Effects of linear holding for reducing additional flight delays without extra fuel consumption

This paper presents an approach to implement linear holding (LH) for flights initially subject to ground holding, in the context of Trajectory Based Operations. The aim is to neutralize additional delays raised from the lack of coordination between various traffic management initiatives (TMIs) and 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. Results suggest that additional delays of 25 mins in a typical case study can be totally recovered at no extra fuel cost. A notable extent of delay reduction observed from the computational experiments further supports the benefits of LH for reducing different combinations of additional delays without consuming extra fuel.