Andrew Moore / The Bulletin

Airplanes powered by electric motors are in the early stages of development, but Bend entrepreneur Greg Cole is charging ahead with his own design.

Cole, who previously worked as the chief engineer of research and development at Lancair in Redmond and then left to form a company to build lightweight, carbon fiber sailplanes, has designed a two-seat, carbon fiber airplane that would run on a 40-horsepower electric engine powered by stacks of lithium ion batteries.

The plane wouldn’t be fast — its estimated cruise speed would be 130 mph — and wouldn’t have much range, probably between 100 and 150 miles, but it would cost a fraction to fly compared with its gas-guzzling cousins.

In its current design, Cole’s plane — the Goshawk — would be able to fly for one hour on a full battery charge, he said. Using an engine that consumes 15 kilowatts, and assuming electricity costs 9 cents per kilowatt-hour (the U.S. average, per the federal Energy Information Administration), Cole said the plane’s “fuel” costs for a one-hour flight would be roughly $1.35.

By comparison, piston-powered airplanes that burn traditional low-lead aviation gas — which was selling Thursday for $4.89 per gallon at Bend Municipal Airport — have substantially higher hourly fuel costs, starting at about six gallons per hour for entry-level trainers, Cole said. Jets burn even more.

“I can’t even go 100 miles on my bike for $1.35 because you’d spend way more than that on Snickers bars,” Cole said.

Aviation is a lifelong passion for Cole, and he is serious about the Goshawk.

People in the aviation world are paying attention.

In April, Cole was invited to the CAFE Foundation 2008 Electric Aircraft Symposium in San Francisco to share his design for the Goshawk.

The Santa Rosa, Calif.-based CAFE Foundation is a nonprofit that promotes aviation technology and development for small airplanes.

“It was received enthusiastically,” the foundation’s president, Brien Seeley, said of Cole’s presentation of the Goshawk. “He’s a very strong, reputable designer who’s created some singularly popular and exceptionally capable vehicles, and so when he speaks, people listen.”

To help him get his design off the ground, Cole has begun soliciting investors. With $400,000, he believes he could have a prototype flying within one to two years. In the meantime, Cole is funding the plane’s development himself.

Cole has already started work on the prototype of his electric plane in a cluttered hangar at the Bend airport that’s home to Windward Performance, which is Cole’s sailplane company. Windward Performance is the only sailplane manufacturer in North America, according to Cole.

He and some of his Windward crew have created the mold for one of the Goshawk’s wings. It will be shipped to Cole’s manufacturing facility in Eugene where the mold will be covered with plies of carbon fiber, impregnated with resin, rigged to a vacuum device to remove air pockets and then cured in an industrial oven.

The wing, of course, is just one of many elements that will eventually form the Goshawk, all of which will be shipped back to Bend for assembly at the Windward hangar.

“It’s a huge commitment, a huge amount of work, and very expensive,” Cole said.

The Goshawk’s wings will be long and thin, similar to the wings of his sailplane, the SparrowHawk. Longer wings create less drag, Cole said, and the Goshawk will have a wingspan of 51 feet. And, like the wings on the SparrowHawk, the Goshawk’s wings will be detachable, making the plane easier to store.

The plane’s empty weight is projected to be 700 pounds, which includes 240 pounds of batteries, and will be able to carry an additional 500 pounds of passengers and baggage. It’s estimated it will have a top speed of 160 mph and will be able to climb to significant altitude, although an exact ceiling has yet to be determined.

“The extremely advanced method of manufacture, the materials selection and the sophisticated aerodynamic design are the elements that enable an airframe achieving this level of efficiency to be conceived and realized,” said Jake Ruhl, an aeronautical engineer and Windward Performance employee who is assisting Cole.

The Goshawk is lightweight and because it doesn’t need gas, it’s extremely cost-efficient to operate, Cole said. It also would reduce noise pollution because an electric motor emits only a low hum.

But Cole said the big sticking point will be its range. At 100 to 150 miles, the range isn’t suitable for most business trips, he said.

Cole’s confident, however, that as battery technology improves, the Goshawk will be able to fly farther. He estimates — using past advances in battery technology that show a doubling in capacity every two years — that battery capacities will improve fivefold in the next 10 years. If that occurs, Cole’s electric airplane, using the same 15-kilowatt electric engine, would be able to stay aloft for 500 miles on one charge by 2018.

“People fly for different reasons, and this would be fun for recreation,” he said. “But with battery-technology improvements, it could be used for transportation and could be revolutionary.”

Sound like science fiction?

Last December, a French consortium flew a plane powered by lithium ion batteries. In April, Boeing successfully flew a plane powered by hydrogen fuel cells. And a Slovenian company, Pipistrel, is already selling a self-launching glider propelled by an electric motor.

NASA also has had success earlier this decade flying unmanned solar-powered aerial vehicles.

In fact, Seeley, the president of the CAFE Foundation, believes the future of aviation will hum to an electric motor.

“I think we are going to move away from combustible fuels,” he said. “Not immediately — it’s going to take a significant number of years — but ultimately I think the technology will enable it.”

Cole sees some science fiction in his efforts. Noting certain films that depict a future with skies buzzing with aerial traffic, Cole believes those films portend what’s to come, a world where aviation — powered by electric motors — is cheap and accessible to the masses.

The future surely can’t look like a typical day of freeway traffic in Los Angeles, he says.

“This isn’t a crazy dream; it’s achievable,” Cole said. “We’re right at the cusp.”