The wreckage of a helicopter that crashed while fighting fires in Christchurch's Port Hills has been recovered by investigators.

Former SAS soldier Steve Askin, 38, died when the Squirrel helicopter he was flying crashed near Sugar Loaf car park on Tuesday as a dozen choppers were fighting blazes in the area.

On Thursday, the Transport Accident Investigation Commission said it had managed to pull the remains of the helicopter out from the area with fires still raging nearby.

"The wreckage was in a steep gully under the Sugarloaf and conditions were hot and windy, making it challenging for the ground crew loading the wreckage, and the investigators," it said.

The helicopter will now be taken to Commision's facility in Wellington for analysis.

Three investigators had been working at the crash site since Tuesday evening.

Meanwhile, Kiwis moved by the death of the decorated soldier and pilot have been donating generously to his family.

By Thursday morning, nearly 1300 donors had gifted almost $83,000 to a Givealittlepage set up to help Mr Askin's family.

Mr Askin was a former SAS soldier cited multiple times for his exceptional bravery in Afghanistan, the Defence Force says.

He received the New Zealand Gallantry Star, New Zealand's second-highest gallantry award, in 2014, his identity not being made public at the time.

The medal citation said that, during a Taliban attack on the Intercontinental Hotel in Kabul in 2011, Mr Askin was wounded by grenade and rifle fire, but carried on rescuing hotel guests as a fire broke out.

He had a wife, Elizabeth, and two young children.

Mr Askin's father Paul Askin on Thursday told 1 News the family was pulling together to support each other over the loss of his popular son.
"You know I've lost a son but I had him for thirty eight years," he said.

"His little kids are only four and seven, they've lost a dad, it's a huge hole."

Liam Renshaw was in the army with Mr Askin and said the pair had got up to lots of mischief together.

"He touched everybody's lives, he was very charismatic," he said.

"He was a very skilled pilot and had a lot of respect in the industry. He will be missed in the aviation community."