Engineers at the Massachusetts Institute of Technology (MIT) have created an aircraft that doesn’t get its thrust from propellers and turbines, but ionic wind — a silent flow of ions that generates the thrust required to keep the plane airborne. The plane is not dependent on fossil fuels and doesn’t have any moving parts.
“This is the first-ever sustained flight of a plane with no moving parts in the propulsion system,” says Steven Barrett, associate professor of aeronautics and astronautics at MIT. “This has potentially opened new and unexplored possibilities for aircraft which are quieter, mechanically simpler, and don’t produce combustion emissions.”
It is expected that the silent technology will be used to run drones, which are easily recognizable by their tell-tale hum today. Barrett also expects that when combined with more conventional combustion systems, the technology could be used to create more fuel-efficient hybrid passenger planes and other large aircraft.
Ionic wind is also known as aerodynamic thrust. It was first recognized in the 1920s and in simple terms, is a wind or thrust that is produced when a current is passed through a thin and thick electrode. For years, it was more or less a hobbyist project. Projects utilizing ionic wind were usually desktop decorations tethered to large voltage supplies that hovered briefly in the air. This begun to change when Barrett began research on a possible propulsion system that had no moving parts nine years ago.
The MIT team’s final design bears resemblance to a lightweight glider. It weighs about five pounds and has a 5-meter wingspan. It comes with a collection of thin wires, which act as positively charged electrodes. A network of thicker wires run alongside the backend of the wings, serving as negative electrodes. The fuselage carries a stack of lithium polymer batteries, which are designed to convert the output to a sufficiently high voltage to propel the plane.
The plane has flown multiple test-flights across the gymnasium in MIT’s duPont Athletic Center. It was found that the plane could sustain flight easily over a distance of 60 meters.
Barrett’s team continues to work to improve their design, with a focus on producing more thrust using less voltage.
“It took a long time to get here,” Barrett says. “Going from the basic principle to something that actually flies was a long journey of characterizing the physics, then coming up with the design and making it work. Now the possibilities for this kind of propulsion system are viable.”