Findings From the evidence available, the following findings are made with respect to the collision with terrain involving an Air Tractor AT-502 aircraft, registered VH-LIK, which occurred at an agricultural airstrip 50 km east of Walgett Airport, New South Wales, on 5 November 2016. These findings should not be read as apportioning blame or liability to any particular organisation or individual. Contributing factors The were either never extended, or were retracted at some point during the take-off sequence. This probably resulted in insufficient take-off performance when combined with the high aircraft weight and environmental conditions. The ATSB could not determine at what point during the take-off the flaps were retracted. The pilot attempted to jettison the hopper contents but no significant dump of the chemical occurred and therefore the associated performance gains were not realised. It could not be determined why the load did not dump. The aircraft reached a height the ground where the reduced benefit of ground effect further reduced the aircraft's performance, at a height and airspeed which precluded the pilot from turning the aircraft towards a clear area. This probably resulted in the aircraft descending into trees. Other factors that increased risk was no evidence of appropriate approvals for the modification to the hopper gate box push rod. was no performance data available for the AT-502 aircraft to calculate the required departure runway length. The aircraft was operated under a Civil Aviation Safety Authorityapproved system of maintenance that did not explicitly require a daily or periodic inspection of the hopper dump system.
Findings From the evidence available, the following findings are made with respect to the collision with terrain involving an Air Tractor AT-502 aircraft, registered VH-LIK, which occurred at an agricultural airstrip 50 km east of Walgett Airport, New South Wales, on 5 November 2016. These findings should not be read as apportioning blame or liability to any particular organisation or individual. Contributing factors The were either never extended, or were retracted at some point during the take-off sequence. This probably resulted in insufficient take-off performance when combined with the high aircraft weight and environmental conditions. The ATSB could not determine at what point during the take-off the flaps were retracted. The pilot attempted to jettison the hopper contents but no significant dump of the chemical occurred and therefore the associated performance gains were not realised. It could not be determined why the load did not dump. The aircraft reached a height the ground where the reduced benefit of ground effect further reduced the aircraft's performance, at a height and airspeed which precluded the pilot from turning the aircraft towards a clear area. This probably resulted in the aircraft descending into trees. Other factors that increased risk was no evidence of appropriate approvals for the modification to the hopper gate box push rod. was no performance data available for the AT-502 aircraft to calculate the required departure runway length. The aircraft was operated under a Civil Aviation Safety Authorityapproved system of maintenance that did not explicitly require a daily or periodic inspection of the hopper dump system.
ao-2016-146-final.docx