Solar Impulse 2 just became the first plane to make a round-the-world trip with zero oil http://cnn.it/2aekh1y | CNN International

#Si2 flew over the Bay Area & #SanFrancisco for 3 hours today. Follow the landing LIVE on solarimpulse.com | Climate Impulse

the legacy of Solar Impulse 2 (Si2) has evolved from a singular record-breaking flight into the blueprint for a new generation of "perpetual" aircraft. In 2016, this Swiss-engineered marvel completed a grueling 40,000-kilometer circumnavigation of the globe without using a single drop of liquid fuel, proving that clean technology could sustain long-duration flight across oceans and continents alike. The aircraft featured a wingspan of 72 meters (wider than a Boeing 747) but weighed only 2.3 metr