Email from Hollister

Hi Michael,

I just watched the video of the team’s return to Slovenia. It was an astounding contrast to my visit to them in Hollister. I was there for for the last flight of the twin Taurus G4. There was just me – no other visitors – they had just won the prize and there was no one there but me.

I was at the last big National Air Race in Cleveland, 1947, maybe. There were several hundred thousand spectators there. What a contrast!

I have no idea how disruptive electric propelled flight will be, but surely it interests more than just me.

Congratulations to the team! They’ve shown they can do things none of the other 7 billion folks in the world can do!

Sincerely, Bob Lockhart

Green Flight Challenge Final Results

Green Flight Challenge Final Results
by DEAN SIGLER on 10/13/2011 from the CAFE website

Steve Williams, CAFE Foundation board member and e-totalizer guru, released the final results for the NASA Green Flight Challenge sponsored by Google, held at the Charles M. Schulz Sonoma County Airport from September 25 through October 1, 2011. Figures show a profound difference between the two electric winners and the two gas-powered and hybrid runners-up.

All competitors flew extremely clean motorgliders with demonstrated lift-to-drag ratios between 25:1 and 35:1. Possible explanations for the large differences in energy use include low cooling drag for electric aircraft and the efficiency of electric motors – but the differences are still surprising.

Note that a little over 11 US gallons of gasoline (energy equivalent) were used to fly seven people (Embry Riddle’s Eco-Eagle flew with only one pilot) over a total of 725.5 miles (Embry Riddle flew a shorter total distance on both “runs”). This is an enormous achievement for all concerned and a significant increase in efficiency over even the best general aviation craft available today.

Congratulations are in order for everyone who participated in making this event a grand success.

NASA Adds Some Numbers to Green Flight Challenge

NASA Adds Some Numbers to Green Flight Challenge
by DEAN SIGLER on 10/11/2011 – From the CAFE Blog website

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, while traveling at over twice the speed.”

More efficient than a Dreamliner? Pipistrel G4 takes off. Photo: NASA/Bill Ingalls

Part of this efficiency came about because of inspired design. NASA explains, “The Taurus G4 used a multi-body concept (reminiscent of the twin Mustang, or an inverse P-38); this accomplished a 61% useful load fraction (or empty weight fraction of 39%). This spanloading structural benefit is similar to that accomplished by the NASA Hybrid Wing Body concept. The Taurus G4 also achieved a motor/controller efficiency of 96%, and utilized the largest battery pack ever assembled for auto or aviation use of 100 kWhr (kilowatt hours), which included a 30 minute reserve capacity.”

Although the two more conventionally powered competitors were highly efficient designs, “neither of these aircraft met the minimum threshold of 200 pax mpg to be awarded prize funds.”

Despite the limitations imposed by current battery technology, the winning electric aircraft show what can be achieved – and it is formidable. A big thank you to NASA, Google, and the CAFE Foundation volunteers for making this event possible.

Pipistrel Taurus G4 Wins NASA Green Flight Challenge 2011
Jack Langelaan and Team Pipistrel were awarded a 3-foot-tall sculpted trophy from CAFE Foundation along with more than $1 million for winning the NASA Green Flight Challenge.

October 3, 2011 – Team Pipistrel along with partners at Penn State were announced today as the winners of the NASA Green Flight Challenge during a ceremony at NASA Ames Research Center in California. Team Pipistrel, flying the Taurus G4, was able to achieve an efficiency rating of 403.5 passenger miles per gallon. The second-place finisher e-Genius achieved 375.8 passenger miles per gallon, which is far more than the 200-mile standard required for the contest. In announcing the prize, Joe Parrish of NASA said the competition aircraft are five to 10 times more efficient that normal aircraft, emphasizing that existing aircraft could not achieve this efficiency and “innovation was required.”

Of the $1.65 million dollars available from NASA, Team Pipistrel was awarded $1.35 million and e-Genius $120,000. Dr. Brian Seeley, president of the CAFE Foundation, said of the competition, “Our vision is to bring forth future air vehicles that are emission-free, safe, and can land anywhere – to basically do what birds do.” Seeley also called EAA Chapter 124 member volunteers the “backbone” of the event, which took place at Sonoma County Airport in California.

