An aircraft fuelled solely on solar power completed the 16th and penultimate leg of its round-the-world journey when it landed in Cairo. The Solar Impulse 2 (Si2) landed in Egypt after flying for two days and two nights without fuel. This flight crossed the Mediterranean Sea from west to east and covered a distance of 3,745km powered only by the sun. The goal of which is to demonstrate how modern clean technologies can achieve the impossible.
The aircraft is a single-seat monoplane powered by photovoltaic cells. 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 diurnal solar cycle, including nearly nine hours of night flying, in a 26-hour flight.
The second aircraft completed in 2014 and named Solar Impulse 2, carries more solar cells and more powerful motors, among other improvements. Its wingspan is 71.9 m. It features a non-pressurised cockpit, advanced avionics, including an autopilot to allow for multi-day transcontinental and trans-oceanic flights. Supplemental oxygen and various other environmental support systems allow the pilot to cruise up to an altitude of 12,000m.The top of the wings, fuselage and tail-plane are covered by 17,248 photovoltaic cells, which power four electric motors and four 41 kWh lithium-ion batteries.
Solar Impulse is a Swiss long-range experimental solar-powered aircraft project, and also the name of the project’s two operational aircraft. It is privately-financed and led by Borschberg and psychiatrist and aeronaut, Bertrand Piccard.