Like Star Trek.
The Massachusetts Institute of Technology (MIT) scientists have developed a breakthrough drive for aircraft heavier than sound that does not need moving parts in the powerplant.
The drive provides an ionic wind that is produced on board the aircraft. It creates a sufficient move for its stable and quiet flight.
When tested, a small unmanned aircraft flew 60 meters on such an ion wind. Successful tests have shown that in the near future ion drive systems could be used to produce silent drones. They will also be able to combine with conventional combustion systems to make them more economical.
The study was published in the journal Nature.
For more than a century, machines heavier than air are flying overhead. With the exception of gliders, they move with moving parts such as propellers, turbine blades, or blowers. They are powered by fossil fuel combustion or battery power, producing constant noise.
The ion wind drive is quiet and does not need moving parts. It opens up new, so far unexplored development possibilities for mechanically much simpler aircraft that do not produce combustion emissions.
The research team leader, Steven Barret, reportedly drew inspiration from the Star Trek television series, where the shuttles glided smoothly without noise and seemingly without moving parts.
He used a well-known physical principle, an electro-aerodynamic thrust consisting of a strong ion flow, for almost a hundred years. This occurs when current flows through the air between the thinner and thicker electrodes, using a sufficiently strong voltage.
The calculations confirmed the feasibility
Various enthusiasts use this principle to create light-duty aircrafts flying above the table. However, these are connected by cables to large power supplies to produce a sufficiently strong ion current.
Given such constraints, it was more or less assumed that it was impossible to create an ionic wind on a stable drive of a larger aircraft.
But, based on the calculations, Barett found it possible, and the next nine years of development gave him the truth.
On the “wings” of the ions
He created a unique aircraft in the shape of a light glider with a wingspan of 5 meters. Its weight is less than two and a half kilograms. Under the front wing it has stretched rows of wires.
Initially, they are thinner, serving as positively charged electrodes, at the end thicker, negative electrodes. The fuselage of the aircraft is equipped with lithium-polymer batteries and a converter, allowing the supply of current at 40,000 volts.
The front electrodes attract negatively charged electrons from the surrounding air molecules, similar to the iron filings magnet. The remaining air molecules remain positively ionized and are attracted to the negatively charged back electrodes. These are colliding with other air molecules in their path, creating a thrust that drives the aircraft forward.
The tests of the aircraft took place in the gym, where the maximum possible runway was 60 meters. The aircraft produced a sufficient thrust for the continuous flight of the entire distance.
Like Star Trek
Ion propulsion aircraft represents a huge step forward, because so far no heavier equipment than several grams has been able to get into the air. Still, according to Barett, it is not an aircraft that might be useful. To do so, it must be more efficient and fly longer routes in open space.
Therefore, researchers are further working to increase the efficiency of the drive to create a stronger ion wind at less voltage. They also plan to increase thrust density, which would reduce electrodes.
They assume that they could tighten the technology so that the drive is not visible at all and the controls to change direction and height are separate. Then it will be more like a Star Trek flying machine.