Oceania

Contributing factors relating to occurrence events and individual actions:
- The crew commenced the Lockhart River Runway 12 RNAV (GNSS) approach, even though the crew were aware that the copilot did not have the appropriate endorsement and had limited experience to conduct this type of instrument approach.
- The descent speeds, approach speeds and rate of descent were greater than those specified for the aircraft in the Transair Operations Manual. The speeds and rate of descent also exceeded those appropriate for establishing a stabilised approach.
- During the approach, the aircraft descended below the segment minimum safe altitude for the aircraft's position on the approach.
- The aircraft's high rate of descent, and the descent below the segment minimum safe altitude, were not detected and/or corrected by the crew before the aircraft collided with terrain.
- The accident was almost certainly the result of controlled flight into terrain.

Contributing factors relating to local conditions:
- The crew probably experienced a very high workload during the approach.
- The crew probably lost situational awareness about the aircraft's position along the approach.
- The pilot in command had a previous history of conducting RNAV (GNSS) approaches with crew without appropriate endorsements, and operating the aircraft at speeds higher than those specified in the Transair Operations Manual.
- The Lockhart River Runway 12 RNAV (GNSS) approach probably created higher pilot workload and reduced position situational awareness for the crew compared with most other instrument approaches. This was due to the lack of distance referencing to the missed approach point throughout the approach, and the longer than optimum final approach segment with three altitude limiting steps.
- The copilot had no formal training and limited experience to act effectively as a crew member during a Lockhart River Runway 12 RNAV (GNSS) approach.

Contributing factors relating to Transair processes:
- Transair's flight crew training program had significant limitations, such as superficial or incomplete ground-based instruction during endorsement training, no formal training for new pilots in the operational use of GPS, no structured training on minimising the risk of controlled flight into terrain, and no structured training in crew resource management and operating effectively in a multi-crew environment. (Safety Issue)
- Transair's processes for supervising the standard of flight operations at the Cairns base had significant limitations, such as not using an independent approved check pilot to review operations, reliance on passive measures to detect problems, and no defined processes for selecting and monitoring the performance of the base manager. (Safety Issue)
- Transair's standard operating procedures for conducting instrument approaches had significant limitations, such as not providing clear guidance on approach speeds, not providing guidance for when to select aircraft configuration changes during an approach, no clear criteria for a stabilised approach, and no standardised phraseology for challenging safety-critical decisions and actions by other crew members. (Safety Issue)
- Transair had not installed a terrain awareness and warning system, such as an enhanced ground proximity warning system, in VH-TFU.
- Transair's organisational structure, and the limited responsibilities given to non-management personnel, resulted in high work demands on the chief pilot. It also resulted in a lack of independent evaluation of training and checking, and created disincentives and restricted opportunities within Transair to report safety concerns with management decision making. (Safety Issue)
- Transair did not have a structured process for proactively managing safety related risks associated with its flight operations. (Safety Issue)
- Transair's chief pilot did not demonstrate a high level of commitment to safety. (Safety Issue)

Contributing factors relating to the Civil Aviation Safety Authority processes:
- CASA did not provide sufficient guidance to its inspectors to enable them to effectively and consistently evaluate several key aspects of operator management systems. These aspects included evaluating organisational structure and staff resources, evaluating the suitability of key personnel, evaluating organisational change, and evaluating risk management processes. (Safety Issue)
- CASA did not require operators to conduct structured and/or comprehensive risk assessments, or conduct such assessments itself, when evaluating applications for the initial issue or subsequent variation of an Air Operator's Certificate. (Safety Issue)

Other factors relating to local conditions:
- There was a significant potential for crew resource management problems within the crew in high workload situations, given that there was a high trans-cockpit authority gradient and neither pilot had previously demonstrated a high level of crew resource management skills.
- The pilots' endorsements, clearance to line operations, and route checks did not meet all the relevant regulatory and operations manual requirements to conduct RPT flights on the Metro aircraft.
- Some cockpit displays and annunciators relevant to conducting an instrument approach were in a sub-optimal position in VH-TFU for useability or attracting the attention of both pilots.

Other factors relating to instruments approaches:
- Based on the available evidence, the Lockhart River Runway 12 RNAV (GNSS) approach design resulted in mode 2A ground proximity warning system alerts and warnings when flown on the recommended profile or at the segment minimum safe altitudes. (Safety Issue)
- The Australian convention for waypoint names in RNAV (GNSS) approaches did not maximise the ability to discriminate between waypoint names on the aircraft global positioning system display and/or on the approach chart. (Safety Issue)
- There were several design aspects of the Jeppesen RNAV (GNSS) approach charts that could lead to pilot confusion or reduction in situational awareness. These included limited reference regarding the 'distance to run' to the missed approach point, mismatches in the vertical alignment of the plan-view and profile-view on charts such as that for the Lockhart River runway 12 approach, use of the same font size and type for waypoint names and 'NM' [nautical miles], and not depicting the offset in degrees between the final approach track and the runway centreline. (Safety Issue)
- Jeppesen instrument approach charts depicted coloured contours on the plan-view of approach charts based on the maximum height of terrain relative to the airfield only, rather than also considering terrain that increases the final approach or missed approach procedure gradient to be steeper than the optimum. Jeppesen instrument approach charts did not depict the terrain profile on the profile-view although the segment minimum safe altitudes were depicted. (Safety Issue)
- Airservices Australia's instrument approach charts did not depict the terrain contours on the plan-view. They also did not depict the terrain profile on the profile-view, although the segment minimum safe altitudes were depicted. (Safety Issue)

