GEESE and ATM: Wake Energy Retrieval collaboration achieves new milestones

Last year Airbus, in partnership with airlines and Air Navigation Service Providers (ANSPs), successfully completed a new phase of trials for the SESAR Joint Undertaking (JU) GEESE project.

GEESE stands for "Gain Environmental Efficiency by Saving Energy" and was launched in 2023. Co-funded by the European Union (EU), it aims to map out how to enable and scale Wake Energy Retrieval (WER) operations across Europe.

How does Wake Energy Retrieval save fuel?

The “WER” technique sees a pair of airliners flying in formation, allowing the trailing aircraft to benefit from the uplift generated by the preceding aircraft’s vortices, reducing the thrust required from its engines. Once operational, wake energy retrieval has the potential to make fuel savings of up to 5% on long-haul flights. GEESE, which is part of the EU’s SESAR initiative, aims to map out how to enable and scale WER operations across Europe. WER was explored by Airbus, as part of its fello’fly concept and later adopted by Europe’s SESAR. Both “fello’fly” and “GEESE” are a ‘nod’ to the ability of migrating geese to efficiently fly in formation.

SESAR JU GEESE project flight trial results

The GEESE trials were led by Airbus, who partnered with airlines Air France, Delta Airlines, French bee, and Virgin Atlantic – using their A350 aircraft. Operations partners included AirNav Ireland, DSNA, EUROCONTROL, and NATS. Between September and October 2025, the team achieved eight pairings (out of 11 attempted) over the North Atlantic to test the process for how these flights should interact within the ATM ecosystem on their way to the meeting point, before starting the paired flight. Pairs were mixed and the airlines worked with each other to determine the best options based on their schedules. Notably, while the A350 was the aircraft used in the trials, any aircraft capable of long haul flights could have been used.

Overall, the partners successfully co-validated the operational process needed to guide two independent commercial flights to meet at a precise time and place, while maintaining full vertical separation and complying with air traffic regulations. While the actual wake energy retrieval flights have not yet been tested with airlines [i.e. given their mandatory vertical separation], the successful rendezvous pairing process is a crucial first step towards that goal.

Authored on

Mon, 02/16/2026 - 15:58

SESAR JU GEESE project team

From left to right: Laura Montironi: System Multi-Programme Project and ATM Engineer and GEESE Project Coordinator; Heidi Démoulins: Flight Test Operation Engineer; Imad Lebbos: Pairing Assistance Tool Function Owner.

From left to right: Laura Montironi: System Multi-Programme Project and ATM Engineer and GEESE Project Coordinator; Heidi Démoulins: Flight Operations Engineer; Imad Lebbos: Pairing Assistance Tool Function Owner.

Of the trials conducted, 75% successfully reached the rendezvous position at the designated time. The trials also confirmed that the PAT could bring two aircraft departing from different locations and at different times to a single geographic point, thereby simulating a rendezvous pairing. Notably, had these six flights included their respective cruise phases (i.e. using WER), then the total potential fuel saving would have been 12 tonnes (an average of two tonnes per flight, or roughly the amount needed for a flight from Toulouse to Madrid).

Pairing the aircraft: Four key steps

The trials validated a rigorous four-step process, designed to have the least impact on the ATM ecosystem:

• Digital coordination: The Airbus Pairing Assistance Tool (PAT) calculates new flight paths and meeting instructions in real-time. For the trials, in order to ensure all airlines were prepared for the trial flight, we needed to pre-plan the pairings in advance based on the airline scheduling. (Once WER would be put in real operations, pairings would also be identified after take-off - i.e. ‘opportunistic’ pairing.)
• Operational/feasibility assessment: Airline dispatchers in the OCC, pilots, and Air Traffic Control (ATC) review the new routes to ensure they are operationally viable. This is when the official GO/NO-GO is generated and the new flight paths are shared with the pilots in the form of a secondary flight plan with GPS coordinates of the rendezvous point.
• The adjustment: The ‘follower’ aircraft alters the route to join the other by activating the secondary flight plan in the Flight Management System (FMS). In the cockpit, this is managed automatically by the FMS’ “Required Time of Arrival” function. The latter adapts speed and direction to arrive at the rendezvous at the exact time required.
• The handshake: In the future, when the aircraft arrive at the rendezvous point, they will engage the WER functions required to facilitate the reduction of fuel consumption.

Authored on

Mon, 02/16/2026 - 16:02

Aircraft pairing visualisation with Airbus tool

The PAT mentioned above, is a centralized tool developed by Airbus, to which airlines, OCC and ATC actors have access to via an interface whose prototype for the trials was developed together with EUROCONTROL. Moreover, since it sits within Airbus, no physical changes to the aircraft were needed for these trials – as they can use existing onboard technology such as the standard Flight Management System (FMS) and autopilot. Therefore the challenge was to organise the mission pairings on ground (using the PAT) and put in place the right procedures and flight plan provision for the pilots to execute.

What’s the next phase of the project? – “GEESE 2”...

Going forward, the success and momentum of the trials described above have unlocked the next phase of the EU’s GEESE initiative, “GEESE 2”, with two main objectives: Firstly, to continue working on the integration of the WER concept into the ATM ecosystem, as well as widening the feasibility demonstration to new airlines, new airspaces and new traffic flows. Secondly, to mature the definition of flight crew procedures supporting WER operations. Throughout GEESE 2 the aircraft separation will remain the same as for GEESE.

Furthermore, the PAT would be further tested within the ATM ecosystem to ensure that when WER is certified for use, that it is already familiar to the people required to implement and activate the steps necessary.

Importantly, GEESE 2 will continue to gather and involve the many partners already in GEESE: Airbus, NATS, DSNA, EUROCONTROL, AirNav Ireland, INDRA, Air France, Virgin Atlantic, Delta Air Lines, French Bee, UAB, CIRA, plus some new participants, including NavCanada, Lufthansa, SWISS, and Thales.

Authored on

Tue, 02/17/2026 - 09:26

SESAR JU GEESE project flight trial

In the meantime Airbus’ fello'fly project is working to mature the aircraft technology necessary to ensure the pair flight phase will be possible in a smooth and safe way. To this end, Airbus pilots and engineers will perform later this year some test flights to test an industrial solution that is compatible with equipment onboard its customers' aircraft in order to confirm its feasibility. Airbus will also take the opportunity to harvest more data about vortex aerodynamics, as well as flying closer formations with its own flight test aircraft.

Authored on

Thu, 02/12/2026 - 13:59

Visual element

Wed, 12/10/2025 - 14:59

sesar joint undertaking