SCIENCE

Back to the Future With Aluminium Wings

NASA and MIT scientists think they have found a solution to improve aircraft wing performance.
17 March, 2017
Today's complicated aircraft wings, with their flaps and ailerons, could soon be flying back to the future.
Together, NASA and engineers at the Massachusetts Institute of Technology (MIT) are reinventing wings in much the same way the pioneering Wright brother inventors first created their own.

The mechanism on those first flying machines used wires and pulleys to bend and twist wings made of canvas and wood. Today, using 21st century materials mounted on an aluminium frame, the new inventors are testing agile, bending wings that are covered in small overlapping pieces akin to feathers or scales.
The new wing architecture relies on just eight materials, including carbon fiber and tiny, lightweight strips of Kapton foil, which is already used in the space program. For example, the James Webb Space Telescope will rely on the Kapton polyimide film to protect the sunshield, and it can be used in additive manufacturing (3D printing) processes. With the five-foot long prototype wings, these high-tech pieces can move across each other as the wing flexes while remaining smooth on the outer surface of its skin.

Each wingtip is twisted by a small motor while in flight, which allows the wing to change shape and reduce drag, increase the angle to change lift, and reduce vibration, all without conventional tools.
Image: Techolic; Kenneth Cheung/NASA
But does it work? When the wing was tested in a wind tunnel, the scientists discovered that it at least meets the same aerodynamic properties of a conventional wing, but at about one-tenth of the weight.

"I think we can say it is a philosophical revolution, opening the gate to disruptive innovation," said Vincent Loubiere of Airbus, a lead technologist for emerging technologies and concepts. "The perspectives and fields this approach opens are thrilling."
The flight itself isn't the only thing that's exciting, because the newly invented wing is expected to dramatically reduce fuel consumption for an aviation industry that is constantly investing in new ways to achieve the cost savings and reduce environmental impact through lighter weights – and has long relied on aluminium components to do so.
The Wright Flyer inspired the look of this morphing airplane wing. Image: Boredlion.
Neil Gershenfeld, the director of MIT's Center for Bits and Atoms, says that researchers have been working on this problem for years to no avail. Most efforts relied on deforming the wing by using mechanical controls placed within it, but they were always so heavy that they canceled out efficiency advantages while adding complexity and reliability issues at the same time.

The new wing avoids those problems, but also requires a simple and completely different approach to manufacturing. The MIT and NASA team envision building the wings in much the way that small Lego pieces are assembled into the whole. The light composite aircraft wings currently in use rely on bulky large, specialized equipment for layering and hardening the material, but the new modular structures could be rapidly manufactured in mass quantities and then assembled in place.
Image: Pexels
While the prototype was built by hand, the scientists think that miniature robots can do that job – and they've already developed a prototype for the robots too. They also think that safety inspection robots could find and replace broken parts with ease, keeping the new wings in optimal shape at all times.

The next tests for the new wing will be in unmanned drones, but the technology is already being eyed for wider application in windmill turbines, skyscrapers and other construction challenges.
Banner image: Inverse; Kenneth Cheung/NASA