A fatal plane crash that killed a father and son was caused when the plane struck a stray power line, a new report has found.
Ben Mumford, 50, and his son Charlie, 24, died when their Cessna 172N aircraft crashed near their property in Merriton, 190km north of Adelaide, at 4.15pm on October 8, 2023.
Mr Mumford was taken to the Royal Adelaide Hospital in a critical condition, where he later died. His son was pronounced dead at the scene.
An Australian Transport Safety Bureau (ATSB) report has revealed that Mr Mumford collided with a single-wire power line as he attempted to land, causing the plane to crash into the ground and burst into flames.
The report found that the stray power line was 25 feet above the ground and increased the risk of a crash due to its location at the end of the runway.
A plane piloted by Ben Mumford and his son Charlie crashed after hitting a lone power line during their landing
The runway – on private land owned by Mr Mumford – was surrounded by grass and ATSB chief constable Angus Mitchell found that Mr Mumford had probably lost sight of the power line during landing.
“Power lines, especially single wires, are notoriously difficult to see from the air and pose a constant hazard to aircraft, as this tragic accident demonstrates,” Mitchell said.
‘[The powerline] was not sufficiently marked to increase the visibility of pilots using the runway – and there was no requirement to do so.
‘This underlines the importance that runways on rural properties must be properly separated from power lines, even if the strip is only intended for use by pilots familiar with the wires.’
When Mr. Mumford’s plane cut the power line, it immediately crashed into the ground and exploded in a fuel fire.
The report found that the pilots had to land halfway down the 700-meter runway if they wanted to avoid the line.
An Australian Transport Safety Bureau report shows the pilot is believed to have lost sight of the power line during his descent to Mr Mumford’s Merriton property on October 8, 2023.
A marker had previously been placed on an adjacent pole to warn pilots of the lonely line that was not visible to approaching aircraft, Mr Mitchell noted.
‘This [marker] was to alert pilots flying past it to the presence of another power line crossing above or below, rather than as they approach the runway.
‘Furthermore, when passing over a power line that is seen, the oblique orientation relative to the runway can also increase the chance of a wire strike due to a pilot misjudging the point where the aircraft would come into conflict with the wire.’
In South Australia, property owners can request telecoms and energy companies to place markings near anything that could be dangerous low-level flight operations.
Mr Mitchell urged rural areas property owners to check their own carefully runways to ensure wires are marked correctly.