Could ‘flying piano’ help transform air cargo?

American start-up Aerolane is looking for the secret of aerial surfing.

Geese already know how to do it. When you see them flying in a V-shaped formation, they surf the air currents created by the members of the formation in front of and around them.

At an airport in Texas, Todd Graetz hopes to use the concept to disrupt the air cargo market.

Aerolane mimics the tricks used by migrating birds, using modified aircraft towed into the air by another aircraft.

Smoke coming from the lead aircraft allowed cameras installed in the towed aircraft to pick up eddies in the air, which the glider can use to stay aloft.

Their latest test aircraft is known as the “flying piano” due to its poor gliding characteristics.

Its two engines idle for electrical power while it glides along with the propellers spinning for purely aerodynamic purposes.

Other tests measured tension in the pull cable.

They noticed that the line had loosened, indicating that the glider was surfing along the currents generated by the aircraft ahead.

Aerolane’s plan is to feed all that data into a program that will guide the unmanned cargo plane through wakes and turbulence to take advantage of long-distance gliding capabilities without burning fuel.

One or more such cargo planes could be towed by a jet that was also carrying cargo to a destination where it would land autonomously.

The only fuel cost would come from the supply of the towing aircraft engines.

In theory, it should work like a truck pulling a trailer, with heavy loads making air currents. Mr. Graetz calls it “a combination of sailing and surfing.”

The same idea occurred to Airbus, which tested the technique in 2021 with two A350 airliners flying 3 km (1.9 mi) apart across the Atlantic.

Although the planes were not connected by a tow cable, the experiment saw one plane win a lift from the wake of the leading A350 to reduce CO2 emissions and fuel burn.

Mr Graetz, a pilot with 12 years’ experience, founded Aerolane with Gur Kimchi, a veteran of Amazon’s drone delivery project, on the basis that “there has to be a better way to get more out of existing aircraft”.

The project raised eyebrows among experienced pilots. Flying large gliders in commercial airspace means meeting strict flight safety regulations.

For example, the tow plane must be confident that it can release the tow rope at any point in flight, knowing that the autopiloted glider can reach the runway without falling on the local population.

Aerolane says the small electric motor driving the propeller will act as a safety net on their cargo gliders, giving them enough juice to go around again if the landing doesn’t look bad, or divert to another location nearby.

Mr. Graetz counters that Aerolane employs active commercial pilots who are stubborn about the practical aspects of the project.

“We brought in outside counsel to be devil’s advocates,” he adds.

He says the big freight companies are interested in anything that allows them to reduce the cost of delivery.

In addition to fuel costs, airlines also have to think about emissions from jet engines and pilot shortages.

James Earl, a former RAF helicopter pilot and aviation consultant, thinks Mr Graetz may be on to something.

“It stands to reason that gains can be made with AC and a combination of efforts in the sky. And any innovation in cargo space is good.”

But he cautions that public acceptance of non-powered cargo flights over built-up areas is another matter entirely.

“It should have good gliding range to get to the landing site in the event of a major failure of the towing aircraft. Whether that can be effectively communicated to the public is another matter.’

Mr. Graetz responds that his team has complied with every FAA request so far. “The FAA has always been very risk averse. That’s their business!”

Fred Lopez spent 36 years in air traffic at the cargo giant UPS. As he says, he has invested “my whole grown-up life” into developing the most cost-effective way to operate air cargo.

Mr. Lopez admits he was deeply skeptical about cargo gliders when Aerolane first approached him. But the prospect of significant fuel savings won him over, and he now sits on their advisory board.

Reducing fuel costs is an obsession in civil aviation. When the upright wingtips seen from the cabin window became a standard design feature, airlines reduced fuel costs by approximately 5%.

But gliders only consume the fuel required by their towing aircraft. If this is also a cargo plane, a couple of gliders towed by a single jet represents a significant reduction in fuel consumption for a large shipment.

Aerolane’s initial design uses their autopilot plus what Mr. Lopez calls a human “safety pilot.” This should facilitate certification from the FAA.

“Aerolane is not trying to change everything at once,” he says.

Their ultimate goal is autonomous operation using artificial intelligence, or as Mr. Lopez puts it, “taking the pilot out of the seat.”

And if a flying piano can surf, who knows what’s possible?