The Electric Airplane
Quiet, smooth, dependable—shouldn’t we be flying these by now?
- By Peter Garrison
- Air & Space magazine, August 2009
Sonex Aircraft, LLC
(Page 3 of 4)
The aviation he is talking about is recreational: “I’m not looking beyond two seats.” His airplane will cost $50 an hour to operate; $30 of that is a reserve for replacing the battery pack after 500 to 1,000 charging cycles. Because the airplane itself has very low drag and is highly efficient, the cost of the electric “fuel” is negligible. Cole’s ultimate vision of sustainability is right out of the Whole Earth Catalog: A couple of small wind-powered generators on the roof of a hangar would, with sufficient wind, provide power for one or two flights a week. In a pinch, he concedes, “You could always top off from [an electric socket in] the wall.”
Cole has made little effort to publicize his project; Monnett, on the other hand, announced his “E-Flight Initiative” in 2007 at the Experimental Aircraft Association’s annual Oshkosh fly-in and displayed a mockup of the new powerplant. But a 59-year-old retired jeweler and self-taught engineer from New Jersey, Randall Fishman, stole a march on both Monnett and Cole. In 2008 Fishman, whom his friends used to call Doctor Gizmo, flew his single-seat electric airplane in front of cheering crowds at Oshkosh. The airframe is a discontinued Moni motor glider (built from a kit designed, coincidentally, by John Monnett before he started Sonex), modified and refitted with an 18-hp electric motor. It can cruise at 70 mph, using just 6 hp to stay aloft. A 90-minute flight consumes 5.6 kilowatt-hours of electricity—about 70 cents’ worth, at present rates. It recharges from a wall outlet in six hours.
“I used to like to fly ultralights, but they were powered by Rotax snowmobile engines,” Fishman says. “They were so loud. And after you flew for a while and landed, your body would still be vibrating.” In his pursuit of quiet, vibration-free flight, Fishman has been honored by the EAA, which recognized his contribution to light aircraft design with the 2008 August Raspet Award. (John Monnett is a previous winner, as is Pete Buck, though not for their work in electric power.) And this year the Lindbergh Foundation awarded him a $10,580 grant.
Like the Wright brothers, Fishman started with a bicycle. He used to have to pedal uphill to get to his jewelry store, and he didn’t want to arrive sweaty. When he saw an ad for an electric bicycle motor, he thought: That would be nice. More than 20 years, hundreds of thousands of dollars, and several electric conveyances—a scooter, an ultralight Trike, and the
ElectraFlyer-C—later, Fishman is working on a two-place electric airplane he says will be ready to fly this fall. With motor experts, he has developed an electric propulsion kit including 100-hp motor, battery pack and battery management system, and throttle to control the speed at which the batteries discharge.
“We’re using a lot of very inefficient, crappy technologies to waste the gas that we can get so cheap,” says Fishman. “Six-thousand-pound cars to move around people who weigh about 80 pounds. It seems normal to us. This is not the way we should be doing things.”
The irony of electric airplanes is that their economies are tiny. Since electric powerplants are confined, at least for the foreseeable future, to small, light, and slow airplanes that don’t require a lot of energy in the first place, the savings to be realized from using electricity—which is roughly equivalent to $1.50-a-gallon gasoline—is rather small (see “Miles per Kilowatt,” below) . Conventionally powered airplanes with the performance of electric ones use only one or two gallons of fuel an hour, so the difference in direct operating cost is negligible in comparison to the difference in initial outlay: for an airworthy gasoline engine, $100 per horsepower; for an electric powerplant, $400 or more per kilowatt. Greg Cole points out that in 10 years the price of gasoline will probably be “somewhere between bad and horrible.” Besides, the price of fuel isn’t everything; smoothness, quiet, reliability, and freedom from maintenance have value, as would the environmental benevolence of an airplane fueled entirely by locally harvested sunlight or wind.
Outside his hangar, Pete Buck and I survey the rows of tied-down airplanes, sailplanes, and sailplane trailers. Nobody is flying today, because there’s not enough air movement to keep a glider aloft. I reflect upon the dubious economics and ask him point-blank why anybody would buy an electric airplane.
“Stupidity,” he laughs. “It’s just like a hybrid car. You can’t justify a hybrid car economically. You never get the price differential back. Just pump gasoline—there’s nothing better!”
Obviously, he’s kidding. For Buck and Cole and Fishman and others like them, there’s more to it than just a bad bargain. It’s more like a love affair. And if they can fall in love with an idea like this, other people can too. There has to be a reason why, when I’m back in Los Angeles and driving home from the airport, it seems as if every other car I see is a Toyota Prius.