In the worldwide search for a more sustainable aviation, long haul flights are lacking for solutions. All the sustainable propulsion technologies which are being explored and developed nowadays are mainly applicable to short range flights. Long haul flights over the European airspace, for example leaving from Europe towards middle-east countries, are an example of traffic flows for which we need to find new solutions to take a step forward in the sustainability challenge. ​

Migratory birds such as geese often fly in formation to save energy by taking advantage of the changed airflow in each bird's wake. Like a bird, a moving airplane leaves a wake of disturbed air, creating an updraft that allows a following aircraft to cut down on engine thrust, fuel use and emissions. The project will seek to introduce this notion of wake energy retrieval (WER) into air traffic operations over continental Europe.