Linear holding for airspace flow programs: a case study on delay absorption and recovery

Abstract

This paper presents a method to introduce linear holding to flights affected by Airspace Flow Program (AFP) initiatives. Trajectories are optimized at their planning stage in such a way that the program performance is improved in terms of delay absorption before the congested area, and delay recovery at the destination airport. This recovery process is studied by comparing the case where the same fuel consumption is fixed as the nominal flight, with several cases where some extra fuel allowances are considered at the flight planning stage. The effects for AFP delayed flights are thoroughly discussed in a case study followed by a sensitivity analysis on possible influential factors. Results suggest that using the proposed method could partially recover part of the AFP delay, even with no extra fuel allowances (e.g., reducing 3.3 min of ground delay and 1.7 min of arrival delay for a typical short-haul flight). When extra fuel is allowed, however, the maximum delay recovery increases up to 10 min for the studied case, which also proves to be more cost-efficient than current operations, when flight speed is increased after experiencing all delay on ground