What would engineers need to do to get airliners to save anywhere between five and ten percent in fuel? Well, make them fly in formation like a herd of migrating geese, it turns out.
Aerospace corporation Airbus is examining a new way for passenger jets to save fuel and cut emissions, and this concept, which the firm has dubbed fello'fly, will see planes fly closely behind one another.
When scientists and engineers are in doubt, they look at nature. This project was no different since birds are the masters of aerodynamics.
Airbus's research incubator Airbus UpNext studied the aerodynamic efficiencies flying in formation provides to the geese and decided to test the idea with two passenger jets, CNN reports. Back in March 2020, an early test involving two Airbus A350 aircraft was conducted. The investigation will be expanded in 2021 with the involvement of Frenchbee and SAS airlines.
Bringing airliners safely together
When airliners fly nearby each other, the trailing aircraft will be able to take advantage of the vortices of rotating behind by the leading plane's wing tips. This "vortex surfing" technique is taken from geese.
Bour Schaeffer, an experienced flight-test engineer, told CNN, "[The pilots] will be 1 1/2 to 2 nautical miles away from the leading aircraft, and slightly offset, which means they are on the side of the vortex. It’s no longer the vortex, it’s the smooth current of rotating air which is next to the vortex, and we use the updraft of this air.”
This technique can save A350s anywhere between 5 and 10 percent in fuel, which is an "enormous number" according to Schaeffer. Moreover, this could potentially cut CO2 emissions by 3–4 million tons per year.
The tests of two Airbus's 350 aircraft will begin this year. According to test results, 2021 could see trial runs in oceanic airspace.
However, it should be noted that making airliners fly in such formation could come with risks. If or when Airbus wants to make this technique mainstream, it will need to convince government aviation agencies and service providers first.
You can watch and learn how a fello'fly flight works here: