Tongan tourism operators say safety fears over the country's MA60 aircraft are crippling business.

Earlier this year, the New Zealand Government suspended millions of dollars in tourism aid to Tonga and warned travellers of safety concerns over the plane, which is flying for Real Tonga airline.

New Zealand says the MA60 plane has been involved in a significant number of accidents in the past few years and is not certified to fly in New Zealand, Australia, Europe and the United States.

Australian Lisa Kingsberry was travelling from Fiji to Vava'u in Tonga and has told airline troubles delayed her in the capital, Nuku'alofa, for two days.

"They informed us that the pilot had been rushed to hospital and they were trying to replace the captain," she said.

"The weather was perfect...and throughout the day this is the story that they kept telling us.

"Then we were told they were grounded for another day...told that the captain was still sick...and then weather had caused the flights to be grounded."

She says when the plane did depart, she'd never been on such an anxious flight.

"As we got on, the exit sign on the plane fell off, and they couldn't put it back on so they just took the exit sign off from the plane," she said.

"As we ascended off the runway, water started running from the cabin...we were sitting in the emergency aisle and it landed straight on top of me unfortunately.

"I've never been on such an anxious flight...everyone was talking about the safety issues.

"I've never seen so many people pay attention to the safety demonstration - it was like meerkats popping up - noone missed the safety demonstration. So it was an incredibly tense flight."

In July, Tonga was gifted a Chinese-made Xian MA60 for its domestic Real Tonga airline by China.

Since 2009, MA60 aircraft have been involved in 11 incidents, including three of them in the last two months.

Earlier this year, Myanmar grounded its MA60 planes for safety checks after two crash landings.

Most of the crashes were caused by technical or system failures.

Ms Kingsberry says local operators are fed up with the safety issues and delays caused by the airline.

"I spoke to quite a lot of tourism providers and they say it's absolutely crippling them," she said.

"The people on our flight...were either Australians or New Zealanders and I can tell you now that the tension and concern that existed around the flight...that will now go back to all of their families and all of their friends.

"If something bad happens you tell 20 people, if something good happens, you tell five, so their concern is more for the next season, rather than the end of this season."