MIT scientists have built and flown the first-ever Star Trek-inspired plane with no moving parts, paving the way for quieter, simpler aircraft with no combustion emissions.
Instead of propellers, the light aircraft is powered by an "ionic wind"—a silent but mighty flow of ions, which generates enough thrust to propel the plane over a sustained, steady flight.
Unlike turbine-powered planes, the aircraft does not depend on fossil fuels to fly, according to the study published in the journal Nature.
The new design is completely silent unlike propeller-driven drones.
"This is the first-ever sustained flight of a plane with no moving parts in the propulsion system," said Steven Barrett, associate professor at Massachusetts Institute of Technology (MIT) in the US.
"This has potentially opened new and unexplored possibilities for aircraft which are quieter, mechanically simpler, and do not emit combustion emissions," Barrett said.
Such ion wind propulsion systems could be used to fly less noisy drones in the near future, researchers said.
Barrett said the inspiration for the team's ion plane comes partly from the movie and television series, "Star Trek." He was particularly drawn to the futuristic shuttle-crafts that effortlessly skimmed through the air, with seemingly no moving parts and hardly any noise or exhaust.
"This made me think, in the long-term future, planes shouldn't have propellers and turbines," Barrett said.
"They should be more like the shuttles in 'Star Trek,' that have just a blue glow and silently glide," he said.
It was largely assumed that it would be impossible to produce enough ionic wind to propel a larger aircraft over a sustained flight.
The team's final design resembles a large, lightweight glider.
The aircraft, which weighs over two kilogrammes and has a five-metre wingspan, carries an array of thin wires, which are strung like horizontal fencing along and beneath the front end of the plane's wing.
The wires act as positively charged electrodes, while similarly arranged thicker wires, running along the back end of the plane's wing, serve as negative electrodes. The fuselage of the plane holds a stack of lithium-polymer batteries.
Barrett's team designed a power supply that would convert the batteries' output to a sufficiently high voltage to propel the plane.
In this way, the batteries supply electricity at 40,000 volts to positively charge the wires via a lightweight power converter.
Once the wires are energised, they act to attract and strip away negatively charged electrons from the surrounding air molecules, like a giant magnet attracting iron filings.
The air molecules that are left behind are newly ionised, and are in turn attracted to the negatively charged electrodes at the back of the plane.
As the newly formed cloud of ions flows towards the negatively charged wires, each ion collides millions of times with other air molecules, creating a thrust that propels the aircraft forward.
