The solar-powered plane known as Solar Impulse 2 has cleared the most dangerous leg of its voyage around the world, landing safely on the Hawaiian island of Oahu on Friday morning. The plane had taken off from Nagoya, Japan, last Sunday.
The grueling 116-hour voyage over nearly five days allowed the solo pilot only about three hours of rest per day, broken up into 20-minute sessions while the craft was flown by autopilot.
This latest accomplishment proves that “energy efficiency, solar power, and modern technology can achieve the impossible,” Solar Impulse co-founder and alternating pilot Bertrand Piccard tweeted.
On this leg the Solar Impulse crossed more than 4,000 miles (6,400 kilometers) of ocean, the same desolate region where Amelia Earhart disappeared 77 years ago. But it wasn’t all smooth going. In addition to exhaustion Borschberg battled turbulence and cold fronts, which buffeted the lightweight, experimental plane. (The Pacific’s tumultuous weather this time of year had kept the mission grounded for weeks before finally improving enough for safe passage.)
Borschberg also had to overcome a malfunction in the on-board warning system. That meant “an important support for me is not available, specially in situations such as resting or even sleeping,” the pilot said in an email.
To compensate, two members of the mission control team in Monaco began constant monitoring of the craft, with the ability to manually trigger an alarm for Borschberg if needed.
The team has already begun searching for another weather window, one that will allow Picard to fly Solar Impulse on the ninth leg of its journey, a 3,000-mile (4,800-kilometer) flight from Honolulu to Phoenix.