Twenty-one Kiwis from Northland to Otago will touch down in Australia later tonight to help with the mammoth firefighting effort.

New Zealand has sent more than 200 personnel since last October. This latest team will spend two weeks in Canberra working up to 16-hour days.

For Northland father Rory Renwick, it will be his seventh time returning to Australia.

"Leaving the family is always a challenge," he told 1 NEWS. 

"You definitely miss them and there's a bit of that in return as well."

The Kiwis will be doing a variety of work, including managing aircraft and other tasks.

"It'll be structure protection, protecting communities, back burning and lots of direct attack," Mr Renwick says.

"There’s been some rain and that'll knock the fires until the wind blows off the desert again, so it's a matter of doing as much work as possible before the wind come off the desert and they flare up again."

It's a nervous time for Mr Renwick's wife, Nicky, but she says she'd never hold him back from doing what he loves.

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"Trees falling down on firefighters is the one way you hear of the demise of firefighters, so that’s my biggest worry," she told 1 NEWS.

"We've lost friends in helicopters fighting fires so I just shut my thoughts off while he’s away."

There were some nerves as crews arrived at the airport today, but they all say going was a no brainer.

Taranaki volunteer firefighter Charlotte McGoldrick jumped at the chance.

"As soon as I saw it, I wanted to have my name down," she told 1 NEWS.

"My mum's a bit nervous. I’m her only daughter."

Matt Balks, who will be returning to Australia for the second time after fighting fires in Tasmania, says trees are one of the biggest hazards.

"They’re called widow-makers for one reason," he says.

"They can be silent. I've heard them crashing and it puts the chills through you, it’s just looking to see what's going on above you."

The team will be working closely with Australian fire crews to help protect vulnerable communities.

And while that means their own loved ones at home will have to be just as brave, they know that other families are depending on them too.