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.

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