The solution focuses on two specific improvements during the flight planning phase:

• The better integration of letters of agreement (LoAs) between air traffic control (ATC) centres in the trajectory planned by the flight operations centre (FOC) and transmitted to the flight crew as part of the operational flight plan before take-off. This will allow the quality of the aircraft downlinked trajectory and its use by ATC in execution to be improved, thereby enhancing vertical flight efficiency.

• In the context of flight and flow information for a collaborative environment release 1 (FF-ICE/R1) next phase of implementation, the provision of preliminary flight plans by airspace users (AUs) ahead of dynamic network constraints publications initiated the day before operations. This will allow air traffic management (ATM) to better understand AU trajectory preferences and optimise constraints publication (e.g. route availability document (RAD)) to increase flight efficiency by minimising impact on preferred trajectories.