Canberra: The model of seaplane that crashed on New Year’s Eve, killing five Britons and the plane’s pilot, is generally reliable, the Australian Transport Safety Bureau said on Tuesday.

The plane crashed in the Hawkesbury river, north of Sydney, at 3.10pm local time on Sunday and has yet to be retrieved.

The experienced pilot, 44-year-old Gareth Morgan, died along with his passengers: the high-profile 58-year-old UK businessman Richard Cousins; his sons, Edward and William Cousins, aged 23 and 25; his fiancee, 48-year-old Emma Bowden; and her daughter, 11-year-old Heather Bowden-Page.

The 1964 DH C-2 Beaver seaplane is the same model of aircraft that crashed in Canada in 2015, killing another British family. Australian investigators were unable to say whether the plane that crashed on Sunday was fitted with a warning system recommended by Canadian authorities following the investigation into that crash.

But they hope to piece together the final moments of the seaplane flight. Police divers worked until nightfall to recover the six bodies.

The family was on holiday in Sydney and returning from lunch at the Cottage Point Inn when the crash happened.

“The aircraft took off in a north-easterly direction, followed by a turn to the north-west, then a subsequent right turn before impacting the water,” the ATSB executive director of transport safety, Nat Nagy, said.

One witness, Will McGovern, rushed with his friends to the downed plane after it hit the river.

“The water was full of fuel, a massive slick across the top and the fumes actually burned your eyes,” he told the ABC. “The boys were in the water diving down, trying to help these people inside the plane.”

But the plane quickly sank, nose down, and remains on the riverbed.

Nagy and the other investigators, who have data retrieval and aviation expertise, worked with divers at the crash site on Tuesday to assess how best to recover the wreckage.

A crane or airbags are being considered as options to refloat the plane, hopefully on Thursday.

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 once the plane was recovered.

Investigators are hopeful data can still be recovered from 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,” Nagy said. “We’ll also be talking to witnesses to try and piece together those final moments before the aircraft impacted the water.”

Cousins was the chief executive of the world’s largest food catering company, Compass Group, and was a keen cricket fan.

The former England cricket team captain Michael Vaughan, tweeted: “Saddened to hear of the passing away of Richard Cousins and some family members in Sydney ... Great man who loved the game of cricket ... Thoughts to all his family.”

The English team’s supporters, the Barmy Army, plan to hold a minute’s silence at the start of the fifth Ashes test on Wednesday.

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 DH C-2 Beaver plane emerge, authorities will be quickly notified, Nagy said.

“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.”

Sydney Seaplanes has suspended all flights indefinitely following the tragedy.