Solar Impulse 2 took off early Sunday for Abu Dhabi on the 17th and last leg of its around-the-world journey, after an unexpected delay in Cairo due to bad weather.
The solar-powered aircraft took off from Cairo about 1:30 am (2330 GMT Saturday), a half hour behind schedule on its two-day non-stop flight to the capital of the United Arab Emirates.
The carbon-fibre aircraft, which has a wingspan of 72 metres, began its attempt to become the first solar-powered plane to fly around the globe in March 2015 from Abu Dhabi.
The zero-fuel plane, which is meant to draw attention to the potential of renewable energy, arrived on July 13 in Cairo from Seville, Spain, after a two-day flight across the Mediterranean Sea and over the ancient pyramids.
Solar Impulse 2 on June 23 became the first solar-powered aircraft to cross the Atlantic Ocean, flying 70 hours from New York to Seville.