The Solar Impulse 2 solar-powered airplane began the last leg of its around-the-world flight early Sunday.
Pilot Bertrand Piccard and the plane took off from Cairo en route to Abu Dhabi. Mission control said Solar Impulse 2 is expected to land in Abu Dhabi after a 48-hour flight.
The attempt to fly around the world began in Abu Dhabi in March of 2015. It landed in Tulsa on May 12, on a leg that had begun in Phoenix. Stormy weather kept it on the ground here longer than planned and it didn't leave Tulsa until May 21, 2016.
Solar Impulse 2 uses solar and battery power to power its four motors. The plane weighs about the same as a small car but has a huge and relatively delicate wing, so mission control has to carefully plot its course away from unstable weather conditions.
Piccard said he's been dreaming of completing an around-the-world flight since 1999.
The airplane's ideal speed is about 28 miles per hour. Piccard took turns flying the plane with Andre Borschberg. They made stops in Oman, Myanmar, China, Japan and Hawaii before crossing the U.S. this summer.