Other factors relating to Transair processes:
- Transair's flight crew proficiency checking program had significant limitations, such as the frequency of proficiency checks and the lack of appropriate approvals of many of the pilots conducting proficiency checks. (Safety Issue)
- The Transair Operations Manual was distributed to company pilots in a difficult to use electronic format, resulting in pilots minimising use of the manual. (Safety Issue) Other factors relating to regulatory requirements and guidance
- Although CASA released a discussion paper in 2000, and further development had occurred since then, there was no regulatory requirement for initial or recurrent crew resource management training for RPT operators. (Safety Issue)
- There was no regulatory requirement for flight crew undergoing a type rating on a multi-crew aircraft to be trained in procedures for crew incapacitation and crew coordination, including allocation of pilot tasks, crew cooperation and use of checklists. This was required by ICAO Annex 1 to which Australia had notified a difference. (Safety Issue)
- The regulatory requirements concerning crew qualifications during the conduct of instrument approaches in a multi-crew RPT operation was potentially ambiguous as to whether all crew members were required to be qualified to conduct the type of approach being carried out. (Safety Issue)
- CASA's guidance material provided to operators about the structure and content of an operations manual was not as comprehensive as that provided by ICAO in areas such as multi-crew procedures and stabilised approach criteria. (Safety Issue)
- Although CASA released a discussion paper in 2000, and further development and publicity had occurred since then, there was no regulatory requirement for RPT operators to have a safety management system. (Safety Issue)
- There was no regulatory requirement for instrument approach charts to include coloured contours to depict terrain. This was required by a standard in ICAO Annex 4 in certain situations. Australia had not notified a difference to the standard. (Safety Issue)
- There was no regulatory requirement for multi-crew RPT aircraft to be fitted with a serviceable autopilot. (Safety Issue)

Other factors relating to Civil Aviation Safety Authority processes:
- CASA's oversight of Transair, in relation to the approval of Air Operator's Certificate variations and the conduct of surveillance, was sometimes inconsistent with CASA's policies, procedures and guidelines.
- CASA did not have a systematic process for determining the relative risk levels of airline operators. (Safety Issue)
- CASA's process for evaluating an operations manual did not consider the useability of the manual, particularly manuals in electronic format. (Safety Issue)
- CASA's process for accepting an instrument approach did not involve a systematic risk assessment of pilot workload and other potential hazards, including activation of a ground proximity warning system. (Safety Issue) Other key findings An 'other key finding' is defined as any finding, other than that associated with safety factors, considered important to include in an investigation report. Such findings may resolve ambiguity or controversy, describe possible scenarios or safety factors when firm safety factor findings were not able to be made, or note events or conditions which 'saved the day' or played an important role in reducing the risk associated with an occurrence.
- It was very likely that both crew members were using RNAV (GNSS) approach charts produced by Jeppesen.
- The cockpit voice recorder did not function as intended due to an internal fault that had developed sometime before the accident flight and that was not discovered or diagnosed by flight crew or maintenance personnel.
- There was no evidence to indicate that the GPWS did not function as designed.
- There would have been insufficient time for the crew to effectively respond to the GPWS alert and warnings that were probably annunciated during the final 5 seconds prior to impact with terrain.

