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This proposed plasma jet technology could someday change space travel

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Jul 7, 2020, 5:12 PM EDT

Will traditional fossil-fuel-based jet engines someday go the way of the dinosaur? If award-winning Chinese scientist Jau Tang has his way it will come to pass sometime in the very near future by using the carbon-neutral propulsion techniques of air plasma induced by microwave ionization.

Tang, an acclaimed inventor and Wuhan University professor, and his Institute of Technological Sciences colleagues Dan Ye and Jun Li might be on the verge of revolutionizing jet and rocket engines, if his latest brainstorm can be scaled up and produced with equal results outside a laboratory environment.

The essential idea is that his prototype device turns electricity directly into thrust, with no fossil fuel usage required. How is this sorcery accomplished? The process utilizes microwaves to energize compressed air into a plasma state and directing it outward as an expelled propellant similar to a jet engine. Sound like classic sci-fi? Somewhat.

Credit: Jau Tang and Jun Li/Wuhan University

“Essentially, the goal of this technology is to try and use electricity and air to replace gasoline,” Tang told Futurism. “Global warming is a major threat to human civilization. Fossil fuel-free technology using microwave air plasma could be a solution. I think the jet engine is more efficient than the electric motor, you can drive a car at much faster speeds. That’s what I have in mind: to combine the plasma jet engine with a turbine to drive a car.”

This revolutionary device is comprised of a microwave power supply, an air compressor, a compressed microwave waveguide, and a flame ignitor. Their findings were recently published in the online scientific journal AIP Advances.

Tang's ambitious belief is that his plasma jet technology could be harnessed to propel drones and within a decade be employed in powering automobiles, projectile weapons, speedboats, commercial and military aircraft, and even an ultra-modern kitchen stove that utilizes a microwave air plasma torch.

But before we junk all our current methods of heating and propulsion, the logistics and applications of this miraculous plasma jet are a long way from serious deployment. Plasma thrusters are not exactly new, and there have been numerous failed attempts to bring them to more widespread use, such as NASA's plasma thruster satellites used back in 2006.

The space agency's Dawn probe in 2017 used xenon plasma, which can't compensate for the friction in Earth’s atmosphere, and are not powerful enough to work in air transportation. As a solution, Tang's plasma jet thruster generates the high-temperature, high-pressure plasma needed using injected air and electricity. However, some sort of propellant would obviously be required in the vacuum of outer space.

Credit: Getty Images

The issues here lie not within the viability of a working prototype, but with the actual parameters and obstacles behind constructing a working air propulsion vehicle or aircraft around it. Ideas that generate success in a controlled lab setting often can't be replicated in the real world.

“The steps toward realization of a full plasma jet engine would cost lots of money, time and energy,” Tang added. “Such investment is beyond our present resources. Such tasks should be taken by aerospace industries or governmental agencies.”

One of the greatest hurdles for Tang's jet engine is that his team's prototype currently provides a mere 10 newtons of thrusts, which is the equivalent of an average-sized Estes hobby rocket. For this machine to lift an entire airplane, its output would have to be boosted exponentially. For example, the current Air Force One 747-200B jet's four engines deliver nearly 240,000 newtons of thrust, making the amount of electricity generating batteries to produce this type of power using Tang's novel approach impossible with today's technology.

"That’s a common mindset for scientists," Christopher Combs, aerodynamics researcher at the University of Texas at San Antonio, noted to Futurism. “That’s what us academics do, we figure out the physics and say, ‘Well I don’t want to make a product.' It’s kind of a common refrain to see people in academia who have had something that gets a lot of attention.

"You’re talking about scaling something by five orders of magnitude — more than 100,000 times! Which almost never works linearly. Lots of engineering happens in the middle. Does this thing just become a flying Tesla battery?” Combs said. “With the weight of these batteries, you don’t have room for anything else.”

Credit: Getty Images

Until battery technology improves in the upcoming decades, Tang's jet might not make it off the ground, but it could be suitable for smaller aircraft and limited-use aerospace launch vehicles. His team's research is still in the early stages of development, and there are many promising components to his plasma jet creation that may come to fruition as more obstacles are cleared.

“I’m rooting for this, and I’d love to see it pan out,” Combs added. “But the scientist in me has some questions and some concerns.”