Coroner Sue Johnson yesterday released her findings into the "absolutely tragic" deaths of Nadine (33) and Angus (3) Tomlinson, who drowned on September 30, 2018, when the tractor Mrs Tomlinson was driving skidded into a dam on the family’s East Otago farm.
Ms Johnson said a WorkSafe report found various health and safety lessons for the farming industry, which she endorsed.
Since 2000, WorkSafe has recorded workplace fatalities in the agriculture sector involving 42 children and young people (0-18 years old).
The report said passengers must not be carried in any vehicle that did not have sufficient seating, restraints or was not fit for the purpose of carrying passengers.
The farming industry should also take lessons from the investigation that braking distance and efficiency were greatly increased when both right and left brakes were applied correctly on a tractor, the report said.
Mrs Tomlinson, who was 16 weeks’ pregnant with her third child, was driving the 2004 John Deere tractor, accompanied by Angus, on the family’s Dunback farm, with a trailer attached to dispose of a dead animal.
When the pair failed to return two hours later, Mrs Tomlinson’s husband Scott went to investigate and found the animal untouched, skid marks leading to the dam and fertiliser bags floating on the water.
He notified emergency services and the police national dive squad recovered the two bodies the following day.
Mrs Tomlinson and Angus were found outside the tractor.
The left door had been smashed or removed, which police believed occurred when Mrs Tomlinson attempted to escape; she was found with her shirt caught on a trailer cleat.
Senior Constable Alastair Crosland said there were tyre tracks down a steep slope leading directly to the dam.
"The left tyre mark showed clear signs of skidding, indicating that the tractor was being braked as it descended the slope. The onset of skidding suggested that the trailer may not have been braked," he said.
Police notified WorkSafe there was a 30m skid impression on the left-hand side of the track, indicating the left wheel locked up.
NZ Transport Agency vehicle specialist Jeffrey Fleury, who examined the tractor as part of WorkSafe’s investigation, found no obvious faults with the tractor, and that the brake system was working. The trailer also had no obvious faults.
However, the pin connecting the two brake pedals on the tractor was in the "out position" — "... meaning that to activate both rear brakes both pedals needed to be applied", Mr Fleury said.
Tests undertaken showed the tractor would not stop easily and would lock up and sledge, when the single brake was applied.
Mrs Tomlinson was a vastly experienced tractor driver and her competence was not a factor in the accident, Ms Johnson said.
She believed it was "most probable" Mrs Tomlinson became concerned at the speed the tractor was travelling down the steep slope.
"Despite her extensive tractor driving experience it appears that she only applied the left-hand side brake pedal with the intention of turning right in the direction of the dead animal. However this caused the tractor to sledge and continue tracking straight into the dam. The weight of the trailer may also have influenced the braking capability of the tractor."
Ms Johnson said the pair’s deaths were "absolutely tragic" and she extended her sincere condolences to Mr Tomlinson and the wider family.
Mr Tomlinson had since installed a fence around the dam, and thought about the risks that he and his surviving son Sam were exposed to.
Mr Tomlinson could not be contacted yesterday.
