BEIJING » A groundbreaking solar-powered plane successfully flew from Myanmar to central China early Tuesday as part of an historic round-the-world journey promoting renewable energy use.

The organizers of the Solar Impulse 2 flight wrote in a statement that the plane landed in Chongqing, China, at 1:35 a.m. Tuesday, after leaving Mandalay, Myanmar, more than 20 hours earlier.

Two Swiss pilots, Bertrand Piccard and Andre Borschberg, are flying the state-of-the-art plane, which is powered by more than 17,000 solar cells on its wings. They are attempting the first ever round-the-world flight by a completely solar-powered plane.

The statement said the pilots had to make a steep climb to cross mountainous terrain in southern China. The pilots wore oxygen masks in the unpressurized cockpit, where temperatures dropped to minus 4 Fahrenheit.

The Solar Impulse 2 started its journey from Abu Dhabi on March 9 and made four stops before arriving in China. It flies next to the eastern Chinese city of Nanjing before heading to Hawaii on its five-month trip.