The pilot of solar-powered plane Solar Impulse 2 said on Wednesday (3 June) it would take a week to depart Japan due to minor damage to the plane after bad weather cut short the seventh leg of its round-the-world journey.

The Solar Impulse 2 left Nanjing, China on Sunday to fly over the Pacific Ocean to Hawaii, but bad weather forced the plane to land at a small airport in Nagoya, Japan on Monday.

"Not well... if you're talking about how I slept last night, not well. But I was tired because I had three nights before with little sleep, so yes, partly, but we were all concerned about protecting the airplane," said the pilot, 62-year-old Swiss Andre Borschberg.

He said taking off from Japan will be at least a week later.

"We also had a small damage on the airplane. It was yesterday [we found it] before this difficult night, and it will take about one week for us to repair this small damage, nothing major, but it will take a week in fact to bring some of the materials from Switzerland and to make the repair.

"Then we should be ready in fact to continue and hopefully to reach Hawaii for the next step," Borschberg said.

A giant inflatable air-hanger was erected the night before to protect the plane, powered by more than 17,000 solar cells built into wings, from the rain.

Solar Impulse 2 took off from Abu Dhabi in March. Its journey was originally intended to span approximately 25 flight days broken up into 12 legs at speeds between 30-60mph.