Investigators will be looking for possible links between a fatal New Year’s Eve seaplane crash in Sydney and another incident involving the same type of aircraft which killed a British family in Canada in 2015.
They will also look at other incidents involving the same model of plane.
The De Havilland DHC-2 Beaver plunged into the Hawkesbury River off Jerusalem Bay, near Sydney, on New Year’s Eve, killing all 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 aircraft’s Australian pilot, Gareth Morgan, 44, also died.
The incident has similarities to a crash involving another CHC-2 Beaver plane in Canada in August 2015.
A British family of four – Fiona Hewitt, 52, her husband Richard, 50, and children 14-year-old Harry and 17-year-old Felicity, all from Milton Keynes – died in the crash.
The small aircraft had crashed into the side of a mountain in Quebec, killing the family along with a French passenger and the pilot.
The Australian Transport Safety Bureau says all incidents involving the same model of plane would be looked into as part of the investigation.
Nat Nagy, the bureau’s executive director, said: “We will be looking at any previous incidents and accidents specifically around this type of aircraft.
“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.”
The Cousins family had gone for lunch and taken flight about 3pm to return to Rose Bay, near Sydney Harbour.
Mr Cousin was due to step down from his position at Compass in March. The company said its new boss, Dominic Blakemore, has taken charge in the wake of the accident.
Mr Nagy said the plane made a right hand turn before it crashed into the sea 10 minutes later.
Experts will look at whether the plane was operating at full power, and whether it was ascending or descending at the time of the crash.
Following the Canada crash, a report by the Transportation Safety Board of Canada (TSB) found the plane, operated by Air Saguenay, stalled and crashed into a mountain.
The TSB recommended that the Canadian Department of Transport required 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.