Solar Impulse 2 sets off on final leg of round-the-world trip
(CNN) -- The end is in sight. Solar-powered Solar Impulse 2 took off from Cairo early Sunday on the final leg of its global tour -- the first time in history an aircraft of its kind has achieved a round-the-world flight using no fuel. The plane is en route to Abu Dhabi in the United Arab Emirates, where its epic journey originated over a year ago.