Si­lent air­craft may lead to quiet drones

Star-Telegram (Sunday) - - Local & Texas - BY MAL­COLM RITTER

A nearly si­lent, drone­sized air­craft has shown it can fly, thanks to a sci­en­tist who was in­spired by watch­ing “Star Trek” as a child.

With nei­ther propellers nor jets, the airplane gets its thrust by ap­ply­ing a strong elec­tric field to the air. That gen­eral idea has been demon­strated at sci­ence fairs, but the new work shows it can power a free-fly­ing airplane.

So can peo­ple look for­ward to trav­el­ing in planes that are al­most si­lent and emit no air pol­lu­tion?

“Not any­time soon,” says Steven Bar­rett of the Mas­sachusetts In­sti­tute of Tech­nol­ogy, who re­ported the re­sults in a study re­leased Wed­nes­day by the jour­nal Na­ture.

It’s not clear whether the tech­nol­ogy could work at such a large scale, he said in a tele­phone in­ter­view. And even if it can, it would take a few decades to de­velop such planes, he said.

Be­fore that, the ap­proach might be used in airplane-like drones that per­form tasks like en­vi­ron­men­tal mon­i­tor­ing and surveil­lance, he said. As drones be­come more com­mon in ur­ban skies, the lack of noise would be an ad­van­tage in mak­ing them less both­er­some to peo­ple on the ground, he said.

The Na­ture paper re­ports the re­sults of 10 test flights inside an MIT ath­letic build­ing. With a wing­span of about 16 feet, the five-pound plane sailed along at about 11 mph. Each flight cov­ered about 60 yards.

Bar­rett, 35, said he was in­spired as a child by watch­ing “Star Trek” tele­vi­sion episodes and movies, where he was struck by the shut­tles that flew with no mov­ing parts in their propul­sion sys­tems.

He re­called think­ing, “There should be a way things should fly without hav­ing propellers and (jet) tur­bines.”

As an adult, he fo­cused on that and came across a con­cept called “ionic wind.”

For the MIT airplane, that in­volves a se­ries of thin wires at the front of the plane that gen­er­ate a pow­er­ful elec­tric field. The field strips elec­trons from air mol­e­cules, turn­ing the mol­e­cules into pos­i­tively charged par­ti­cles called ions. Those ions flow to­ward neg­a­tively charged parts of the plane, col­lid­ing with or­di­nary air mol­e­cules and trans­fer­ring en­ergy to them. That pro­duces a wind that pro­vides thrust for the plane, Bar­rett ex­plained.

A sim­i­lar process has long been used in outer space to pro­pel some space­craft, he said.

Bar­rett said he hopes to find a way to elim­i­nate the “very slight buzz” one can hear.

“I think they’re onto some­thing here,” said Pat An­der­son, a pro­fes­sor of aero­space en­gi­neer­ing at the Day­tona Beach, Florida, cam­pus of Em­bryRid­dle Aero­nau­ti­cal Uni-

WITH NEI­THER PROPELLERS NOR JETS, THE AIRPLANE GETS ITS THRUST BY AP­PLY­ING A STRONG ELEC­TRIC FIELD TO THE AIR.

ver­sity. He had no role in the re­search.

He called the re­sults im­pres­sive. But the ex­per­i­men­tal air­craft lacks the range and en­durance to serve as a use­ful drone, and it’s not clear whether the tech­nol­ogy could be scaled up to fix that or be­come use­ful for pro­pel­ling a pas­sen­ger plane, he said.

Newspapers in English

Newspapers from USA

© PressReader. All rights reserved.