In accepting the prize money, Team Pipistrel leader Jack Langelaan said, “This has been incredible progress over three years. Together we have seen that electric power is a beautiful way to power airplanes. It only costs $7 to fly the Pipistrel for two hours compared to the much higher cost to use fossil fuels.” Langelaan finished his remarks with a bold prediction: “We will go from battery-powered flight to supersonic electric flight in one decade.”
It “flies like it looks,” said pilot Dave Morss, EAA, “A little odd, you’re off the centerline of the aircraft and in the arc of a curved wing – sitting in a 4 1/4 degree bank.”

It was a smooth competition for Team Pipistrel with only a flat tire taxiing out, but the team had a spare on hand and changed it out very quickly. Morss reports that the G4 stalls at less than 52 mph, and is very benign in the stall. For the first 15 to 20 flights they landed at 60 mph, but they now land a little faster to make the landing easier since there’s no suspension on the landing gear.

The winner of the NASA Green Flight Challenge was announced Monday during the Green Flight Expo at NASA Ames Research Center at Moffet Field. Google, which has been doing extensive research with electric cars, sponsored the first-ever electric aircraft charging station, which supplies electricity from geo-thermal energy, as well as other portions of the event.

Dave “Batman” Morss kicks back in the Pipistrel Taurus G4 with Sport Aviation during the battery run-down test.

Besides the top two finishers, which were electric aircraft, the Rotax-powered Phoenix competed in the event and was the only aircraft to fly in by itself. Embry-Riddle’s EcoEagle participated as an exhibition contestant. The competition wrapped up Thursday with a final weigh-in for gas-powered aircraft and a battery run-down test for the electric aircraft. The electric aircraft needed to show a 1/2-hour reserve and each aircraft was ground-run at half throttle to demonstrate this requirement.

Another New Pipistrel
The effort to win the NASA competition has delayed progress a few months on a new aircraft being developed by Pipistrel, the four-place Panther, according to Tine Tomazic, a technical coordinator for Pipistrel’s research and development section.

The company is building two aircraft, one with piston power, the other with electric, aiming for first flights early in 2012 prior to display at AERO Friedrichshafen. Pipistrel has placed a high priority on bringing the Panther to Oshkosh but have not decided if the Taurus G4 will make the trip as well.

Professor wins lofty award: Electric plane soars past fuel efficiency expectations

Team Lead Jack Langelaan poses for a photograph next to the Pipistrel-USA, Taurus G4, aircraft prior to winning the 2011 Green Flight Challenge, sponsored by Google, on Monday, Oct. 3, 2011 at the NASA Ames Research Center, Mountain View, Calif. The all electric Taurus G4 aircraft achieved the equivalency of more than 400 miles per gallon. NASA and CAFE held the challenge to advance technologies in fuel efficiency and reduced emissions with cleaner renewable fuels and electric aircraft.

