Bad weather delays round-the-world solar plane's journey

Bad weather has caused the organizers of Solar Impulse 2, an airplane powered solely by alternative energy, to postpone on Tuesday the seventh leg of its round-the-world journey, during which it has to cover most of the Pacific Ocean, Efe news agency reported.

Current weather formations over the Pacific are unstable and the potential for excessive clouds over the region, which could affect the recharging of batteries that power the engine, led them to postpone the take-off to a later date yet to be determined, the Impulse team explained in a statement.

The organisers said that the trip, initially expected to last five days and five nights, could take up to a week due to bad weather, and potentially place the pilot in excessively extreme circumstances.

After more than a month in Nanjing in eastern China, the team announced on Monday that the airplane would take off for the Hawaiian islands at 7 p.m. GMT, but aborted the plan at the last moment.

On April 21, Solar Impulse reached Nanjing from Chongqing in central China.

Climatic conditions are a constant challenge on the journey, coupled on this leg with the great distance, 4,971 miles, that the airplane must fly.

The Impulse has flown a total of 3,728.2 miles in six stages since it began its trip from Abu Dhabi on March 9.

Organisers plan for the airplane and its more than 17,000 solar cells to fly around the world in 12 stages.

So far it has made stopovers at Muscat (Oman), Ahmedabad, Varanasi (India), Mandalay (Myanmar), Chongqing and Nanjing (China).

Swiss pilots Bertrand Piccard and Andre Borscheberg have taken turns on different stages of the journey.