The design and relative positioning of the external air vent and avionics modules permitted the ingress of moisture and particulates that led to corrosion and contamination of electronic avionics components and consequently the generation of multiple erroneous crew alerting system (CAS) messages due to electrical shorting.
The lack of formalised procedures in place requiring the Air Crew Officer (ACO) to monitor key instrument indications probably contributed to the undetected altitude loss.
The absence of an altitude deviation alert within the Australian Defence Air Traffic System increases the risk of undetected altitude variation and contributed to the significant loss of altitude.
Interruption of electrical power to the multi purpose flight recorder due to water ingress removed of an important source of information used to identify safety issues.
The servo valve within the left green aileron servo was incorrectly adjusted during manufacture.
The aircraft operator did not comply with the reporting requirements of the Transport Safety Investigation Act 2003.
Fatigue cracking originated within the aircraft nose landing gear (NLG) right axle as the result of surface damage associated with grinding during manufacture, and was probably assisted in its initiation by hydrogen evolved during plating processes.
There were no specific training requirements for Robinson helicopters in Australia, such as those in Federal Aviation Administration Special Federal Aviation Regulation 73-2.
The helicopter operator's induction checklist did not include the notation of instructors’ ratings and validity periods.
The CFM56-7B engine had sustained bushing and shroud wear sufficient to cause rotor-to-stator contact, after a time in service that was less than the minimum threshold period specified by the manufacturer, for an initial inspection targeted at identifying this problem
The CFM56-7B engine design was susceptible to VSV bushing and shroud wear that can lead to internal mechanical damage and potential in-flight performance difficulties.
The flight planning requirements at page 88 of the Visual Flight Guide included a transcription error that inadvertently limited the application of the requirements of Civil Aviation Regulation 239.
The current advice in Civil Aviation Advisory Publication 5.81-1(0) Flight Crew Licensing Flight Reviews in relation to the assessment of navigation skills, represents a missed opportunity to identify a pilot's capacity to make safe and appropriate decisions during cross country flying.
There was no Australian requirement for endorsement and recurrent training conducted on Robinson Helicopter Company R22/R44 helicopters to specifically address the preconditions for, recognition of, or recovery from, low main rotor RPM.
There was a lack of assurance that informal operator supervisory and experience-based policy, procedures and practices minimised the risk of pilots operating outside the individual pilot’s level of competence.
Likely due to a training deficiency, Alliance Airlines flight crews' conduct of the Before start procedures and Pre-take-off brief review were not being performed effectively to ensure the speed selector knob was correctly set and checked, which increased the risk of a low-speed event after take-off.
Although Airservices Australia used applied operational risk assessments to high-level threats, it did not formally assess and manage the risk of specific threat scenarios. As a likely result, Airservices did not formally identify and risk manage the threat of separate aircraft concurrently carrying out the MARUB SIX standard instrument departure and a missed approach from runway 34R at Sydney Airport, even though it had been a known issue among controllers generally.