Findings are listed in order of development and not in order of priority.
- The flight crew was appropriately licensed and rated for the aircraft, and qualified for the flight.
- The captain was experienced on the type and the operation, and approved as a line training captain, while the FO was recently trained and not very experienced on the type.
- The aircraft had a valid Certificate of Airworthiness and records indicated that it had been maintained in accordance with its airworthiness requirements. There were no relevant deferred
maintenance items prior to dispatch of the accident flight.
- Although the aircraft had been refuelled in one tank only, it probably took off with the fuel balanced within limits.
- Some fuel imbalance led the captain to decide to carry out further fuel balancing while the aircraft was in cruising flight.
- The captain’s instructions to the FO while carrying out fuel balancing resulted in the aircraft being flown at a large sideslip angle by the use of the rudder trim control while the autopilot was engaged.
- The FO’s reluctance to challenge the captain’s instruction may have been due to his inexperience and underdeveloped CRM skills.
- The autopilot probably disengaged automatically because a servo reached its torque limit, allowing the aircraft to roll and dive abruptly as a result of the applied rudder trim.
- The crew was unable to recover control from the ensuing spiral dive before airspeed and g limits were grossly exceeded, resulting in the structural failure and in-flight break-up of the aircraft.
- The in-flight fire which occurred was a result of the break-up, and not a precursor to it.
- The applied rudder trim probably contributed to the crew’s inability to recover control of the aircraft.
- The crew’s other control inputs to recover from the spiral dive were not optimal, and contributed to the structural failure of the aircraft.
- The flying conditions of a dark night with cloud cover below probably hindered the crew’s early perception of the developing upset.
- The AFM limitation on use of the autopilot above 20 000 ft should have led to the crew disconnecting it when climbing the aircraft above that altitude.
- The crew’s non-observance of this autopilot limitation probably did not affect its performance, or its automatic disengagement.
- If the aircraft had been manually flown during the fuel-balancing manoeuvre, the upset would probably have not occurred.
- The operator should detail the in-flight fuel balancing procedure as a written SOP for its Metro aircraft operation.
- The AFM for the SA 226/227 family of aircraft should include a limitation and warning that the autopilot must be disconnected while in-flight fuel balancing is done, and should include a procedure for in-flight fuel balancing.

For reasons that could not be determined, the aircraft commenced a slight left angle of bank and drifted left after lift-off at a height from which the pilot was unable to recover prior to striking trees to the left of the runway.

Controlled flight into terrain.

Significant factors:
1. The pilot was not aware that the aircraft had diverged from the intended track.
2. The route flown did not pass over any ground-based navigation aids.
3. The sector controller did not advise the pilot of the divergence from the cleared track.
4. The sector controller twice cancelled the route adherence monitoring alerts without confirming the pilot’s tracking intentions.
5. Cloud precluded the pilot from detecting, by external visual cues, that the aircraft was not flying the intended track.
6. The pilot commenced the approach at an incorrect location.
7. The aircraft’s radio altimeter did not provide the pilot with an adequate defence to avoid collision with terrain.
8. The aircraft was not fitted with a terrain awareness warning system (TAWS).

The trajectory analysis provided the ATSB with a high degree of confidence with respect to the aircraft altitude and speed at the time of the in-flight breakup. The aircraft’s speed could have readily accelerated to Vne during a rapid descent from the nominated cruise altitude of 8,500 ft to the break-up altitude of around 3,150 ft. At such a speed, a relatively small control input force or gusts encountered in the longitudinal (pitch) axis of the aircraft could have resulted in the symmetrical downward wing overloading and failure that occurred. There is no compelling evidence to support any one reason for the departure of the aircraft from the cruise altitude into a high speed dive type situation. However, there are a number of factors that provide some weight to the possibility of a flight upset related to operation of the autopilot. These factors include:
• The lack of any reference in the operations manual to the installation of a Bendix FCS-810 autopilot in LST and the lack of information in the operations manual on the operation of the FCS-810 autopilot
• The pilot’s relative inexperience in the operation of the particular autopilot system fitted to LST
• The operating characteristics of the autopilot system fitted to LST
• The illegible nature of the Aircraft Flight Manual supplement pertaining to the limitations and operating procedures for the autopilot system fitted to LST
• The autopilot controller pitch command wheel being found at the accident site in the maximum nose-down position
• Both elevator trim tabs being found at the accident site at or close to the maximum nose-down trim position. However, it is not possible to discount other explanations for the departure from cruise flight, including a runaway pitch-trim condition, pilot incapacitation, the effects of mountain waves and/or severe turbulence, or a combination of any of the above. On the evidence available to the investigation, it was not possible to conclusively determine the circumstances that led to the aircraft descending at speed to the altitude at which the in-flight breakup occurred.

The following factors were identified:
1. The pilots of CYC were conducting in-flight familiarization training using the emergency power lever. That procedure was not contained in the aircraft manufacturer's pilot operating handbook.
2. The engine manufacturer's documentation contained information on the use of the emergency power lever, which did not preclude the use of the emergency power lever for in-flight familiarization training.
3. The engine sustained a flameout at an altitude above mean sea level from which reignition of the engine was not successfully completed.
4. Erosion of the first-stage compressor blades would have reduced the aerodynamic efficiency of the compressor blades.

Without the aircraft wreckage or more detailed information regarding the behaviour of the aircraft in the final stages of the flight, there was insufficient information available to allow any conclusion to be drawn about the development of the accident. Many possible explanations exist. The fact that no radio transmission was received from the aircraft around the time radar contact was lost could indicate that the aircraft was involved in a sudden or unexpected event at that time that prevented the crew from operating the radio. The speed regime of the aircraft during the last recorded data points indicated that airframe failure due to aerodynamic overload was unlikely. The nature of the items from the aircraft that were recovered from the ocean surface indicated that the aircraft cabin had been ruptured during the accident sequence.