The solar plane has left Seville in Spain. Its next stop is Cairo, on a flight that is expected to take 50 hours. From Cairo, there will be only one more leg to Dubai - then the sun-powered world tour will be completed.
For pilot André Borschberg, this is already his last leg in the cockpit: On Monday at 6:20 a.m. local time he took off from the Spanish airport of Seville. He is scheduled to arrive in the Egyptian capital Cairo on Wednesday morning at 9:40 a.m. local time.
The last and 17th stage of the world tour will then take Solar Impulse 2 back to Dubai in the United Arab Emirates.
That's where Borschberg started the Solar Impulse 2 adventure on March 9, 2015. Borschberg's colleague and co-pilot Bertrand Piccard will fly the plane on that final leg. Borschberg and Piccard took turns over the entire tour.
Huge bird with a tiny cabin
Even though Solar Impulse 2 has a wing span that equals that of a jumbo jet, the plane only has one seat. It can only reach speeds of 40 to 100 kilometers per hour (25 to 65 miles per hour).
Over the course of their world tour, the two adventurers have already broken numerous records. In the class of solar-powered planes, they reached a record distance of 7,212 kilometers (or 4,481 miles) of uninterrupted flight, when Solar Impulse was traveling from Japan to Hawaii.
Nearly five continuous days in the air
For the longest uninterrupted flight, the solar airplane holds the absolute record among all kinds of airplanes. During the Pacific crossing, Solar Impulse was airborne for 4 days, 21 hours and 52 minutes.
Next stop: Cairo. Bertrand Piccard will take over the Cockpit there - for the final stage of the flight
After that, the Solar Impulse 2 had to take an unscheduled break. On its way to Hawaii, the plane's batteries overheated, and needed to be replaced with an improved model.
Engineers needed to do some fast developing and building. As a result, Solar Impulse was unable to fly between July 2015 and April 2016.