With the whine of electric motors, Solar Impulse 2 has begun the penultimate leg of its round-the-world flight. Today at 9:22 pm PDT (4:22 GMT), the single-seater, solar-powered aircraft took off in the predawn darkness from Seville, Spain on course for Cairo, Egypt, with pilot André Borschberg at the controls.

The takeoff from Seville International Airport will be the last flight for Borschberg on Solar Impulse 2 as he hands over command to alternate pilot Bertrand Piccard, who will conduct the last flight to the finish line in Abu Dhabi.

Today's takeoff is the beginning of the 16th leg of Solar Impulse 2's attempt to circumnavigate the world entirely on solar power, which began in March 2015. The previous flight took the experimental aircraft from JFK airport in the United States to Seville for the first solar-powered transatlantic flight after bad weather prevented landing at the primary destination of Paris.

According to Solar Impulse, Borschberg will fly over the Mediterranean Sea, including the airspaces of Tunisia, Algeria, Malta, Italy, and Greece, before reaching Egypt. The estimated flight time is 50 hours and 30 minutes.

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