When spaceship tech makes its way to terrestrial flight.
If Steven Barrett (Associate professor of aeronautics and astronautics, MIT) and his team of engineers have their way, we may soon have airplanes that fly without propellers or turbines, but rather a flow of ions, similar to the TIE Fighters from Star Wars.
As proof of concept, Barrett’s team have created a lightweight glider that weighs about five pounds and has a five-meter wingspan with a stack of lithium-polymer batteries that supply 40,000 volts of electricity to positively charge wires under each wing. Once energized, the wires strip away negatively charged electrons from the surrounding air molecules, leaving behind ionized air molecules which are attracted to the negatively charged electrodes at the back of the plane.
This movement of air molecules leads to collisions of ions that create a thrust, propelling the airplane forward. Apply enough voltage, and you’ll get enough thrust for sustained flight. In their experiments, the team has successfully flown their model plane 60 meters via ionic thrust alone, proving the promise of the concept.
An ion-driven plane would be silent and invisible in infrared while being relatively eﬃcient. Best of all, there would be none of the carbon emissions from today’s vehicles as there is no combustion reaction involved. The lack of moving parts on the plane also means that overall maintenance costs should be much lower than conventional planes.
However, because ionic wind propulsion requires a large amount of space between electrodes, lifting an aircraft and its power supply would require a very large air gap. This means the electrodynamic thrusters would probably encompass the entire vehicle, and that the vehicles would need a large power source to run it all. A combination of highly eﬃcient fuel cells and solar panels perhaps?
Think of ion-drive as a propulsion system and you start to see the vast potential in the technology beyond flight. If we could apply this to motor vehicles for example, we’d probably drastically cut down on the amount of carbon emissions from transportation, while getting one step closer to personal flying vehicles.
ION THRUSTERS IN SPACE
While Ion propulsion is only being experimented for use in Earth atmosphere, the technology is not within the realm of science fiction. The first spacecraft to test the use of ion thrusters in space was the SERT-1, launched by NASA back in 1964. Today, ion thrusters are the primary forms of propulsion for deep space craft such as satellites and probes. In 2017, NASA’s latest X3 Ion thruster, developed in collaboration with the University of Michigan, broke records for maximum power output, thrust and operating current. NASA claims that the technology is on track to ferry people to Mars within the next 20 years.
PICTURES CHRISTINE Y. HE, MIT ELECTRIC AIRCRAFT INITIATIVE, 123RF