The inspection procedures in the West Star Aviation maintenance manual supplement for extended life program Cessna 441 aircraft were inadequate to detect the progressive disbonding of the emergency exit door.
Although the operator complied with the regulatory requirements for training and experience of pilots, it had limited processes in place to ensure pilots with minimal time and experience on a new and technically different helicopter type had the opportunity to effectively consolidate their skills on the type required for conducting the operator's normal operations to pontoons.
It was common practice for the operator’s pilots to leave the controls of their helicopter, while the rotors were turning and the friction locks applied, to escort passengers to and from the helicopter.
There was often a significant number of birds located on the pontoons at Hardy Reef used by the operator. However, the operator did not have a process to systematically manage the risk of birdstrike. For example:
Although the operator had calibrated scales available for use at two of their check-in locations, they were not routinely used to ascertain actual passenger and/or baggage weights. Instead, the operator's personnel relied on passengers’ volunteered weights (without an additional allowance) and only weighed passengers when the volunteered weights were perceived to be inaccurate.
The operator’s system used to identify passengers with reduced mobility and/or required additional safety briefing information relied on passengers self-reporting a problem.
Due to multiple factors, the design of the rear left sliding door (emergency exit) on the EC120B helicopter was not simple and obvious to use unless the occupant was provided with specific instructions about how to operate the exit. In particular:
There was no requirement for operators of passenger transport flights in aircraft with six or less seats to provide passengers with a verbal briefing, or written briefing material, on the method for operating the emergency exits.
Although the operator had specified multiple methods of cross-checking fuel quantity gauge indications for its C441 fleet, there were limitations in the design, definition and/or application of these methods. These included:
The operator did not place appropriate emphasis on ensuring the continuing airworthiness of the landing gear of its GA8 fleet, although being aware of:
There were no requirements in Aeropower procedures to provide any post-training supervision for powerline operations. What supervision was provided was ineffective in identifying that a modified stringing method was being used by the pilot.
Although required by the harness instrument commonly issued by the Civil Aviation Safety Authority, the operator did not appraise shooting crews of the risks of using only a harness for restraint during low-level flight.
A harness instrument, commonly issued by the Civil Aviation Safety Authority (CASA), stated that a harness could be used instead of a seatbelt for take-off and landing. Although not intended by CASA, this instrument was easily able to be misinterpreted as indicating that a seatbelt was not required to be used during take-off and landing.
Recurrency training and drills in aircraft emergencies were not required for reissue of an aerial platform shooting permission. Some shooters last conducted training about 20 years prior, during initial issue of their permissions.
The Director of National Parks did not actively manage the risk of the aerial culling task being conducted in the Kakadu National Park, or effectively supervise the operation. As a result, an increase in the number of crew, a change in helicopter type and change of helicopter operator all progressed without requisite risk management. This exposed crew to avoidable harm during low-level aerial shooting operations.
Although the Director of National Parks’ safe operating procedures required shooters and spotters to wear helmets during aerial culling tasks, helmets were not provided or used on a routine basis.
Annex 6 to the Convention of International Civil Aviation did not mandate the fitment of flight recorders for passenger-carrying aircraft under 5,700 kg. Consequently, the determination of factors that influenced this accident, and numerous other accidents have been hampered by a lack of recorded data pertaining to the flight. This has likely resulted in important safety issues not being identified, which may remain a hazard to current and future passenger carrying operations.
There was no regulatory requirement from the Civil Aviation Safety Authority for piston‑engine aircraft to carry a carbon monoxide detector with an active warning to alert pilots to the presence of elevated levels of carbon monoxide in the cabin.
Australian civil aviation regulations did not mandate the fitment of flight recorders for passenger-carrying aircraft under 5,700 kg. Consequently, the determination of factors that influenced this accident, and other accidents have been hampered by a lack of recorded data pertaining to the flight. This has likely resulted in the non‑identification of safety issues, which continue to present a hazard to current and future passenger-carrying operations.
Response by the Civil Aviation Safety Authority
Although detectors were not required to be fitted to their aircraft, Sydney Seaplanes had no mechanism for monitoring the serviceability of the carbon monoxide detectors.
