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PJ.18 W2 4D skyways


The project ‘4D skyways’ covers the following candidate SESAR Solutions:

  • Solution PJ.18-W2-53 Improved Ground Trajectory Predictions enabling future automation tools.

The solution focuses on the operational validation of improved CD&R tools. The main goal is to increase the quality of separation management services reducing controller workload and separation buffers and facilitating new controller team organisations. The foundation is the improvement of the ground TP(EPP data beyond weight and CAS, known MET data or new MET data and capabilities, etc.).

  • Solution PJ.18-W2-56 Improved vertical profiles through enhanced vertical clearances.

The objective of this solution is to develop an automation support for ATCOs to issue vertical constraints that support more efficient flight profiles while ensuring separation provision. First step, for flight still in climb, enhanced prediction of vertical profile data are presented to ATCOs to facilitate decision making. In a second more advanced step, the ATC system would generate proposals for conflict-free clearances that take anticipated aircraft performance into account, which can be uplinked to the flight crew by ATCO..

  • Solution PJ.18-W2-57 RBT revision supported by datalink and increased automation.

The solution aims at supporting a continuous increase in the amount and the usefulness of information shared between air and ground and of the level of automation support to controllers and pilots, e.g. towards the automatic uplink of clearances with or without previous controller validation and towards increased use of the auto-load to FMS of uplinked clearances and of managed/automatic mode by the flight crew.

  • Solution PJ.18-W2-88 Trajectory Prediction Service.

This solution is a technical service conceived as being provided to Europeans ANSPs, AUs, AO, Military and the Network Manager (NM) in support of trajectory operations. The solution is intended to provide a single point of truth for a specific trajectory in the time frame from creation in long term pre-flight planning through to the flight execution phase. The solution is not intended to replace today’s flight data processing systems and consequently the service can be used as an input to ATC systems but not used directly for control purposes.

The SESAR concept is based upon the fundamental element of trajectory sharing. The ultimate goal is a trajectory based ATM system where actors optimise business and mission trajectories through common trajectory information taking into account users priorities and ATC constraints. The objective is the sharing of the trajectories between the ATM actors including airspace users through an iterative process to take into account more accurate data once available (e.g. intentions, MET forecast, current traffic, airspace management). This will allow the Airspace User to choose the preferred way of integrating ATM constraints when required. There is a need to agree in more details on the elements that will constitute the reference business trajectory (RBT) in trajectory based operations (TBO) and better understand how these will be used operationally. The new ATM Solutions will need better trajectory predictions and additional data exchanges between systems.

A generic principle of the SES and the SESAR programme is that, where services can be delivered in a harmonised manner, they should be done so. The future high level architecture should offer an option for the de-fragmentation of the ATM system through the provision of harmonised or Common Services (a service to consumers that provides a capability in the same form that they would otherwise provide themselves). Introducing a Common Service will change how a solution is delivered and this is likely to change organisational relationships between the stakeholders due to the provision and consumption of the new service.

The project will contribute to increase:

  • Safety by generating and proposing conflict free clearance that considers aircradt performance
  • Interoperability by sharing the same trajectory view between air and all ground actors;
  • Predictability by improved trajectory accuracy and sharing information updates throughout the flight;
  • Flexibility by matching the trajectory with the Airspace User needs;
  • Flight efficiency: flight is managed closer to its optimal profile;