After a slow-speed, 19-hour flight the Solar Impulse airplane landed safely early Saturday morning in Phoenix, Ariz, completing the first leg of a historic transcontinental airplane trip using zero fossil fuels.
The plane took off at 6:12 a.m. Local time and arrived at Phoenix's Sky Harbor airport Saturday at 12:30 a.m. The plane won't be setting any records for air speed; it can only fly at an average of 43 mph.
But the mission to fly across America in an airplane using only the Sun's energy is a worthy record of its own.
Of Swiss design, the Solar Impulse project is intended to show the world what can be done with clean energy technology like solar power. The single-seater airplane weighs about as much as a car and has the wingspan of a Boeing 747, plenty of room to house the aircraft's 12,000 solar cells.
By day, the solar cells power plane's electric motors while also charging batteries, meaning Solar Impulse - unlike other solar-powered aircraft - can fly at night. It flew in darkness for several hours on the first stage of the journey.
For the first of the five-stage journey, the plane was flown by Bertrand Piccard, the Swiss psychiatrist and adventurer who was the first to complete a non-stop, around-the-world balloon flight. Piccard will alternate cockpit time with co-pilot Andre Borschberg, who is also co-founder of the project.
One goal of the Solar Impulse is to fuel a conversation about how the world will meet its goal of reducing CO2 emissions. The project website also states Solar Impulse will tackle the problem of resistance to change, which risks locking society into "dangerous" and "costly" old habits.
"Our airplane is not designed to carry passengers, but to carry a message," Piccard said on the project's webpage.
In 2010 the Solar Impulse successfully completed a 26-hour overnight flight, and later a flight from Switzerland to Morocco in 2012. The project's eventual goal is an around-the-world trip in the solar powered plane.
Borschberg echoed the spirit of the first pioneers of transcontinental flight when talking about the future of solar flight.
"You should see this like being in 1915 when the pioneers were trying to do these first cross-country flights - still unable to cross the ocean, but an important step for the development of aviation," Borschberg said, according to the BBC.
The next leg of the journey will be from Phoenix to Dallas, Texas.