Solar plane pauses in Bay Area as it soars above past records

The Solar Impulse 2 recharges in a portable hangar. The Solar Impulse 2 recharges in a portable hangar. Photo: Brittany Murphy, The Chronicle Buy photo Photo: Brittany Murphy, The Chronicle Image 1 of / 44 Caption Close Solar plane pauses in Bay Area as it soars above past records 1 / 44 Back to Gallery

Silicon Valley has birthed its share of cutting-edge creations and played host to a range of technological firsts, but an airplane with wings rivaling the span of a soccer field still evoked awe Sunday.

The plane looks a lot like something out of a toy-store kit, with long wings and a skinny body, the long-glider kind launched from pinched fingers. The Solar Impulse 2 is a lot bigger, with with a 236-foot wingspan and an array of solar panels that are carrying it around the world without fuel. It arrived in California Saturday night after a 62-hour flight from Hawaii.

The Solar Impulse 2 plane and its two pilots, Bertrand Piccard and André Borschberg, are breaking several world records in the process, including longest endurance flight by a solo pilot in any kind of plane and the first solar flight across the Pacific Ocean.

The effort, sponsored by Google, watchmaker Omega and robotics-focused ABB, among others, is about not only adventure and unparalleled achievement, but also the environment.

“For hundreds of years people ... were coming with boats to find freedom in America,” Piccard said Sunday at Moffett Field in Mountain View, where the plane sits waiting to start the next leg of its journey. “And now I am arriving in the first solar-powered airplane that crossed the Pacific. Freedom is not only anymore a country. Freedom is a state of mind toward energy. Freedom is solar power. Freedom is clean technologies when you don’t need to fight for oil.”

“We were told by the aviation world that it’s impossible to build such an aircraft,” added Borschberg. “For us, it’s a demonstration of how to make the impossible possible. And I think it’s an inspiration people need today.”

The plane has a cruising speed of 28 to about 50 mph and a maximum altitude of 28,000 feet. It’s powered by 17,248 solar cells built into the wings, panels that send power into four batteries, storing energy so the plane can fly through the night.

And it’s lightweight at 5,100 pounds, or about that of an empty family car, according to the Solar Impulse team.

The plane took off from Abu Dhabi in March 2015, the start of the planned 35,000-kilometer journey to Oman, Indian, Myanmar, China, Japan, Hawaii, across the United States, across the Atlantic to Europe, and then back to Abu Dhabi.

The trip was delayed in Hawaii, after the batteries overheated on the five-day flight from Japan in July. The time-consuming repairs, a delay that pushed the team past the good-weather window, meant the plane had to wait out winter on Oahu.

The Solar Impact 2 took off from Hawaii on Thursday, piloted by Piccard, and arrived at Moffett Field — after a Golden Gate Bridge fly-by — Saturday night. He had been in the unpressurized and unheated, 3.8-meter cockpit for 2½ days.

Piccard described living in the plane for days on end. When the sun comes up, he eats breakfast, brushes his teeth and uses the bathroom. As the sun rises, the plane climbs in altitude. He has to wear an oxygen mask, which makes it difficult to eat, because an alarm starts ringing every time he removes the mask.

With the higher altitude, he puts on warmer clothing, although only the gloves and shoes are heated because it would take too much energy to warm anything else. At all times, he is wearing a harness with a parachute and a life vest.

At night, he and Borschberg are allowed to sleep only 20 minutes at a time so they can monitor the plane. If all goes well, they sleep for 20 minutes, wake up for a minute, and go back to sleep. That happens about 10 times during the course of the night.

The pilots will fly across the United States to New York, with a potential stop in Phoenix, as they make their way back to Abu Dhabi. They will leave no earlier than Wednesday due to weather conditions. The plane is not open for viewing to the public.

Asked whether he believed the plane would complete its world tour, Piccard said, “I hope it will work. You never know. It is an adventure, not a business plan.”

Emily Green and Jill Tucker are San Francisco Chronicle staff writers. Email: egreen@sfchronicle.com, jtucker@sfchronicle.com Twitter: @jilltucker