Solar Impulse Si2 Set to Resume Journey in Hawaii

Flight testing begins in preparation for the continued round-the-world flight.

Solar Impulse Si2
The Solar Impulse Si2 has taken two test flights in Hawaii in preparation to continue its round-the-world journey.Solar Impulse

The Solar Impulse team is hard at work in Hawaii preparing the all-solar-powered Si2 for its continued journey around the world. The ambitious trip, which started last spring in Abu Dhabi, was cut short in July following a record-breaking five-day, nonstop flight across the Pacific Ocean from Japan to Hawaii, which put so much stress on the airplane's batteries that the Si2 had to be grounded.

With a new set of batteries now installed, the Si2 has taken two test flights over Hawaii in preparation for the continuation of the round-the-world flight in April. Rather than setting a fixed route, which delayed last year's journey several times due to weather, the team is giving itself several options for the next destination on the United States mainland.

During this most recent test flight, the Si2 soared to 28,000 feet while the Solar Impulse Mission Control Center in Monaco monitored the flight. A new ventilation system for the batteries has been installed, and Solar Impulse test pilot Markus Scherdel stressed the batteries to the maximum during the flight to ensure that the new system would keep the batteries cool. “Overall the flight performed really well,” a Solar Impulse statement said. Solar Impulse co-founder and pilot Bertrand Piccard is scheduled to fly Si2 this week.