“Solar Impulse 2” started an “around the world” flight, with the first step of the journey being 400 km. flight down the coast of the Persian Gulf, starting from the UAE.
Solar Impulse 2 has a wingspan similar to a 747’s, but weighs just a bit more than an average, or 5,000 lb.
During the day, Solar Impulse 2 has four 17.5 horsepower engines that, when running at full speed and while gaining altitude, continuously charge its batteries along the way. It can store 165 kilowatt-hours in the batteries that are stored behind the engines. At night, the engines will run off batteries at a much slower speed, and Solar Impulse 2 will gradually glide down closer to sea level before restarting a climb the next day.