A FAMILY of five died in a plane crash in Australia in a “tragic” event in which their pilot was “likely” poisoned by carbon monoxide, a court has heard.

Businessman Richard Cousins, who grew up in Bracknell, his two sons Edward and William Cousins, from Hides Heath in Buckinghamshire, and his partner and her 11-year-old daughter, Emma Bowden and Heather Bowden-Page, all died when their sea plane crashed into the water in New South Wales on New Year’s Eve 2017.

At an inquest today, coroner Alison McCormick said the plane crashed when it entered Jerusalem Bay, a confined area.

"Experienced" Canadian pilot Gareth Morgan, who had taken the family out on a sightseeing trip, operated a steep 270 degree turn over the bay which “probably” caused the plane’s propellers to stall.

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There was “insufficient” time for the de Havilland Canada DHC-2 Beaver plane to recover before it hit the water, killing all six people on board and destroying the aircraft.

Tests carried out after the incident found the family and the pilot had elevated levels of carbon monoxide in their blood.

Richard Cousins and his family passed away following a plane crash in 2017.

Richard Cousins and his family passed away following a plane crash in 2017.

Ms McCormick said the pilot’s ability was likely “significantly reduced” because of high levels of carbon monoxide in the plane, which likely caused him “confusion” and “visible disturbance" and "disorientation.”

The coroner said a 27-minute taxi with the plane door open and cracks in the plane's exhaust likely contributed to the high levels of carbon monoxide in the cabin.

A carbon monoxide detector was installed in the plane, but it was likely not working having been sun-bleached.

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Reading evidence from the Australian Transport Safety Bureau, the coroner said the authority had issued safety notices urging operators and owners of float planes to install devices which detect carbon monoxide levels and carry out regular checks following the crash.

Ms McCormick stated that Richard Cousins, the 58-year-old CEO of foodservice company Compass who studied at Brakenhale School growing up, died from multiple blunt force injuries in what was officially ruled as an accident.

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His sons Edward, who was 23, and William, who was 25, died of drowning and head and facial injuries respectively.

Emma Bowden, who was 48 and who lived in Tooting with Richard, died of a head injury and drowning.

Richard Cousins and his family passed away following a plane crash in 2017.

Richard Cousins and his family passed away following a plane crash in 2017.

Her eleven-year-old daughter Heather also died of head injuries and drowning.

Richard Cousins had a house in Hyde Heath, near Amersham, and played cricket at Hyde Heath Cricket Club.

He moved to the Chilterns in around 2000 with his first wife Caroline, a teacher, who passed away after a battle with cancer.

Friends and colleagues described Mr Cousins as "well known and respected" after he helped transform Compass' fortunes upon becoming the ailing catering firm's boss in 2006.

 Undated handout photo issued by Compass Group of their Chief Executive Richard Cousins who alongside his fiancee, his two sons and her 11-year-old daughter died in a seaplane crash on New Years Eve alongside his fiancee. PRESS

Undated handout photo issued by Compass Group of their Chief Executive Richard Cousins who alongside his fiancee, his two sons and her 11-year-old daughter died in a seaplane crash on New Year's Eve alongside his fiancee. PRESS

Addressing two family members who attended the inquest, Ms McCormick said: “It must have been a terrible tragedy for your family to lose five people in such tragic circumstances at a time when they should have been having so much fun.

“I know it has taken some time to get the findings back.

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“But I hope the findings may well stop anything similar happening in the future to stop other families going through what you have done.”

The inquest took place at Reading Coroner’s Court on Tuesday, May 24.