Australia

Loss of control during initial climb following a bird strike.

From the evidence available, the following findings are made with respect to the loss of control event involving Piper Aircraft Corporation PA-31-350 aircraft registered VH-ZGZ and should not be read as apportioning blame or liability to any particular organisation or individual.
Contributing safety factors:
• The aircraft diverged left from a steady, controlled descent and entered a steep, left spiral descent from which recovery was not achieved.
Other safety factors:
• The dark and very likely cloudy conditions that existed in the area where the aircraft suddenly diverged from its flight path meant that recovery to normal flight could only have been achieved by sole reference to the aircraft’s flight instruments. The difficulty associated with such a task when the aircraft was in a steep descent was likely to have been significant.

ATSB did not conduct any investigations on this event.

Contributing factors:
• A line of thunderstorms crossed the aircraft’s intended track.
• The aircraft was operating in the vicinity of thunderstorm cells.
• In circumstances that could not be determined, the aircraft’s load limits were exceeded, causing structural failure of the airframe.
Other safety factors:
• Air traffic control procedures, did not require the SIGMET information to be passed to the aircraft.
• There were shortcomings in the Airservices Australia Hazard Alert procedures and guidelines for assessing SIGMET information.
• Air traffic control procedures for the dissemination of SIGMET information contained in the Aeronautical Information Publication were inconsistent with procedures contained in International Civil Aviation Organization (ICAO) Doc. 4444 and ICAO Doc. 7030.
Other key findings:
• The aircraft was not equipped with weather radar or lightning strike detection systems.
• The pilot did not make any request for additional information regarding the weather to air traffic services.
• The pilot in command was occupying the right cockpit seat and the observer- pilot the left cockpit seat at the time of the breakup, but that arrangement was not considered to have influenced the development of the accident.

Findings:
• There were no indications prior to, or during the flight, of problems with any aircraft systems that may have contributed to the circumstances of the occurrence.
• The pilot continued flight into forecast and known icing conditions in an aircraft not approved for flight in icing conditions.
• The global navigation satellite constellation was operating normally.
• The pilot did not comply with the requirements of the published instrument approach procedure.
• The pilot was known, by his Chief Pilot and others, to adopt non-standard approach procedures to establish his aircraft clear of cloud when adverse weather conditions existed at Mount Hotham.
• The pilot may have been experiencing self-imposed and external pressures to attempt a landing at Mount Hotham.
• Terrain features would have been difficult to identify due to a heavy layer of snow, poor visibility, low cloud, continuing heavy snowfall, drizzle, sleet and approaching end of daylight.
• The pilot’s attitude, operational and compliance practices had been of concern to some Airservices’ staff.
• The operator’s operational and compliance history was recorded by CASA as being of concern, and as a result CASA staff continued to monitor the operator. However, formal surveillance of the operator in the preceding two years had not identified any significant operational issues.
Significant factors:
• The weather conditions at the time of the occurrence were extreme.
• The extreme weather conditions were conducive to visual illusions associated with a flat light phenomenon.
• The pilot did not comply with the requirements of flight under either the instrument flight rules (IFR) or the visual flight rules (VFR).
• The pilot did not comply with the requirements of the published instrument approach procedure and flew the aircraft at an altitude that did not ensure terrain clearance.
• The aircraft accident was consistent with controlled flight into terrain.

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.

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.

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.