Linear Holding for Reducing Additional Delays Experienced by Flights Subject to Ground Holding at no Extra Fuel Cost

Abstract

This paper presents a method to implement linear holding (LH) for flights subject to ground holding in context of the upcoming Trajectory Based Operations in air transportation, aimed at reducing additional delays raised from the lack of coordination between various traffic management initiatives (TMIs) without incurring extra fuel consumption. Firstly, motivated from previous works on the features of LH to absorb delays airborne, a potential applicability of LH to compensate part of the fixed ground holding is proposed. Then, the dynamic adjustment of LH in response to TMIs associated tactical delays is formulated as a multi-stage aircraft trajectory optimization problem, addressing both pre- and post-departure additional delays. Finally, the effects of performing LH are investigated for a particular flight, discussing the changes of vertical trajectory, speed profile, fuel consumption and flight timeline, for each step of optimization. Results suggest that additional delays of 25mins in a typical case study can be totally recovered at no extra fuel cost. A notable extent of delay reduction observed from the simulation assessment further supports the benefits of LH for reducing different combinations of additional delays.