Piloted by project chairman Bertrand Piccard and co-founder CEO Andre Borschberg Solar Impulse Si2 completed its 62 hour long around 4000 km journey on April 23, 2016 without any fuel, powered just by solar panels. Si2 began its journey on April 21, 2016 from Kalaeloa, Hawaii and finally ended it by landing at Monfett Airfield, in the Silicon Valley of California.
There was a nine month break before Solar Impulse could resume its flight, when the planes batteries were damaged because of overheating after a flight of more than 117 hours from Nagoya, Japan to Hawaii.
The project is not only about a solar plane but also about how humans can sustain efficiently for at least five days in this type of plane Piccard and Borschberg took turns to fly the plane and used heating packs to cook their ready to eat meals and warm their shoes and gloves. The Swiss pilots began their epic world journey last year early March from Abu Dhabi, stopping in Oman, China, Japan, Myanmar and China. According to the pilots, the most risky parts to fly were the Trans-Pacific legs as there was no place to land in case of emergencies.
The propeller and batteries of the plane are powered by 17,240 solar cells present on its wings. The wings of Si2 are wider than the wings of Boeing 747. The aircraft weighs around 5000 pounds and its flight speed is around 28 mph although it doubles its speed when the sun is shining bright during the day. The plane uses the stored energy to run at night.
Si2 is to make three more stoppages in USA before it can cross Atlantic Ocean to either Europe or Northern Africa.
Twenty years from now the concept of electrical planes might be boring but for now a plane which yields its own energy with the sun is pretty exciting.