Experimental plane flies almost silently

Concept could lead to quiet drones for surveillance, more

NEW YORK — A nearly silent, drone-sized aircraft has shown it can fly, thanks to a scientist 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.

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,” where he was struck by shuttles that flew with no moving parts in their propulsion systems. He recalled thinking, “There should be a way things should fly without … 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 them into positively charged particles called ions. Those ions flow toward negatively charged parts of 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.

“I think they’re onto something here,” said Pat Anderson, a professor of aerospace engineering at the Daytona Beach, Fla., campus of Embry-Riddle Aeronautical University. He had no role in the research.