The seaplane involved in the fatal crash that claimed the life of Compass chief executive Richard Cousins made an "inexplicable" sharp turn before it plunged into a river, the aircraft's operator has said.
Cousins died on New Year's Eve when a seaplane he was travelling in with his two sons, his fiancé and her daughter went down in the Hawkesbury River, near the suburb of Cowan in Australia, killing all occupants. The family had been returning from a restaurant in Jerusalem Bay.
The crash killed all six occupants of the seaplane, including the pilot.
A preliminary report drew no conclusions over the cause of the crash and warned that the final report may not be able to offer an explanation.
The report published by The Australian Transport Safety Bureau said that the DHC-2 Beaver had made a steep right turn before nose-diving into the river at Jerusalem Bay.
Sydney Seaplanes described the move as "totally inexplicable".
Chief executive Aaron Shaw said: "The key question arising from the report is why the plane crashed approximately halfway down Jerusalem Bay… The plane simply should not have been where it was."
The pilot, Gareth Morgan, 44, had flown the route "hundreds" of times before and had more than 10,000 hours flying experience.
The report said no evidence had been found of a collision with an object or bird, or pre-impact structural damage.
The ATSB is investigating why he made the move with transport safety director Nat Nagy adding: "We don't have a preferred theory at this stage as to why he went off course."
Cousins was appointed group chief executive of Compass in 2006, following six years as CEO of building materials company BPB.
He was due to step down as chief executive in March and retire from the group in September, but following his untimely death Dominic Blakemore took over the role earlier than planned.
Speaking after the tragedy Compass Group chairman Paul Walsh said: "We are deeply shocked and saddened by this terrible news. The thoughts of everyone at Compass are with Richard's family and friends, and we extend our deepest sympathies to them.
"It has been a great privilege to know Richard personally and to work with him for the last few years. Richard was known and respected for his great humanity and a no-nonsense style that transformed Compass into one of Britain's leading companies."
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