After nearly a week’s wait for optimal winds, Hokule’a left Hawaii shores Friday afternoon for the open sea — and what aims to be a historic, three-year odyssey of aloha around the world.

The voyaging canoe cast off just after 1:45 p.m. as hundreds of well-wishers lined the shores at Palekai in Hilo to bid aloha to the crews. Her escort vessel, Hikianalia, followed Hokule’a out into Hilo Bay several minutes later.

The more than 50,000-mile journey will eventually take the renowned double-hulled voyaging canoe, first launched in 1975, and Hikianalia out of the Pacific Ocean for the first time and into unfamiliar waters.

Once the canoes enter the Indian Ocean, likely in August 2015 based on the current sail plan, crews are bracing for new risks from churning, unpredictable seas there, as well as threats of piracy and ship collisions.

Nonetheless, organizers of Hokule’a’s "Malama Honua" ("Care for Our Earth") voyage say the journey’s purpose is worth the risk. The canoes and their crews aim to export a message of aloha and cultural harmony to the about 85 ports and 26 countries they plan to visit in the coming years.

They further look to rally people across "island Earth" around the 21st-century problems of vanishing natural resources, rising seas and changing climates. Crew members also hope the voyage will inspire Hawaiians to use the islands to pursue solutions.

Hokule’a and Hikianalia now sail for Tahiti on Malama Honua’s first international leg, a trip expected to take 15 to 30 days. To make landfall, the canoes’ 29 crew members will rely on traditional means of navigation their Polynesian ancestors once employed, using the stars, waves and other natural cues to guide them, with Polynesian Voyaging Society President Nainoa Thompson serving as captain and navigator aboard Hokule’a.

If all goes to plan, the two wa’a won’t return to Hawaii shores until 2017.