Aircraft emissions currently account for 2-3% of total global emissions and are projected to increase further. Public pressure is amounting for airlines to pay for emissions, which would increase airline expenses and air travel costs1. In general, Environmentally Responsible Aviation (ERA) research seeks to develop ways to mitigate the adverse impacts of aviation on the environment2, which include fuel burn, emissions and noise.

Intuitively, adverse environmental impacts of aviation may be reduced through improvement in three areas or their combinations: vehicle design3, traffic management4, and individual aircraft trajectories. While innovative vehicle design may be critical for making fundamental progress in ERA, its benefits can only be achieved in the long term. In comparison, effective trajectory design not only provides the most efficient near-term solutions, it also provides insights into both vehicle design and traffic management. In the past, effective departure and approach procedures have been studied for noise abatement5, 6. Optimization methods are also used to design departure and approach trajectories for noise abatement7-9. Recently, Torres & Chaptal study the reduction of aircraft emissions and noise during the climb phase by optimizing departure procedures10, using operational flight path software and a multi-mesh adaptive direct search method.