The pilot of the Gippsland Aeronautics GA-200C aircraft had been
tasked to apply superphosphate fertiliser to a sloping paddock
located close to steeply rising terrain. He reported that prior to
commencing spreading operations he intended to conduct an aerial
inspection of the area. The pilot had flown in the area before and
was familiar with the general terrain.
The pilot reported that just before reaching the treatment area,
his aircraft encountered sinking air. Although it appeared that
adequate terrain clearance existed to fly the aircraft straight
ahead and under powerlines spanning a valley between two hilltop
poles, the pilot became concerned about the possibility of an
unseen power line between a nearby group of buildings and the
nearest hilltop pole. Accordingly, he applied full power and turned
the aircraft toward higher terrain. To improve the climb
performance of the aircraft, the pilot dumped the contents of the
hopper, however he was unable to manoeuvre the aircraft to avoid
colliding with the terrain.
A witness reported that he saw the aircraft fly out of a gully
towards steeply rising terrain, and recalled that the engine had
sounded normal up to the point of impact. The aircraft struck the
ground in a wings level attitude, approximately 6 m below the
hill-crest and stopped in a distance of less than 10 m.
While running to the aircraft, the witness noticed that a fire
had broken out in the wreckage and was slowly spreading through the
centre fuselage area. The witness assisted the pilot to move clear
of the wreckage.
The pilot sustained burns to his face, both arms, and one hand.
He also suffered a fractured skull, a depressed fracture to a
cheekbone, spinal injuries and a broken ankle. At the time of the
accident he was wearing a helmet, a shirt with cut-off sleeves and
denim jeans. Impact forces and post-impact fire destroyed the
aircraft.
It was reported that the fuel tanks located in each wing
remained intact and contained a significant quantity of fuel, which
was not burnt in the post-impact fire. The aircraft's battery was
equipped with a 50 amp circuit breaker that had tripped during the
accident, thereby removing power from the electrical system. A
possible ignition source for the fire was a low-voltage electric
livestock fence that was in contact with the wreckage. The fire was
fed by fuel leaking from the fuselage mounted fuel collector
tank.
The tethering cable for the pilot's upper body restraint was
reported to have failed in a mode consistent with a load that had
exceeded the design requirements of the harness restraint system.
The front and rear supports for the pilot's seat had folded
together and distorted the seat pan. The design of the seat and
harness system had been tested and demonstrated to be compliant
with the 25 G static test requirement.
The pilot subsequently reported that there was not a powerline
between the buildings and the nearest hilltop pole as he had
anticipated.
The Australian Transport Safety Bureau did not conduct an
on-site investigation.