Tauranga sailing icon Jack Thatcher is the key contact point for the waka and will touch base with the crew daily for navigational purposes.
The 56-year-old, who lives by the water in Matapihi, has spent 30 years at sea.
He navigates by the sun, moon, stars and horizon and was one of only a handful of master navigators in the Pacific.
He taught his talent of waka voyaging and celestial navigation to eager sailors and this skill will be on full display in the Tahiti voyage.
He learned to navigate in Hawaii and Micronesia at age 32.
Thatcher said this voyage used the same principles of the navigational practices that Tupaia and ancestors who first voyaged to Aotearoa would have used.
"The two Tahitian navigators will be using the natural environment to guide them - the sun at rising and setting times will greatly help these two navigators to keep their waka on their chosen path," said Thatcher.
"The moon and the stars will also be used to show the way. The stars have many patterns that the traditional navigator must memorise to enable the waka to stay on track."
Manatū taonga Ministry for Culture and Heritage chief executive Bernadette Cavanagh said the passage would be "difficult and dangerous" and would be a testament to the skill of "Māori ancestors who voyaged across the Pacific".
The moment of departure of the double-hulled canoe will be a very special moment, said Tuia 250 national co-ordinating committee co-chairman Hoturoa Barclay-Kerr.
"The voyage will align with the exact time the honouring of the late Sir Hekenukumai Busby will take place at Tūrangawaewae Marae in Waikato," said Barclay-Kerr.
"Sir Hek and other voyagers have been pivotal in the revitalisation of the art form of canoe-building and pacific voyaging," he said.
"It is particularly appropriate that he will be honoured at the moment of departure of the Fa'afaite and crew from Tahiti as the Tuia 250 voyage begins."
After arriving Tauranga, Fa'afaite will be joined by two waka hourua and make the trip to Gisborne to be formally welcomed October 5.
The ceremony will be broadcast live to the nation on that day so we can all hear these stories and share the experience.
The canoe will depart today.