At the time of the last tyre change, crack initiation at the bearing bore shoulder radius was an emerging issue with no requirement for mandatory inspection of this area during a tyre change.
The post-2005 main landing gear wheel design had shown a susceptibility to fatigue cracking at the inner hub bearing bore shoulder radius.
There was no formal risk assessment process in use at the operator’s Horn Island base.
There was the potential for the incorrect use of the dipstick to result in the over-reading of the fuel quantity.
Information contained in the approved flight manual and pilot's operating handbook was not applicable to the engine that was fitted to the aircraft.
The Registered Operator's maintenance control practices did not ensure compliance with all Airworthiness Directives.
The location of the decompression panel and absence of cabin floor sealing above the main equipment centre increased the risk of liquid ingress into the aircraft’s electrical systems.
The galley drain operation and maintenance processes did not adequately prevent blockage and overflow of the aircraft’s drain lines.
The removal of fluid quantity markings from, and unapproved modifications to the helicopter’s spray tank by the operator increased the risk of overweight operations
The Aerial Agricultural Association of Australia suggestion that an additional hazard identification check be carried out prior to a cleanup run was not routinely practiced by the pilots, or monitored by the operator.
The operator’s flight crew quick reference handbook did not include sufficient information for flight crew to manage the emergency.
The floor sealing around the forward galley was not of sufficient extent to prevent liquids from passing through to the under floor area.
The United States Federal Aviation Administration regulations and associated guidance material did not fully address the potential harm to flight safety posed by liquid contamination of electrical system units in transport category aircraft.
Maintenance processes did not identify or correct the deterioration of the galley floor sealing
Maintenance processes did not identify or correct the inoperability of the forward drain line heater.
Maintenance processes did not identify or correct the corrosion in the generator control units.
Maintenance processes did not identify or correct the deterioration of the drip shield.
The aircraft operator’s documented design objectives did not explicitly require the protection of non-structural systems from liquid contact or ingress.
The priority level of the battery discharge messages that were provided by the engine indicating and crew alerting system did not accurately reflect the risk presented by the battery discharge status.
There was no direct supervision of the joint testing operations.
