrade, resulting in a slow fleet modernization rate. Preferential merging is a best-equipped-best-served concept designed to incentivize avionics upgrade among airlines by allowing aircraft with new avionics (high-equipped) to be resequenced ahead of aircraft without the upgrades (low-equipped) at en-route merge waypoints. The goal of this study is to investigate the potential benefits gained by airlines under a high or low-equipped fleet scenario if preferential merging is implemented, using historical data for arrival flights into Phoenix Sky Harbor International Airport.

It is often the case that due to demand-capacity imbalance at an airport, flights are assigned by air traffic controllers an amount of delay that they must absorb before their expected arrival at the airport. This paper investigates the distance needed by aircraft to absorb such delays through a speed reduction of up to 10% with respect to their nominal speed. Thirty five representative days of operations with distinct traffic volume and delay characteristics are considered for the analysis. For each day, a simulation of traffic in the NAS is conducted in the absence of any constraints on sector or airport capacity thereby resulting in delay-free aircraft landing times. Flights are assigned delays due to demandcapacity imbalances at forty major US airports, which are computed through a first-comefirst-served scheduler. Distances from the airport where flights should reduce speed in order to absorb their assigned delay are computed through an aircraft trajectory generator. Analysis focuses on jet aircraft reaching their top-of-climb point at least 250 nautical miles from their destination airport. Out of all aircraft assigned delays, on average 73% were able to absorb that delay entirely through speed control. Of these aircraft, on average 93.5% of flights were able to absorb their assigned delay by reducing speed in either the same or an adjacent Air Route Traffic Control Center (ARTCC) from their arrival airport. ARTCCs that issue the highest number of advisories for speed reduction are Washington (ZDC), Atlanta (ZTL), and Chicago (ZAU). Finally, results are also provided for the specific cases of Las Vegas (LAS) and Phoenix (PHX) airports.

Preferential Merging is a best-equipped best-served air traffic management concept meant to accelerate the adoption of Automatic Dependent Surveillance-Broadcast Out (ADS-B Out) in the national airspace by giving an operational incentive to airlines who invest in upgrading their fleet. The concept relies on re-sequencing aircraft arrival order at en-route arrival merge-fixes favoring high-equipped aircraft (such as ADS-B Out) over lowequipped aircraft. This in turn reduces flight-time for high-equipped aircraft and moves them ahead in the arrival queue. In this study Preferential Merging was simulated using historical flight traffic into Phoenix Sky Harbor International Airport, focusing on a benefit analysis from an airline's perspective. A second set of Monte Carlo simulations randomizing aircraft equipage were run to determine the effectiveness of Preferential Merging as the percent of ADS-B Out equipped Aircraft increases. Results show that the policy creates a 4.5 minute reduction in total flight time for aircraft equipped with ADS-B Out, and that the incentive provided by the policy remains effective over a broad range of ratios of high-to low-equipage aircraft in the US airspace.

A goal of any precision departure concept, such as NASA Precision Departure Release Capability, is to improve throughput, efficiency and capacity by integrating departure, arrival and surface operations. This kind of concept is believed to have the potential of increasing flight efficiency and throughput by not missing assigned overhead-stream or arrival-stream slots. In the current Call For Release scheduling, a slot can be missed because of airport-departure delay, which is the sum of gate-departure delay, ramp delay, and taxi-out delay. This delay can be reduced by improved precision departure scheduling. The main thrust of the paper is to determine the delay-cost impact of Call For Release scheduling before gate-push-back and at gate-pushback. Seven different variations of scheduling algorithms were used in the simulation. Results reported in the paper considers 37,346 flights in the National Airspace System for one day in January 2011. Approximately 1,500 airports were included in the simulation. Results show that there is no significant benefit of scheduling before gate-push-back as opposed to at gate-push-back under assumed gate-departure and taxi-out time uncertainties, assuming a Call For Release is strategically done for all departures from all airports. However, if there were no gate-departure and taxi-out time uncertainty, which is unlikely in reality, the maximum benefit of scheduling an hour before gate-push-back is limited to 6.8% reduction in weighted delay (2*airborne delay + ground delay) compared to delay resulting from scheduling at gate-push-back.