NO survivors are expected from the helicopter that crashed in a fireball in remote South Australia with three veterans of ABC News aboard.

But police say the intensity of the fire that engulfed the chopper near Lake Eyre means it could take several days before the bodies are formally identified.

Reporter Paul Lockyer, pilot Gary Ticehurst and cameraman John Bean were in the helicopter that crashed last night while they were filming a third documentary of Lake Eyre filling up with water.

"We are not expecting to find any survivors," Assistant Commissioner Neil Smith, of SA police, said today.

"We know that there was three people on the aircraft ... and we know that there are no people there now."

The wreckage is strewn across a large area, which is surrounded by boggy ground and water, and details are sketchy because satellite phone communication keeps dropping out, Mr Smith said.

Disaster identification experts had been sent to the area but positive identification could take several days.

"With the intense heat of the fire and the devastation of the crash scene this is not an easy task."

Before the crash the helicopter landed and those on board had a conversation with a tour guide and some people in the area, and then departed.

"When it was approximately two to three kilometres from the area, the tour guide ... noticed a large fire ball in the distance," he said.

Mr Smith said the guide and a nurse used a boat to get to the crash site, which was on dry land surrounded waters.

The helicopter crashed on the eastern side of Lake Eyre, approximately 142km northeast of William Creek and 146km north-northeast of Marree.

William Creek pilot Trevor Wright told Adelaidenow.com.au that the helicopter been carrying out aerial photography and video work when it went down.

"When the helicopter didn't turn up, they became anxious and sent out a search party on foot; then they found the wreck," Mr Wright said.

The ABC reported that a person at an outpost station had seen the helicopter going up in flames.

Outback tourism operator Rex Ellis says he was the guide that was first on the scene after the crash.

"They just took off and went pretty low on the other side of the river and then gradually went out of sight behind dunes," Mr Ellis told the ABC.

"We didn't see anything, just saw a glow and we realised that something pretty bad had happened."

He told the ABC he called the Flying Doctor, got in a boat and headed for the crash site.

"We had to sort of cross through about 'half a K' of shallow water ... and then we had to sort of walk into the site."

He said it took about an hour and when he arrived it was clear there was nothing they could do.

Mr Smith said the guide had called emergency services by satellite phone.

A helicopter, carrying emergency and police personnel, was sent from Adelaide and arrived at about 2am (CST) and confirmed the incident.

The Australian Transport Safety Bureau (ATSB) will investigate the crash and is en route to the site.

Mr Smith said that due to the communication problems and difficult terrain it would take several days to get a clearer picture of what happened.

"In the far north and the far west of the state it is always very challenging."

In a career spanning more than 40 years, Lockyer has worked as a correspondent in Washington, Singapore and throughout Asia and won a Logie Award for best TV reporter.

The three men were considered leaders in their fields.

Bean, who is married to an ABC staff member in Brisbane, has worked for the 7.30 Report, Catalyst, the New Inventors and Gardening Australia in his 20-year career with the broadcaster.

Ticehurst has close to 40 years of helicopter operational experience, which includes 30 years as chief pilot of Film Helicopters.

Lockyer was one of the ABC's most experienced and popular reporters.

He started at the ABC's Perth office in 1969 before moving to Sydney and then to Canberra in 1976, where he covered the fallout from the dismissal of the Whitlam government.

His career then took him to Indonesia, Washington, and then back to Australia in 1988, this time with the Nine Network.

More than a decade later he was back at the ABC, covering the Sydney Olympic Games - which earned him a Logie Award as the Most Outstanding TV News Reporter in 2000.

In 2011 he and his crew were the first media to fly into the town of Grantham, by helicopter, the morning after it had been all but destroyed by the massive floods that swept down the Lockyer Valley.

This morning tributes were pouring in for the men who were all held in high regard by family, friends and colleagues.

ABC managing director Mark Scott said: "It's been the longest of nights and we think it will be the saddest of days here at the ABC.

"Paul, Gary and John have each given decades of service to the ABC. They are passionate about their work and finding great stories from all over Australia to bring to the public.

"Our love, thoughts and prayers go out to family and friends of Paul, Gary and John at this terrible time."

Mr Bean's wife, Landline reporter Pip Courtney, said her husband was "the most wonderful husband a girl could wish for".

"Devastated, broken, I will be lost without him," she said in a statement to the ABC.

"I fell in love with him on the road and adored working with him. He was so, so talented, I loved watching him at work. So privileged. I can't believe he's gone. Our families are devastated."

ABC head of news gathering Don Lange said support was pouring in from around the world.

"We have been overwhelmed by support from both within this organisation and the industry, and correspondents from across the world who have worked with Paul and Gary and John have been calling all night and this morning."

The experienced news trio were filming a third documentary of Lake Eyre filling up with water.



Read more about the tributes flowing into the ABC for the three men.