Hawaii residents bid farewell to the Solar Impulse 2 today, as the aircraft powered only by the sun’s rays ended a nine-month layover in the islands and resumed its round-the-world journey.

Crowds cheered as Solar Impulse 2 took to the sky at 6:15 a.m. with Swiss Pilot Bertrand Piccard at the controls. The departure came after a brief scare when winds forced crew to roll the aircraft back into the hangar for an hour delay.

Piccard is attempting to fly to Moffett Airfield in Mountain View, Calif., south of San Francisco. The flight from Hawaii to California will take approximately three days as Piccard is expected to land Saturday.

Before boarding, Piccard said it was tough to leave Hawaii because of the friends he and the team have met since the aircraft landed in July.

“Moving from here is emotional but we’re happy to continue the flight,” Piccard said. “Thank you for your support. We are leaving a lot of friends.”

Solar Impulse 2 has been sitting at Kalaeloa Airport since Piccard’s partner, Swiss pilot Andre Borschberg, touched down from Japan in July after five days of non-stop flying. The journey from Japan to Hawaii set a record for the longest solar flight both by time and distance.

“I share Bertrand’s feeling (about Hawaii),” Borschberg said. “It’s hard to leave this island.”

After nine months of waiting for battery repairs, longer daylight hours and good weather Solar Impulse 2 was cleared for takeoff.

“I’m extremely happy that Bertrand is in the air,” Borschberg said. “We have one window and if you miss it, it is postponed for a few days.”

Families, friends and aspiring aviators gathered to see the plane off, some arriving as early as 1:30 a.m. on Thursday.

Native Hawaiian master navigator Nainoa Thompson hugged the pilots goodbye and presented them with fishhooks made by Kamehameha Schools students. Thompson said the hooks were symbolic for the great fishhook of the Hawaiian mythology culture hero and ancient Chief Maui.

Thompson is the captain of the Hokulea, the Polynesian voyaging canoe sailing around the globe promoting sustainability.

The Hokulea crew also gave the fishhooks to Desmond Mpilo Tutu, a South African social rights activist and retired Anglican bishop; the Dalai Lama; and Sir Richard Branson.

“When (Hokulea) runs around the world, we give the fishhooks to those who are making a difference to the earth,” Thompson said. “When you get a chance to sit down with the pilots, it is very similar to what we go through.”

Hawaii was the first of five U.S. destinations for the plane. After California, Solar Impulse 2 will stop in Phoenix, head to an as-yet-undetermined stop in the Midwest, land in New York before the Atlantic crossing. After New York the plane will land in either North Africa or South Europe and then head back to Abu Dhabi where the journey began.

Since leaving Abu Dhabi, United Arab Emirates, in March 2015, the plane has traveled to Muscat, Oman; Ahmedabad and Varanasi, India; Mandalay, Myanmar; Chongqing and Nanjing, China; and Nagoya, Japan.

Piccard and Borschberg alternate who pilots the plane at each stop. Together, Piccard and Borschberg will rack up about 500 flight hours during the around-the-world voyage in the plane’s 4-by-6 1⁄2-foot cockpit.

The plane’s wings were built using more than 17,000 solar cells, four electric motors and lithium batteries to replace the need for fuel. Its 236-foot wingspan matches that of a Boeing 747 jumbo jet and it weighs the same as a family car with the power of a small motorcycle. Solar Impulse 2 has a team of 80 engineers and technicians.