DIY Network

New Advances in RC Electric Airplane Motors "Going brushless" with new and super-efficient motors From "Radio Control Hobbies" episode RCH-408

	Media Watch a video showing the electric RC planes in action.

Chris Chianelli, host of DIY's Radio Control Hobbies visits a flying field just outside Chattanooga, Tennessee for a look at the latest technology in electrically powered flight in the form of brushless out-runner airplane motors. These advanced electric motors offer several advantages over glow-fuel and gas-powered models. They are reliable, efficient, quiet and as powerful as their nitro or gas powered counterparts. (In some cases, even more powerful.)

Along with the advanced electric motors, Chris checks out the newest lithium batteries available. The combination of brushless motors and new advances in battery technology has changed the face of electrically powered flight. For example, just a few years ago, a simple, electric park flyer could only fly for only about 3 minutes. The new technology allows some aircraft to attain flight durations exceeding 20 minutes.

advertisement

The Basics of Brushless

In the estimation of some of hobbyists, electric-powered flight is quickly becoming the future for RC aircraft. Included in the models powered by this new technology are RC planes with wingspans up to 90 inches and aerobatic models capable of straight-up vertical flight maneuvers.

Jim T. Graham, electric-motor specialist with Hobby Lobby.

Conventional motors utilize internal brushes that push against the spinning commutator. This results in mechanical drag and heat build-up. By contrast, the new brushless motors don't suffer from those mechanical burdens. "Brushless" essentially means that none of the internal moving parts are in contact with each other. In that way, all of the power coming from the battery is directly channeled toward simply spinning the prop. The result is in an extremely efficient operation.

Jim T. Graham of Hobby Lobby©, one of the industry's leaders in electric-power motors, is a big believer in the technology. According to Jim, not only are there new electrically powered models on the market, but there are also options for hobbyists to convert their gas-powered planes to electric.

Electric motors are available in a wide range of sizes. The half-dollar-sized AXi 2204® (figure A) is used in 3D flyers that may weigh a total of less than six ounces. At the other end of the spectrum is the AXi 5330® (figure B) that can power a 22-pound plane, spinning a 20-inch propeller at 9000 rpm.

Figure A

Figure B

One of the most impressive of Jim T's planes is the Condor P-38®, a war-bird replica with an 88" wingspan that's powered by a 60-size out-runner brushless motor (figure C). The motor utilizes a radial mount, so that it can be mounted directly to the firewall (figure D). The lithium-polymer battery is mounted directly below the engine so that it can be air-cooled while the plane is in flight.

Figure C

Figure D

Another model that highlights the enhanced performance powered by these engines is the Alpha MIG®, a ducted-fan model specifically designed for electric power (figure E). It's powered by a brushless motor with lithium-polymer battery and is capable taking off directly from a grass surface (figure F). The MIG is a highly stable flyer and has a top flight speed is about 50 mph.

Figure E

Figure F

Page  1 | 2 | 3