Sun powered aircraft Solar Impulse 2 has taken off from Moffett Airfield in Mountain View, near San Franciso in California, on the latest leg of its round the world flight.
The plane of Swiss pioneers Bertrand Piccard and André Borschberg set off from San Francisco bound for Phoenix Goodyear Airport in Arizona, marking the beginning of the crossing of the United States.
The flight is expected to cover the 720 miles in around 16 hours, depending on weather conditions.
The team hopes to eventually reach New York before crossing the Atlantic Ocean into Europe, and returning to Abu Dhabi, where the journey began in March last year.
The aircraft landed in Hawaii last July, but was grounded for nine months after suffering critical heat-related damage to its batteries during the previous stage of its flight.
The team resumed the mission on April 21, when co-pilot and co-founder Bertrand Piccard took off for California after repairs and test flights were completed.
The two Swiss pioneers will be relaying each other at the controls of Si2 with the objective to reach New York City as soon as possible.
“We are now continuing the adventure across the United States, with the ambition to show everyone along the way, that if an airplane can fly day and night without fuel, we could all use these same clean technologies on the ground to develop new industrial markets and stimulate economic growth, while also protecting the environment,” added Piccard.
Piccard and Borschberg are attempting the first round-the-world solar flight with no fuel to show that the world can be run on clean technologies.