As Neil Parker dragged his broken body along an isolated Australian bush track, thinking he would likely die out there, he channelled his mind on reconnecting with his estranged son living in New Zealand.

The seasoned bushwalker, 54, had broken his leg and wrist after he fell six metres from a waterfall while hiking alone at Mount Nebo, north-west of Brisbane, on Sunday.

His mobile phone was drenched and unusable after he plunged into the water, and he had given his personal alert device to his ex-wife.

Speaking from his hospital bed on Wednesday, the day after he was airlifted to safety, Parker said he knew his only chance of survival was to fasten a splint from his walking poles and drag himself to safety.

"I caught myself the first time as I started to slide but I had too much momentum and over I went.

"I started sliding down the face of the rock and I slid about 20 foot, cartwheeled then slammed into the rock then landed into the creek at the bottom.

"Straight away I thought, 'Now I am in a lot of trouble, nobody knows where I am, I don't have a personal location beacon'."

Parker had spent seven years as an SES volunteer and had worked on several rescues himself.

"I knew where I was located, there was going to be no way they could find me," he said.

"Inch by inch" he began to drag himself along the three-kilometre track to a clearing where he thought helicopters would be able to spot him.

"My left foot, the bottom, just above the ankle - clean snap in half - so the whole bottom of my leg came loose," he said.

"Legs are very heavy when they aren't connected to anything and trying to pick it up over rocks ... I would get about a metre, metre-and-a-half each time before I would have to stop and take a break.

"What took me 40 minutes to walk up, took me two days to crawl down."

With just a handful of nuts, a protein bar and some liquorice to eat, Parker spent two nights out in the bush.

"At night-time I was sleeping on rock, I had been crawling on rock all day - everything was hard so most of the pain I was going through was constantly being on hard rock.

He said he did not actually get much sleep thanks to his broken leg continuing to spasm in the cold.

"I think I have a very high [pain] tolerance, I had no issues with pain while I was crawling around, I didn't feel any discomfort or that while I was crawling but that could have just well and truly been adrenalin pumping."

The relief finally kicked in after he was spotted by a rescue helicopter on Tuesday afternoon.

"I had had enough of laying on rocks and I just started imaging nice fluffy pillows," he said.

As to what kept him going, he said it was sheer determination to see his sisters, children and ex-wife.

"The family connection, wanting to get back and let them all know I was OK kept driving me," he said.

"[My sister] rang my kids in New Zealand and my son said he would fly over next week.

"I have been disassociated with him for the last two years, so I only just came back together with him four or five weeks ago," he said, tearing up.

"Gee, I wanted to talk to him.

"So that was the main reason, I wanted to get home to my kids."

He was airlifted to the Princess Alexandra Hospital and credits his survival to his preparedness and the rescue mission mounted by his family with the support of the Brisbane Bushwalkers community, whose members set out on Monday to find him.

Orthopaedic surgeon Nicola Ward said Parker would remain in hospital for at least the next two weeks and was expected to go into surgery on Wednesday afternoon.