Airspace management relies on modern systems on the ground and in the cockpit, yet neither currently connect with each other. In an age where data sharing is routine, two SESAR modernisation projects, ADSCENSIO and 4DSkyways, have developed ways to downlink flight information from the cockpit to air traffic control, and uplink data from the ground to the aircraft to fly more efficiently. Automatic dependent surveillance – Contract (ADS-C) enables aircraft to automatically log on and transfer accurate trajectory information from the flight management system to the ground. This extended projected profile (EPP) gives the controller a better understanding of where conflicts may arise and, along with ground-based conflict resolution algorithms, enables the controller to upload optimised flight profiles in the trajectory clearance. SESAR’s 4DSkyways industrial developed solution within the framework of trajectory-based operations (TBO) improves conflict detection and resolution, and enables controllers to handle increasingly complex traffic. It also enhances safety by automatically checking routes, saves time spent on the voice frequency, and reduces errors.
“We want to push the envelope during the flight execution phase,” says 4DSkyways Project Manager, Peter Alty, EUROCONTROL. “Network performance is key, and more accurate, timely, trajectory information can support innovative use cases such as tactical resolution advisories and descent when ready.” During one of the project’s validation exercise in Geneva, aircraft equipped with ADS-C technology successfully downlinked intent flight management system information, and controllers uplinked controller pilot datalink communications (CPDLC) messages compliant with ATN-B2 standards. Transmissions included complex clearances including latitudinal and longitudinal coordinates to facilitate optimum trajectories. “TBO is about sharing the common plan for a flight among all the stakeholders to improve capacity and performance.” In a first implementation, Maastricht area control centre began exchanging ADS-C EPP messages in May 2022 and Airbus reports more than 100 equipped aircraft in operational service. “As more aircraft equip with ATN-B2, the more benefits we can deliver,” adds Alty.
SESAR is developing technical and operational solutions to meet the Common Project #1 requirement for European air navigation service providers (ANSPs) to exchange trajectory data with flights in Europe from 2027. The ADSCENSIO very large-scale demonstration evaluated real-life flights in several operational scenarios, looking in particular at four functions. In the case of “facilitating optimised descent”, trajectory information downlinked from the aircraft at top of descent enables the controller to provide speed modifications to improve fuel consumption, explains Project Manager, Didier Velay, DSNA. “Another example is consistency management, where ADS-C data can be used to verify estimated time of arrival at specific waypoints.” Consistency checks ensure the synchronisation of the air and ground trajectories. The project also addressed complimentary connectivity using SATCOM and VDL data link with the aim of minimising frequency congestion, and tested automatic downlink tracks without crew login.
“Results so far are extremely positive says Didier Velay: “We validated a prototype ADS-C common service and delivered a document for standardisation that sets the solution on the way to industrialisation. We have built a library of data from 5,000 live operational flights and controller feedback is extremely positive about what can be done with more accurate trajectory data.”
More about 4DSkyways
https://www.sesarju.eu/news/4dskyways-convincing-stakeholders-invest-trajectory-management
More about ADSCENSIO
SESAR 2020 ADSCENSIO and 4DSkyways joint dissemination event:
