Pilots must learn to recover from an incipient spin and demonstrate recovery from the manoeuvre during flight tests. Evidence suggests that in some cases, this training is being performed in aircraft that are not approved for intentional spins. Depending on the aircraft type, the manufacturer may not have specified whether that restriction applies to an incipient spin or only a developed spin.

What happened

On 26 September 2017, an instructor and student conducted a training flight in a Diamond Aircraft Industries DA40 aircraft, registered VH-MPM, from Archerfield Airport, Queensland. The purpose of the flight was a simulated Recreational Pilot Licence flight test to prepare the student for an upcoming flight test.

Factors uncovered during the investigation

The ATSB identified concerns relating to the conduct of incipient spin training in aircraft types not approved for intentional spinning.

The DA40 aircraft type is certified to recover from a one-turn spin or a three-second spin (whichever takes longer), and is not proven or certified to be recoverable from a longer spin. The aircraft’s manuals state that intentional spins are prohibited. During the ATSB investigation, the aircraft manufacturer clarified that this limitation prohibits any action that is intended to induce a spin, even if the aircraft is immediately recovered.

Aircraft types with similar limitations are currently in use throughout the world for flying training. In Australia, the Civil Aviation Safety Authority requires the demonstration of recovery from an incipient spin during flight tests. However, there is no clear and consistent definition of the point at which a manoeuvre becomes a spin (or incipient spin) for the purposes of flying training.

Crucially, the ATSB found that there can be varying interpretations of an ‘incipient spin’, and this has led to aircraft not approved for intentional spins being used for incipient spin training and assessment.

Safety advisory notice

: Operating an aircraft within the stated limitations is essential to the safe conduct of a flight. Training organisations are required to conduct incipient spin recovery training, which includes intentionally inducing a spin and recovering before it fully develops. Some organisations may be conducting this training in aircraft not approved for intentional spinning. The ATSB advises these training organisations to clarify with aircraft manufacturers the extent to which the intentional entry into the early stages of a spin, including an incipient spin, is permissible.

The standard industry practice of re-using self-locking nuts on Robinson helicopters may inadvertently result in the omission to replace MS21042L or NAS1291-series nuts with D210-series corrosion resistant (CRES) nuts on critical fasteners.

Safety advisory notice

The Australian Transport Safety Bureau advises all maintenance personnel for Robinson helicopters to ensure that before re-using a self-locking nut, that the correct part number is fitted, and that the D210-series corrosion-resistant nuts are used for reassembly of critical fasteners in accordance with the Robinson Helicopter Company instructions for continued airworthiness.

What happened

On 2 August 2017, a Robinson R22 Beta helicopter impacted terrain about 7 km north-north-west of Cloncurry Airport, Queensland. The pilot, who was the only person on board, was fatally injured and the helicopter was destroyed. The accident flight was the first commercial flight post the helicopter’s second 2,200-hour overhaul.

Finding of increased risk

During the review of on-site accident photographs to verify the flight control joints, the ATSB noted an anomaly with the helicopter’s bellcrank (part number A958-1) in the cyclic control system. The fastener, which attached the horizontal push-pull tube (part number A121-1) to the bellcrank, was missing. The bellcrank’s remaining fasteners were all attached. The bellcrank and missing fastener bolt were recovered, but the reason for the separation of the nut from the bolt has not yet been determined.

The missing fastener was part of the longitudinal cyclic pitch control system, which controls the fore-aft tilt of the main rotor disc (Figure 1).

Figure 1: Robinson R22 helicopter cyclic control system

Robinson R22 helicopter cyclic control system schematic: The horizontal push-pull tube, bellcrank, vertical push-pull tubes and jackshaft are highlighted in yellow. The location of the missing fastener is highlighted in red. Source: Robinson Helicopter Company, modified by ATSB

The examination of the bellcrank found that the bolt-holes for the missing fastener exhibited heat damage different to that of the bolt-holes for the remaining fasteners (Figure 2). In addition, the deformation of the bellcrank prevented the installation of a bolt where the fastener was missing, but did not prevent the removal of the remaining fasteners. This indicated that the bolt was not in-situ at the time of the post-impact fire.