Penn State professor Jack Langelaan’s mil-lion- dollar dream took flight in the clear blue skies above California last week.
Over the course of four days in late September, the strange-looking Pipistrel electric plane Langelaan and his team had spent almost two years perfecting far exceeded lofty speed and fuel efficiency standards to win NASA’s Green Flight Challenge and a $1.35 million prize — one of the highest purses ever awarded for a flight competition.
The Green Flight Challenge was created two years ago, through NASA’s Centennial Challenges program, as a way of spurring private companies to develop a highly fuel-efficient small airplane. Funded by Congress and additionally sponsored by Google, the challenge required the winning aircraft to fly 200 miles in less than two hours and use less than one gallon of fuel per occupant, or the equivalent in electricity, with a minimum of two occupants.
The goal facing the 14 teams that initially entered the contest was so audacious that the NASA administrator overseeing the contest did not think it could be met.
“Everybody thought, when (this challenge) was first put out there, that it was not likely to be achieved on the first go-round,” said Larry Cooper, the program executive for the Centennial Challenges.
When Langelaan, an assistant professor of aeronautical engineering and State College resident, first heard about the program, he was instantly smitten.
“I immediately started doing back-of-the-envelope calculations about whether the goal was even feasible,” he said. “I realized it was possible, but I had to find the right airplane to start with.”
Langelaan made a trek to Wisconsin’s Oshkosh Air Show in the summer of 2010 specifically to meet the management team of Pipistrel, a tiny Slovenian company specializing in electric-powered planes, one of which — the Taurus — Langelaan was particularly eyeing.
Langelaan cornered Ivo Boscarol, Pipistrel’s CEO, and launched into a passionate pitch. It took a few months, but Boscarol finally agreed, and Langelaan was named team leader.
Members of the Pipistrel team got to work solving the complex engineering and design issues they faced. Between December 2010 and the competition’s start in September, the team spent about $1.5 million and “countless” man-hours to design and build the plane, Langelaan said.
“Even with winning the prize, we didn’t even break even with our investment, so it shows you that taxpayers are really getting money’s worth out of these competitions,” he said.
The Pipistrel team worked furiously to get the plane ready. It was assembled in Pennsylvania, and early testing took place in Mifflin County. Langelaan, who was tasked with putting together the flight plan, hit the books. He relied on models provided by Penn State’s meteorology department for local wind conditions in California to arrive at the optimum settings for the plane’s flight.
The short time frame between the announcement of the competition and its start prompted most of the competition to bow out. Pipistrel was one of only four of the original 14 entrants to actually make it to the Moffett Field starting line, at NASA’s Ames Research Center in Santa Rosa, Calif., on Sept. 26.
With top professional pilots lined up for the test flights, initial inspections disqualified two more teams before the planes even left the ground.
The first day’s trial required the Pipistrel plane to clear a 50-foot barrier soon after takeoff and do so with a nearly silent engine. The white rectangle of the dual-cockpit Taurus cleared the hurdle and the noise requirement, as did its sole competition, the e-Genius team.
Over the next three days, both teams dueled, finishing remarkably close to one another in each challenge. On the second day, the planes had to fly four cycles of a closed-loop course with an average speed of at least 100 mph and use the energy equivalent of less than one gallon of fuel per passenger.
On the final day of competition, the planes flew another 200 miles, with the objective of flying at top speed while maintaining energy efficiency of at least 200 passenger miles per gallon. They also both had to demonstrate that they had a 30-minute fuel reserve after landing. Once again, both Pipistrel and e-Genius finished so close together that it was impossible to tell who had won. The teams had to wait until the tension-fraught award ceremony on Monday to find out who had come out on top.
In the end, the Pipistrel team was declared the victor, having far exceeded all the base requirements of the challenge — traveling the equivalent of more than 400 passenger miles per gallon of aviation fuel — a figure that just bested the e-Genius team in energy efficiency.
“It was pretty cool to hold a $1.35 million check,” Langelaan said. “But it was even cooler to work with such a dedicated team of people. To witness the level of professionalism and talent of the team, and to see it all working for one goal and the amount of trust we all had in each other, was incredible.”
Langelaan, who had two grad students help on the project, said his share of the prize money will go to fund his research. But the impact of the competition will be more far-reaching than that, NASA’s Cooper said.
“The Pipistrel team has obviously demonstrated something here that people are sitting up and taking notice of,” he said. “Two years ago, no one ever thought it was possible to fly a plane with this kind of efficiency. Pipistrel and e-Genius both have an interest in taking these technologies and putting them into commercially available products, which will initially be smaller planes. But later on, I’m positive we’ll see some of this stuff move into other aircraft. As the battery technology improves, it will move into larger and larger vehicles.”
Such a move will help aviators, who could fly the same distance in the Pipistrel plane for $7 in energy costs that it now takes $60 worth of gasoline to travel.
“What Pipistrel’s done, that’s kind of like doubling the fuel efficiency of what you’d be able to do if you were able to fly a Prius,” Cooper said.

Read more: