How Green was GFC Electricity?

Dean Sigler Diesel Powerplants, Electric Powerplants, GFC, Sustainable Aviation 2 Comments

The blog received several comments about the relative energy use of electric aircraft, and how NASA and the CAFE Foundation might have overstated the efficiency and low emissions for the electric aircraft in the competition. Reader Robert Swanson thought the conversion between kilowatt hours and gasoline created a discrepancy. “The discrepancy in performance of gasoline and electric powered aircraft is due to an absurd conversion factor between kWh and gallons of gasoline.  The conversion should be calculated from the number of gallons of gasoline consumed by the engine driving the generator used to charge the batteries.” Steven Crow added this objection.  “Even after reading the relevant pdf’s, it is far from clear to me how CAFE computed ‘mileage’ for the …

NASA Adds Some Numbers to Green Flight Challenge

Dean Sigler Electric Powerplants, GFC, Sustainable Aviation 0 Comments

NASA’s Mark Moore sends this link to NASA’s press release on the recent NASA Centennial Challenge Green Flight Challenge sponsored by Google.  The CAFE Foundation organized and managed the event. “Today we’ve shown that electric aircraft have moved beyond science fiction and are now in the realm of practice.” – Chief technologist at NASA Joe Parrish. The lead quote is informative, as are some figures from the release.  “The competition resulted in the world’s most efficient aircraft, beating the state of the art of approximately 100 pmpg (passenger miles per gallon) which is achieved by the newly released Boeing 787 airliner.  Essentially this contest showed the ability of small aircraft to achieve twice the efficiency of the most efficient production automobiles today, …

Green Flight Challenge Winners

Dean Sigler Diesel Powerplants, Electric Powerplants, GFC, Sustainable Aviation 1 Comment

Monday, October 3 was the second day of Nobel Prize announcements, but also marked the Green Flight Challenge Expo, sponsored by Google and staged under the control tower on Moffett Field, home of NASA Ames Research Center, Mountain View, California. The four airplanes that flew in the Challenge at Charles M. Schulz Sonoma Country Airport in Santa Rosa, California were joined by Greg Stevenson’s full-size mockup of his GFC design and a Pipistrel Virus that had won an earlier NASA/CAFE Personal Air Vehicle (PAV) Challenge.  Stevenson’s airplane was a reminder that there were numerous entrants that, for a variety of reasons, could not attend.  There is a huge number of aircraft in the wings, so to speak, that will fill these …