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A solar-powered airplane that landed in Arizona last week after a daylong flight from California is now headed to Oklahoma on the latest leg of its around-the-world journey.

The file photo shows the two pilots of the Swiss-made Solar Impulse 2 in front of the airplane.

The Swiss-made Solar Impulse 2 took off from Phoenix Goodyear Airport at 3am local time with a destination of Tulsa International Airport.

The globe-circling voyage began in March 2015 from Abu Dhabi, the capital of the United Arab Emirates, and made stops in Oman, Myanmar, China and Japan.

After Oklahoma, the plane is expected to make at least one more stop in the United States before crossing the Atlantic Ocean to Europe or northern Africa.