Solar Impulse 2 takes off the final leg of its round-the-world flight

In the wee hours of the morning, the Solar Impulse 2 took from Cairo, embarking on the last leg of its round-the-world journey. The 17^th and final part of the trip is set to end in Abu Dhabi, where it first set off from in March 2015.

The last leg of the journey is anticipated to take around 48 hours, at which point pilots Bertrand Piccard and Andre Borschberg will have flown a total of 21,748 miles, marking the first such journey for an aircraft of its kind.

BREAKING @bertrandpiccard has taken off from #Cairo for the last flight of the journey to #AbuDhabi #futureisclean pic.twitter.com/2ufDjAS5VK

— Solar Impulse Foundation (@solarimpulse) July 23, 2016

Of course, the plane and its pilots are already in the record books a few times over, having secured the record for the longest solo flight (from Japan to Hawaii) and crossed the Atlantic, both fuel-free.

The pilots anticipate relatively smooth sailing as Piccard takes control one final time. Though, according to the BBC, the hot, thin air above the region could pose some troubles to the solar plane’s motors. A series of delays have pushed back the flight over the year, including, most recently, a bout with an upset stomach that delay the initial July 18^th takeoff of this last leg.