Solar Impulse 2 finally resumed its circumnavigation of the globe Sunday evening, taking off from Nagoya, Japan, where it had faced numerous delays since its unscheduled landing at the beginning of the month.
According to a post on the team's official website, the solar-powered plane has already passed "the point of no return" meaning it will continue onward without the option of turning back to Japan. The total flight is expected to take some 120 hours (5 days).
Originally planning to fly all the way from China to Hawaii, the plane took off on May 31 but was forced to land in Japan due to poor weather conditions. The aircraft has remained stranded there ever since after several anticipated take offs were aborted due to weather and technical issues.
Last week, co-pilot Bertrand Piccard announced that if the plane was unable to launch soon, it would remain stranded for the winter and would only be able to continue its journey next spring. The days will soon become too short for the the aircraft to safely continue its journey.
Even though Solar Impulse 2 is successfully on its way, this will be the most challenging flight for the aircraft to date. As the only person piloting the aircraft, Borshberg will take short 20-minute power-naps throughout the multi-day journey to conserve his energy.
Borshberg also plans to use yoga and self-hypnosis, which he said would help him get the maximum rest possible during his short naps. However, sleep deprivation isn’t the only challenge, as temperatures will vary between the extremes of 30°C and -20°C. Special food has been developed to withstand the conditions while providing the pilot with vital nutrients to remain alert during the flight.
The aircraft originally took off on its incredible journey from Abu Dhabi on March 9, flying to Muscat. Since then, the plane has traveled to Ahmedabad, India; Varanasi, India; Mandalay, Burma; Chongqing, China; Nanjing, China and most recently the unschedule stop in Nagoya, Japan.
Originally the solar-powered airplane planned to fly all the way from Nanjing, China, to Kalaeloa, Hawaii, a trip anticipated to take five to seven days. However, the plane was forced to land in Japan after just 44 hours and 10 minutes.
Manned by only one pilot at a time, Solar Impulse 2 has been flown by Bertrand Piccard and André Borschberg on alternating segments of the epic trip. The two Swiss natives are also the founders of Solar Impulse.