Investigators in the Sydney seaplane crash say they will be looking into whether there were any similarities to incidents involving the same model of seaplane, including one which killed another British family in 2015.
Air accident investigators are examining the wreckage of the De Havilland DHC-2 Beaver, which plunged into the Hawkesbury River off Jerusalem Bay, 25 miles north of Sydney city centre, on New Year's Eve, killing all those on board.
Richard Cousins, the 58-year-old chief executive of FTSE 100 company Compass Group, died alongside his sons Will and Edward, aged 25 and 23, his fiancee Emma Bowden, 48, and her 11-year-old daughter Heather.
The experienced pilot, Gareth Morgan, 44, also died.
The incident has drawn comparisons to a crash in Quebec, Canada, in August 2015, involving another CHC-2 Beaver plane, in which a British family of four died.
The small aircraft crashed into the side of a mountain, also killing a French passenger and the pilot.
On Tuesday, Nat Nagy, executive director of the Australian Transport Safety Bureau, told a press conference that all incidents involving the same model of plane would be looked into as part of the investigation.
He said: "We will be looking at any previous incidents and accidents specifically around this type of aircraft.
"It's been in use and service for many decades so we will be thoroughly looking at it.
"I think it's important not to draw any conclusions that this is something that is a systemic issue. We haven't identified anything previously that there's anything systemic.
"Over the course of this week we will be able to piece together the factors surrounding the accident and from there, if we do identify any issue that is a safety critical issue, we will notify the appropriate authorities immediately."
Mr Nagy said the aircraft was manufactured in 1963, and that it was not unusual to have a plane of that age still in use.
The exact circumstances surrounding Sunday's crash remain unclear, and investigators are working to reconstruct the events leading up to it.
Mr Nagy told reporters the Sydney Seaplanes flight had left Cottage Bay Inn, where the family had reportedly enjoyed a meal, at about 3pm, for a return flight to Rose Bay, near Sydney Harbour.
He said the plane made a right hand turn prior to the impact with the water about 10 minutes later.
His team will now be examining the aircraft data to find out what happened at the time of the incident, including whether the plane was operating at full power and whether it was climbing or descending at the time.
Any recovered mobile phones, iPads and GoPros will also be examined by experts.
After the Canadian crash in 2015, a report by the Transportation Safety Board of Canada (TSB) found the plane, operated by Air Saguenay, stalled in a steep turn and descended vertically before crashing into the mountain and bursting into flames.
Fiona Hewitt, 52, her husband Richard, 50, and children 14-year-old Harry and 17-year-old Felicity, all from Milton Keynes, died.
The TSB recommended that the Candian Department of Transport required that all commercial DHC-2 aircraft in Canada be fitted with a stall warning alarm.
Mr Nagy said it was not yet clear whether the plane involved in the Sydney crash had a warning system fitted.