Figure 2: Comparison of the bellcrank bolt-holes

Left: bolt-hole for the missing fastener. Right: bolt-hole for a removed fastener. Source: ATSB

Re-use of self-locking nuts

Cracking from hydrogen embrittlement of the type of nuts fitted to Robinson helicopters has been previously identified.^[1] In October 2014, the Robinson Helicopter Company (RHC) published service letters for the R22 (SL‑64), R44 (SL-50) and R66 (SL-09) helicopters on the subject of D210 Corrosion-Resistant (CRES) Nuts. The service letters stated that, whenever maintenance that involves the disassembly and reassembly of a critical fastener is performed, the MS21042L or NAS1291 nut should be replaced with a D210-series nut.^[2] The R22 maintenance manual was amended in October 2014 to incorporate what was stated in SL-64. For specific instances of cracked nuts, RHC have published service bulletins for their replacement within a compliance period.^[3]

The R22-series maintenance manual included the following information under section 1.300 Fastener Torque Requirements:

D. Critical Fastener: A critical fastener is one which, if removed or lost, would jeopardize safe operation of the helicopter. This includes joints in the primary control system, and non-fail-safe structural joints in the airframe, landing gear, and drive system.

CAUTION: D210-series nuts, which supersede MS21042L-series and NAS1291-series nuts, are required on critical fasteners.

In the course of interviewing personnel employed by the maintenance organisation, the ATSB noted a low level of awareness of the need to replace MS21042L/NAS1291-series nuts with the D210-series nuts when critical fasteners were reassembled. In accordance with the R22 maintenance manual, critical fasteners include a self-locking nut in their assembly. It is a standard practice within sectors of the aviation industry to re-use self-locking nuts provided the nut cannot be turned onto the bolt thread by hand and the published torque value for the fastener is achieved.

During the course of the investigation the ATSB spoke with another maintenance organisation, who reported they employ the same practice of re-using self-locking nuts, and the helicopter manufacturer confirmed this was an acceptable practice. The United States National Transportation Safety Board reported on this practice as accepted by the manufacturers of light helicopters in their aircraft accident report AAR-13/01.^[4] They noted that guidance on the re-use of self-locking nuts was provided by Eurocopter (now Airbus Helicopters), Sikorsky, Bell and the United States Federal Aviation Administration.

In December 2018, the ATSB received the accident helicopter’s jackshaft, which had the fasteners attached. The jackshaft was one of a number of parts within the flight control system that was disassembled and sent for non-destructive inspection during the 2,200-hour overhaul. The bellcrank was not subject to non-destructive inspection and therefore not required to be disassembled. In late January 2019, the ATSB completed semi-quantitative chemical analysis of the nuts fitted to the jackshaft and found they were consistent with a carbon/alloy steel, and therefore not consistent with D210-series stainless steel corrosion-resistant nuts. The nuts fitted to the jackshaft had similar markings to the nuts fitted to the bellcrank, which were consistent with MS21042L/NAS1291-series nuts.

At the time of the reassembly of the accident helicopter, the current R22 Illustrated Parts Catalog detailed the part number D210-4 for the nuts fitted to the jackshaft, and RHC confirmed there was no alternate part number to the D210-series nuts.

In consideration of the evidence, the ATSB concluded that the industry practice of re-use of self‑locking nuts on Robinson helicopters may result in the omission to install D210-series nuts when critical fasteners are reassembled.

The ATSB advises that this finding of increased risk applies to all approved maintenance organisations for Robinson helicopters and at present has not been identified as a contributing factor to this accident.

