On the morning of May 31, 2015 Swiss Pilot André Borschberg took off in the single-seater solar powered aircraft from Nanjing, China bound for island state of Hawaii in the United States.

André Borschberg in front of the media before boarding Successful take off from China bound for Hawaii – Copyright Solar Impulse
This is the longest leg of Solar Impulse’s around the world journey. Reaching Hawaii will take six days and five nights (around 130 hours of flying time), covering approximately 8,172 km (5,078 miles). This is the longest distance ever attempted in a 100% solar powered aircraft.
André will spend close to a week in a 3.8m3 cockpit alone. Remaining physically and mentally alert throughout the entire journey with only short periods of sleep will be an immense challenge. The biggest concern however, will be whether the energy collected from the sun throughout the day will be sufficient to power the aircraft through the following night.
If the solar impulse round the world project is going to fail this marathon leg is where it is most likely to happen.
Weather is the real wild card. As well as sufficient sunlight the team need to hope for limited turbulence. The aircraft has the wing span of a jumbo jet but only the weight of a car. Heavy turbulence could lead to disaster.
André’s partner Bertrand Piccard beat Richard Branson to become the first to circumnavigate the globe in a hot air balloon, so the pair between themselves they have deep experience to draw on.
The synergy between André Borschberg and Bertrand Piccard is a key success factor for the project as well as a touching human story of two men with a drive to improve the state of the world environment and inspire future generations to push further forward.
“This is the moment of truth. If successful, this flight to Hawaii will demonstrate the credibility of the vision Bertrand had 16 years ago of an airplane flying for days without fuel to change our mindset regarding the enormous potential of clean technologies and renewable energies” said André before take off.
Allez! Hop!
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