Australia

The pilot in command did not plan the flight in accordance with the existing regulatory and operator requirements, precluding a full understanding and management of the potential hazards affecting the flight. The flight crew did not source the most recent Norfolk Island Airport forecast, or seek and apply other relevant weather and other information at the most relevant stage of the flight to fully inform their decision of whether to continue the flight to the island, or to divert to another destination. The flight crew’s delayed awareness of the deteriorating weather at Norfolk Island combined with incomplete flight planning to influence the decision to continue to the island, rather than divert to a suitable alternate.

From the evidence available, the following findings are made with respect to the collision with terrain involving Piper Aircraft Corp. PA-31-35 Chieftain, registered VH-OPC, 3 km north of Bathurst Airport on 7 November 2008 and should not be read as apportioning blame or liability to any particular organisation or individual.
Contributing safety factors:
• The aircraft descended at a steep angle before impacting the ground at high speed, consistent with uncontrolled flight into terrain.
Other key findings:
• Based on analysis of the available information, an airworthiness issue was considered unlikely to be a contributing factor to this accident.
• The investigation was unable to establish why the aircraft collided with terrain; however, pilot spatial disorientation or pilot incapacitation could not be discounted.

Following a review of the available evidence covering:
• Witness information,
• The pilot's fatigue and health,
• The airworthiness of the aircraft,
• Aircraft fuel,
• The weather affecting the flight, and
• The aircraft’s loading and weight and balance,
The investigation was unable to identify any factors that may have contributed to the accident. From the evidence available, the following findings are made with respect to the missing aircraft at Buckingham Bay, Northern Territory on 16 October 2008 involving Gippsland Aeronautics GA8 Airvan aircraft, registered VH-WRT. They should not be read as apportioning blame or liability to any organisation or individual. No contributing safety factors were identified.
Other safety factors:
• The main vertical net and the throwover net were not used to restrain the cargo.
• The full jerry cans were not secured in the aircraft cabin.
• At the time of departure, the aircraft’s centre of gravity (c.g) was probably to the rear of the permitted c.g limit that was published in the Aircraft Flight Manual.
• There was no record that the pilot lodged a flight notification for the flight with Airservices Australia.

Engine failure for unknown reasons.

From the evidence available, the following findings are made with respect to the fuel starvation event and should not be read as apportioning blame or liability to any particular organisation or individual.
- The pilot did not monitor outboard fuel tank quantity during the flight.
- The pilot incorrectly diagnosed the engine power losses.
- The aircraft was not in the correct configuration for the forced landing.

Contributing Safety Factors:
- It was very likely that the aircraft’s alternating current electrical power system was not energised at any time during the flight.
- It was very likely that the aircraft became airborne without a functioning primary attitude reference or autopilot that, combined with the added workload of managing the ‘slight technical fault’, led to pilot spatial disorientation and subsequent loss of control.
Other Safety Factors:
- The pilot’s Metro III endorsement training was not conducted in accordance with the operator’s approved training and checking manual, with the result that the pilot’s competence and ultimately, safety of the operation could not be assured. [Significant safety issue].
- The chief pilot was performing the duties and responsibilities of several key positions in the operator’s organisational structure, increasing the risk of omissions in the operator’s training and checking requirements.
- The conduct of the flight single-pilot increased the risk of errors of omission, such as not turning on or noticing the failure of aircraft items and systems, or complying with directions.

Contributing safety factors:
• The aircraft probably entered an area of weather that deteriorated below visual meteorological conditions and for which the pilot was not experienced or qualified.
• The pilot probably became unsure of his position in poor visibility, leading to controlled flight into terrain, fatally injuring the pilot and destroying the aircraft.
Other safety factors:
• The aircraft had not been configured for poor visibility operations, possibly increasing the pilot’s difficulty in navigating.
• The pilot did not submit any form of flight notification such as a SARTIME or Flight Note, as required for a flight in a designated remote area, resulting in a delay to the search and rescue response.
• The operator did not have procedures to provide assurance that a search and rescue would be initiated in a timely way if one of their aircraft did not arrive at the planned destination. [Safety issue]
• As a result of damage to the emergency locator beacon antenna, the beacon did not alert search and rescue organisations to the aircraft accident.

