The Swiss-built Solar Impulse airplane ended its two-month-long, solar-powered trip across America with a nail-biter of a flight from Washington to New York on Saturday.
"Maybe if I didn't have 10 cameras pointed at me, I would cry," Swiss adventurer Bertrand Piccard, one of the pilots for the coast-to-coast journey, said just before the 11:09 p.m. ET landing at New York City's John F. Kennedy International Airport.
The extra drama came from the discovery in the trip's final hours that the ultra-light airplane had suffered an 8-foot-long (2.5-meter-long) tear in the fabric on the lower side of the left wing. Andre Borschberg, who was filling the pilot's seat for the Washington-to-New York segment of the "Across America" journey, noticed a balance issue with the wings on Saturday afternoon — and pictures taken by a helicopter flying nearby confirmed the damage.
Neither Borschberg nor the plane were thought to be in danger; nevertheless, the Solar Impulse team did everything it could to reduce the risk. That meant considering all the options for ending the flight, including the possibility of bailing out over the Atlantic. It meant passing up a Statue of Liberty photo op and working out a deal with air traffic controllers to land the plane three hours earlier than originally planned. And it meant changing the landing procedure.
Borschberg brought the airplane in low and slow, without air braking, to reduce the stress on the wing. The spindly craft seemed to float to a stop on the runway — prompting cheers at JFK as well as at Solar Impulse's mission control center in Switzerland. Moments later, a stepladder was set up so that Piccard could greet Borschberg in the cockpit. And despite what he said, Piccard could be seen wiping at his eyes after the two men hugged.
"It was supposed to be the shortest and easiest leg," Piccard said later. "It was the most difficult one."
Early takeoff, late landing
The "Across America" odyssey began on May 3 with a flight from Moffett Field, near San Francisco, to Phoenix, and continued with hops to Dallas-Fort Worth, St. Louis, Cincinnati and Washington. Piccard and Borschberg, co-founders of the Solar Impulse venture, traded turns piloting the single-seat plane. For most of those flights, the plane had to leave early and wait until late to land, so as to reduce the potential for disrupting commercial air traffic.
Saturday's trip began with a 4:46 a.m. ET takeoff from Washington's Dulles International Airport. The solar-powered plane's top speed is around 45 mph (72 kilometers per hour), but even at that speed, there were plenty of hours to spare for the 228-mile (336-kilometer) trip.
While Borschberg flew in circles off the coast of New Jersey, waiting for clearance to land, he participated in media interviews and a video hangout with such luminaries as James Cameron, the famed film director and ocean explorer; and Erik Lindbergh, the grandson of aviation pioneer Charles Lindbergh.
Before the wing's damage came to light, Borschberg also had time to reflect on the meaning of Solar Impulse's odyssey: Swiss corporate backers have put up €90 million ($115 million) over the past decade for the project, which is aimed at demonstrating technologies ranging from solar-power generation and storage to ultra-light composite materials.
Powered by light
Solar Impulse weighs as much as an automobile, but has the wingspan of a Boeing 747 jumbo jet. Scooter-type electric motors drive the single-seat plane's propellers. All of the power comes from almost 12,000 solar cells installed on its wings and horizontal stabilizer. Excess electricity is stored in 800 pounds' (363 kilograms') worth of batteries, so the plane can theoretically fly day and night.
"We have an airplane which has almost unlimited endurance," Borschberg told NBC News. "This airplane could have flown directly from California to New York, so it’s fully sustainable in terms of energy. The limiting factor is the pilot."
Piccard is already in the record books for the first-ever nonstop balloon flight around the world in 1999 (which he flew along with Brian Jones). He and Borschberg have been flying the Solar Impulse prototype in Europe and Africa over the past couple of years, but with the end of the "Across America" trip, this particular prototype will be retired. A more advanced solar-powered plane is being built for an even more ambitious series of flights around the world in 2015.
Clean tech on the ground
Piccard has said that solar-powered planes could conceivably go commercial within five years or so, but Borschberg emphasized the potential applications for clean-energy technologies on the ground.
"All the partners who are involved with this project developed technologies not for the aviation world, but for their own customers," Borschberg told NBC News. "The customers are maybe homebuilding, maybe the automobile industry, maybe appliances. That’s what they are looking for, and that’s what’s slowly taking place. So if part of the legacy could be to show a way how to increase the efficiency of what we do and reduce the energy consumption but keeping the same quality of life, that would be a wonderful achievement for the project."
Cameron, who is as proud of his ocean adventures as he is of his blockbuster films "Titanic" and "Avatar," paid tribute to Borschberg and Piccard during Saturday's Google+ Hangout.
"What Solar Impulse stands for is renewable energy — not just electric aircraft, but use of solar power in general, and this is something that’s going to be fundamental and critical to the survival of the human race," Cameron said. "You've got people that are standing for something, committing themselves, putting their personal asses on the line to make a point for the betterment of human civilization, and I greatly applaud that."
The consciousness-raising is due to continue after Saturday night's landing: Borschberg and Piccard will participate in a NASDAQ opening-bell ceremony and are to meet with U.N. Secretary General Ban-Ki Moon on Tuesday.
More about the Solar Impulse odyssey:
- First-ever 'pit stop' for Solar Impulse
- Solar-powered plane takes shelter
- Distance record set for solar-powered flight
Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the NBC News Science Facebook page, following@b0yle on Twitter and adding +Alan Boyle to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.