Solar Impulse II gets clearance for takeoff after a three week wait, and sets off to continue its historic journey.<br /><br /> The solar powered aircraft took off from Nagoya, Japan to Hawaii on the eighth leg of its round the world voyage.<br /><br /> Bad weather had delayed departure for the longest and most risky stage of the mission.<br /><br /> .@solarimpulse is flying on 27,000 feet with a ground speed of about 80 knots http://t.co/f5c5mL9L3F<br />#futureisclean pic.twitter.com/GqIVBWJr6M— Flightradar24 (@flightradar24) June 29, 2015<br /> <br /><br /> Swiss businessman and pilot André Borschberg is aiming to fly for 5 days non-stop – he plans to practise polyphasic sleep meaning splitting up rest time into 20 minute power naps. The cockpit seat is adjustable to make it into either a bed or a yoga mat to practise poses that will improve blood circulation.<br /><br /> 17.05 UTC: the man of the moment, @andreborschberg, arriving on the runway, ready for the flight of his life! pic.twitter.com/Vh7Rdvwm96— SOLAR IMPULSE (@solarimpulse) June
