Solar Impulse

Solar Impulse is a Swiss long-range <a href="/facts/Experimental_aircraft/pxLLTsK4">experimental</a> <a href="/facts/Solar_aircraft/txU0ouMl">solar-powered aircraft</a> project, and also the name of the project's two operational aircraft. The privately financed project is led by Swiss engineer and businessman <a href="/facts/Andr%25C3%25A9_Borschberg/nxKhG9Wp">André Borschberg</a> and Swiss psychiatrist and balloonist <a href="/facts/Bertrand_Piccard/fBFrMmnl">Bertrand Piccard</a>, who co-piloted <a href="/facts/Breitling_Orbiter_3/91vmS1yX">Breitling Orbiter 3</a>, the first <a href="/facts/Balloon_(aeronautics)/athPr7Hs">balloon</a> to circle the world non-stop. The Solar Impulse project's goals were to make the first <a href="/facts/Circumnavigation/8R6vSgTM">circumnavigation</a> of the Earth by a piloted <a href="/facts/Fixed-wing_aircraft/0DQQP2rB">fixed-wing aircraft</a> using only solar power and to bring attention to <a href="/facts/Environmental_technology/3bzFoTex">clean technologies</a>.
The aircraft is a single-seated <a href="/facts/Monoplane/2fLoovyH">monoplane</a> powered by <a href="/facts/Photovoltaic_cell/3L814UCC">photovoltaic cells</a>; it is capable of taking off under its own power. The prototype, often referred to as Solar Impulse 1, was designed to remain airborne up to 36 hours. It conducted its first test flight in December 2009. In July 2010, it flew an entire <a href="/facts/Diurnal_cycle/ttuYQ6cj">diurnal solar cycle</a>, including nearly nine hours of night flying, in a 26-hour flight. Piccard and Borschberg completed successful solar-powered flights from Switzerland to Spain and then Morocco in 2012, and conducted a multi-stage flight across the US in 2013.
A second aircraft, completed in 2014 and named Solar Impulse 2, carries more solar cells and more powerful motors, among other improvements. On 9 March 2015, Piccard and Borschberg began to circumnavigate the globe with Solar Impulse 2, departing from <a href="/facts/Abu_Dhabi/0fXh0jQ2">Abu Dhabi</a> in the United Arab Emirates. The aircraft was scheduled to return to Abu Dhabi in August 2015 after a multi-stage journey around the world. By June 2015, the plane had traversed Asia, and in July 2015, it completed the <a href="/facts/Flight_endurance_record/6dCQndaw">longest</a> leg of its journey, from Japan to Hawaii. During that leg, the aircraft's batteries sustained thermal damage and took months to replace.
A battery cooling system was installed and Solar Impulse 2 resumed the circumnavigation in April 2016, when it flew on to California. It continued across the US until it reached New York City in June 2016. Later that month, the aircraft crossed the Atlantic Ocean to <a href="/facts/Seville/weWX4eIK">Seville</a>, Spain. It stopped in Egypt before returning to Abu Dhabi on 26 July 2016, more than 16 months after it had left (506 days), completing the approximately 42,000 km (26,000 mi) first circumnavigation of the Earth by a piloted fixed-wing aircraft using only solar power.
In 2019, the Solar Impulse 2 was sold to <a href="https://www.skydweller.aero/">Skydweller Aero</a>, a US-Spanish company using the airframe to develop autonomous <a href="/facts/Unmanned_aerial_vehicle/qt87T19t">unmanned aerial vehicles</a> capable of perpetual flight. It plans to use the aircraft for research and development and flight testing, after which the Solar Impulse 2 will be returned for permanent display at the <a href="/facts/Swiss_Museum_of_Transport/PcwC9q7C">Swiss Museum of Transport</a>.

Solar Impulse open-in-new

Solar Impulse