Three Dead After Firefighting Plane Crashes In NSW

Flags will be flown at half mast on Friday in memory of three people killed in a firefighting aircraft crash in the NSW Snowy Mountains region.

Helicopters mounted a desperate search after the NSW Rural Fire Service lost contact with the C-130 Hercules water bomber shortly before 1:30pm on Thursday.

NSW Premier Gladys Berejiklian later confirmed the plane had crashed, with all three American crew members on-board perishing.

The Australian Transport Safety Bureau (ATSB) confirmed it crashed at Peak View, north-east of Cooma.

"Our thoughts and prayers and heartfelt condolences go to their families," Berejiklian said.

"Today demonstrates the fire season is far from over. Today is a reminder of how every single person who is defending life and property is at risk."

Speaking to reporters on Thursday afternoon, NSW RFS Commissioner Shane Fitzsimmons said the aircraft was operating routinely in the Snowy Monaro area at the time.

He said the aircraft impacted heavily on the ground, with initial reports suggesting there was a "large fireball" associated with the crash.

"First and foremost, our thoughts and prayers are with the three occupants who routinely crew that specialised aircraft," Fitzsimmons said.

He said there is no indication what caused the tragic accident, but that the RFS is working with the ATSB to determine what happened.

The ATSB said it is deploying a team of transport safety investigators and will release a preliminary report in about 30 days.

An RFS large air tanker C-130 Hercules. Image: AAP

The Lockheed C-130 was owned and operated by Canadian aerial firefighting company Coulson Aviation and contracted to the RFS.

10 News First understands the plane in question, one of several C-130s operated by the RFS, is named Zeus.

Coulson Aviation confirmed the plane's registration number is N134CG. which is the tail number associated with Zeus.

But Fitzsimmons said he was unable to confirm which plane it was, saying "if I did, I probably wouldn't at this stage disclose any further details about the occupants".

The company has grounded its fleet of Large Air Tankers as a precaution, and a "mark of respect".

In a statement, it said the aircraft had departed Sydney's Richmond air base with a load of retardant and was on a firebombing mission at the time of the accident. 

Image: 10 News First

"The accident is reported to be extensive and we are deeply saddened to confirm there were three fatalities," it said.

"Our thoughts and prayers are with the families of these three crew members onboard."

Coulson Aviation will be sending a team to the site to assist in emergency operations.

Speaking on The Project on Thursday night, Fitzsimmons said it had taken several hours to locate the remains of the wreckage.

"Sure we've lost a valuable aerial asset, but most importantly we've lost three remarkable contributors to the firefighting effort, part of the Coulson Aviation firefighting family that we've worked with now for many years here in Australia."

Prime Minister Scott Morrison said he was "deeply saddened" to learn of the deaths, in what was a "terrible tragedy".

"My deepest condolences to the loved ones, friends and colleagues of those who have lost their lives," he tweeted.

Berejiklian said flags will fly at half-mast in NSW on Friday, out of respect for those who lost their lives.

It comes as fire crews continue to battle hot conditions in southern parts of NSW and the ACT.

At midnight, no fires were burning at emergency level in NSW, however, three remained on watch and act alert, including the Creewah Road blaze in the Snowy Monaro region and the Clyde Mountain fire at Eurobodalla.

The Badja Forest Road, Countegany blaze in the Snowy Monaro, Eurobodalla and Bega Valley regions was also downgraded to a watch and act level just after 11pm.

The  NSW RFS said a slow-moving southerly change reached the far south coast early on Thursday evening and was likely to hit Moruya about 8pm and Sydney about 11pm.

"Difficult conditions continuing for the next few hours," it said.

The NSW death toll from this season's unprecedented fires has now climbed to 24 while more than 2,000 homes have been razed.



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With AAP.