Tonga's new Chinese-gifted plane is still awaiting clearance to be put into operation on domestic routes of the carrier, Real Tonga.
The route between Nuku'alofa and Vava'u is being served by an aircraft of the New Zealand carrier, Chathams Pacific, which had ceased flights in March after learning of the arrival of the Chinese MA-60 aircraft.
At the time it said the Tongan government wasn't willing to offer competition on a level playing field.
The chief executive of Real Tonga, Tevita Palu, says while the MA-60 has been doing practice circuits, it has not yet taken passengers.
Mr Palu says the airline is still waiting for an Air Operation Certificate from an international body, which would allow it to take passengers.
But the Deputy Prime Minister of Tonga, Samiu Vaipulu, has said plane has received international certification to fly.
Last month, the New Zealand government suspended eight million US dollars in tourism aid to Tonga amid safety concerns with the MA-60.