Structural failure and damage:
From the detailed examination and study of the aircraft wreckage undertaken by ATSB investigation staff, it was evident that all principal structural failures had occurred under gross overstress conditions i.e. stresses significantly in excess of the physical strength of the respective structures. The examination found no evidence of pre-existing cracking, damage or material degradation that could have appreciably reduced the strength of the failed sections, nor was there any indication that the original manufacture, maintenance or repair processes carried out on the aircraft were in any way contributory to the failures sustained.

Breakup sequence:
From the localised deformation associated with the spar failures, it was evident that the aircraft had sustained a large negative (downward) loading on the wing structure. That downward load resulted in the localised bending failure of the wing around the station 145 position (145” outboard of the aircraft centreline). The symmetry of both wing failures and the absence of axial twisting within the fuselage section suggested that the load encountered was sudden and well in excess of the ultimate strength of the wing structure. Based upon the witness marks on both wing under-surfaces and the crushing and paint transfer along the leading edges of the horizontal stabilisers, it was concluded that after separating from the inboard structure, both wings had moved aft in an axial twisting and rotating fashion; simultaneously impacting the leading edges of both horizontal tailplanes. Forces imparted into the empennage structure from that impact subsequently produced the rearward separation of the complete empennage from the fuselage. The loss of the left engine nacelle fairing was likely brought about through an impact with a section of wing leading edge as it rotated under and to the rear. The damage sustained by all of the aircraft‟s control surfaces was consistent with failure and separation from their respective primary structure under overstress conditions associated with the breakup of the aircraft. There was no evidence of cyclic or oscillatory movement of the surfaces before separation that might have suggested the contribution of an aerodynamic flutter effects.

Findings
The following statements are a summary of the verified findings made during the progress of the aircraft wreckage structural examination and analysis:
- All principal failures within the aircraft wings, tailplanes and empennage had occurred as a result of exposure to gross overstress conditions.
- The damage sustained by the aircraft wreckage was consistent with the aircraft having sustained multiple in-flight structural failures.
- The damage sustained by the aircraft wreckage was consistent with the structural failure sequence being initiated by the symmetric, downward bending failure of both wing sections, outboard of the engine nacelles.
- Breakup and separation of the empennage was consistent with having been initiated by impact of the separated outboard wings with the leading edges of the horizontal stabilisers.
- There was no evidence of material or manufacturing abnormalities within the aircraft structure that could be implicated in the failures and breakup sustained.
- There was no evidence of service-related degradation mechanisms (such as corrosion, fatigue cracking or environmental cracking) having affected the aircraft structure in the areas of failure.

From the evidence available, the investigation revealed that two major system components had failed which could have prevented the Beechcraft Super King Air 200 landing gear from properly retracting after takeoff. The following findings with respect to those failed landing gear system components should not be read as apportioning blame or liability to any particular organisation or individual.
Contributing safety factors:
• The left torque tube support bearing had not been lubricated and had seized due to the accumulation of dirt and grit contaminants that had migrated from the external service environment and into the bearing.
• The geared components within the right main landing gear actuator prematurely failed.
Other safety factors:
• The aircraft manufacturer’s maintenance manual contained insufficient instruction or guidance for operators and maintainers of Super King Air 200 aircraft for the lubrication of the landing gear torque tube support bearings.
Other key findings:
• Both component assemblies were integral to the function and normal operation of the Super King Air 200 mechanical landing gear system. A break down of either component assembly would have prevented any attempt by the pilot to retract or extend the aircraft’s main landing gear. However, while either failure could have produced the landing gear difficulties sustained, the investigation was not able to determine which mechanism was the principal contributor to the event.
• The investigation was unable to conclusively establish why the geared components within the right main landing gear actuator had prematurely failed.
• The lower thrust bearing within the right main landing gear actuator had been correctly installed.