Air crash investigators are gathering data and talking to witnesses as they attempt to piece together the moments before a seaplane smashed into the Hawkesbury River, killing six people.
Three investigators from the Australian Transport Safety Bureau with data retrieval and aviation expertise are at the site of the New Year's Eve crash to assess the wreckage for retrieval.
Police divers are helping the investigators decide how best to refloat the plane which hit the water shortly after take-off, ATSB executive director of transport safety Nat Nagy told reporters at Apple Tree Bay on Tuesday.
Investigators hope that will be done on Thursday, he said.
Mr Nagy said it was too early to speculate on the cause of the crash but all aspects of the aircraft, from mechanics to its history, would be examined closely.
Investigators are hopeful data can still be recovered from both the plane's avionic instruments and smartphones or cameras on board.
"As well as that we will be looking at the maintenance records, of the aircraft, talking to the operator, look at the pilot's background and experience," he said.
"We'll also be talking to witnesses to try and piece together those final moments before the aircraft impacted the water."
Mr Nagy said the evidence, once retrieved from the riverbed, would be taken to Canberra for full examination.
It will take about 30 days for a preliminary report into the cause of the crash to be published but, if any urgent issues around the DHC-2 Beaver plane emerge, authorities will be quickly notified, Mr Nagy added.
"This is a tragic and sad end to 2017," he said.
"It's the ATSB's role to investigate transport and safety accidents and incidents such as this and to work out what happened with the key goal of trying to prevent accidents like this from happening into the future."
On board the plane when it plunged into Jerusalem Bay were experienced pilot Gareth Morgan, 44, high-profile UK businessman Richard Cousins, 58, his sons, Edward and William Cousins, aged 23 and 25, his fiancee Emma Bowden, 48, and her daughter, Heather Bowden-Page, 11.
Richard Cousins was killed alongside his two adult sons when a seaplane crashed into a river north of Sydney. Source: AAP
Mr Cousins was the CEO of the world's largest food catering company - Compass Group.
The family was on holiday in Sydney and returning from lunch at the picturesque Cottage Point Inn when the crash happened.
Sydney Seaplanes has suspended all flights indefinitely following the tragedy.
Operators of the seaplane which plunged into the Hawkesbury river have paid tribute to the pilot. Source: AAP
