Simulation of airborne ATFM delay and delay recovery by cruise speed reduction

Air Traffic Flow Management (ATFM) regulations, such as ground holdings, are often cancelled before their initially planned ending time. This early cancellation leads to an unnecessary ground delay and a misuse of airport or airspace resources. In previous publications, the authors have suggested a speed reduction strategy aiming at splitting the assigned ATFM delay between ground delay and airborne delay. If the aircraft flies at the minimum speed that gives the same fuel consumption as initially planned, the airline can maximise the airborne delay without any extra fuel consumption. If the regulation is cancelled before it was initially planned, the aircraft already airborne will be in a better position to recover part of the delay without incurring in additional fuel costs. In this paper, this speed reduction strategy has been simulated with the FACET tool for a whole day of flights inbound San Francisco airport (California). For each flight in the data set, it has been computed the maximum amount of airborne delay that can be performed. Moreover, the amount of delay that can be recovered has been also computed as a function of the time the regulation is cancelled. Preliminary results show, at first glance, a linear relationship between this cancellation time and the delay recovery which encourages as future work, to develop a parametric model of this delay recovery.