{"id":994,"date":"2010-05-29T22:52:20","date_gmt":"2010-05-30T05:52:20","guid":{"rendered":"http:\/\/cafe.foundation\/blog\/?p=994"},"modified":"2010-05-29T22:52:21","modified_gmt":"2010-05-30T05:52:21","slug":"the-electric-powered-aircraft-a-sequel","status":"publish","type":"post","link":"http:\/\/cafe.foundation\/blog\/the-electric-powered-aircraft-a-sequel\/","title":{"rendered":"The Electric-Powered Aircraft, A Sequel"},"content":{"rendered":"

David Ullman, a professor at Oregon State University in Corvallis, Oregon, author, \u00a0and owner of his own consulting firm, Robust Decisions, has published part two of his article,\u00a0“The Electric Powered Aircraft,”\u00a0that first appeared in Kitplanes’ <\/em>October 2009 issue (see our October 18, 2009 entry, “Hear the Hum?\u00a0 Kitplanes Does”)\u00a0.\u00a0 You won’t have to rush to the nearest bookstore for the sequel, since this is online in the Experimental Aircraft Association’s Experimenter<\/a><\/em>.\u00a0<\/p>\n

A great deal of the Experimenter <\/em>is fired up with speculation and skepticism about electric aircraft and their feasibility in the current issue, including an editorial <\/a>by Patrick Panzera, long-time engine guru and editor of the e-zine.\u00a0 A great many of the readers’ comments have a “not ready for prime time” content, indicating that the writers don’t see electric aircraft as a practical reality any time soon.\u00a0 Despite Panzera’s\u00a0guarded enthusiasm for electric craft (he attended EAS IV), others have more moderated views.\u00a0<\/p>\n

One notes, “I\u2019m afraid that electric flight (even though an electric drive system will weigh less than a typical avgas firewall-forward complete package) will not be practical until they are powered by fuel cells capable of extracting as much chemical energy from fuel as exists in gasoline. And this probably won\u2019t solve the carbon footprint problem, as energy-efficient fuel cells will most likely use hydrocarbon fuels.”<\/p>\n

Another attempted to talk Panzera from attending the Symposium.\u00a0\u00a0<\/p>\n

“Electric flight won\u2019t work because it can\u2019t<\/em> work \u2013 the basic physics and chemistry are against it. The ‘energy density’ of any plausible combination of battery chemicals is just too low.\u00a0<\/p>\n

“That\u2019s not to say there will never be a battery-powered plane,\u00a0but they will never compete with a combustion engine.”<\/p>\n

Ullman, in his article, is more optimistic, predicting the following by 2015:<\/p>\n

  • “An electrically powered airplane will stay aloft for two hours carrying two people.<\/li>\n
  • “An electrically powered airplane will be cost competitive for light-sport aircraft and trainers.<\/li>\n
  • “Electric airplanes will be powered by batteries with energy densities at least 50 percent better than those available today.<\/li>\n
  • “An electric airplane will land at an airport near you!”<\/li>\n

    Although he wrote those words over seven months ago, Ullman’s predictions seem like safe bets in the wake of EAS IV.\u00a0\u00a0 The majority of the article is an excellent primer on motors, controllers, batteries and battery management systems.\u00a0 Considering the eventual reduction in battery size and weight likely to come, Ullman even hypothesizes an electric DC-3 – an AC\/DC-3!<\/p>\n

    To show that Ullman is not just just a University theorist, here is his nearly completed Velocity, obviously bursting with the need to escape its garage hangar.<\/p>\n

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    David Ullman's Velocity, yearning to breath free<\/p><\/div>\n