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1. Refer to Civil Aviation Safety Authority Airworthiness Bulletin: 14-002, Cracked MS 21042 / NAS 1291 – Series Nuts – Hydrogen Embrittlement; and Transport Canada Civil Aviation Safety Alert 2013-04: Defective Standard Aircraft Hardware – Self-Locking Nuts – MS21042 and NAS11291.
2. In August 2018, Textron published an information letter to owners and operators of Bell helicopters to inform them of the supersession of MS21042 and NAS1291 series nuts in response to reports of cracking from hydrogen embrittlement.
3. For example, R44 Service Bulletin SB-88: Landing Gear Attach Nuts, required the replacement of NAS1291-7 nuts with D210-7 within 100 flight hours or by 28 February 2015.
4. National Transportation Safety Board, 2013. Loss of Control, Sundance Helicopters, Inc., Eurocopter AS350-B2, N37SH, Near Las Vegas, Nevada, December 7, 2011. Aircraft accident report NTSB/AAR-13/01. Washington, US.

Why we have done this report

Occurrences involving aircraft striking wildlife, particularly birds, continue to be the most common aviation occurrence reported to the ATSB. Strikes with birds are a potential safety risk and present a significant economic risk for aerodrome and aircraft operators. The aim of the ATSB’s statistical report series is to provide information back to pilots, aerodrome and aircraft operators, regulators, and other aviation industry participants to assist them with managing the risks associated with bird and animal strikes. This report updates the last edition (published in 2016) with data from 2016 – 2017.

What the ATSB found

Between 2008 and 2017, there were 16,626 confirmed birdstrikes reported to the ATSB. The number of reported birdstrikes has increased in recent years, with 2017 having the highest on record with 1,921. Despite being a high frequency occurrence, birdstrikes rarely result in aircraft damage or injuries. Of the 16,626 birdstrikes in this reporting period, 99.8 per cent were classified as incidents, while 19 (~0.1 per cent) were classified as accidents and another five (~0.03 per cent) as serious incidents. Nine birdstrikes, or approximately 0.05 per cent of the birdstrikes in the ten years, resulted in minor injuries to pilots or passengers. There were no reported serious injuries or fatalities associated with a birdstrike occurrence in the ten-year period.

Domestic high-capacity aircraft were those most often involved in birdstrikes, and the birdstrike rate per aircraft movement for these aircraft was significantly higher than all other categories. Both the number and rate of birdstrikes per 10,000 movements in high-capacity operations have increased in the past two years 2016 – 2017. In contrast, the number of birdstrikes in low-capacity operations and general aviation has remained relatively consistent in the most recent two years.

The number of birdstrikes involving a bird ingested into an engine in high-capacity air transport operations has risen in recent years with about one in ten birdstrikes for turbofan aircraft involving a bird ingested into an engine. Additionally, over the ten-year reporting period, there have been 11 occurrences involving one or more birds ingested into two engines of turbofan-powered aircraft.

The five most commonly struck flying animals in the 2016 to 2017 period were flying foxes, galahs, magpies, and ‘bats’ (many of which were likely to be flying foxes) and plovers.

Compared to birdstrikes, non-flying animal strikes are relatively rare, with 396 animal strikes reported to the ATSB between 2008 and 2017. The most common animals involved were hares, rabbits, kangaroos, wallabies, and foxes. Damaging animal strikes mostly involved kangaroos and wallabies.

Safety message

Australian aviation wildlife strike statistics provide a reminder to everyone involved in the operation of aircraft and aerodromes to be aware of the hazards posed to aircraft by birds and non-flying animals. The growth of reporting to the ATSB over the last 10 years has helped to understand better the nature of birdstrikes, and what and where the major safety risks lie. As such, timely and thorough reporting of birdstrikes is paramount. This assists the aviation industry to manage better their safety risk. Over the ten years from 2008 to 2017, about 40 per cent of all birdstrikes reported to the ATSB contained no species information. The more detailed the information is provided to the ATSB, the more accurate and useful reports like this one will be.

What is wake turbulence

For fixed-wing aircraft, wake turbulence is the combined effect of jet blast or propeller wash with wake vortices. Wake vortices are the primary contributor to wake turbulence. The initial strength of the vortices is primarily dependent upon the generating aircraft’s speed, weight and wingspan. These vortices decay with time and largely become non‑hazardous—depending on atmospheric conditions—within several minutes.

The wake vortices can affect following aircraft in a similar way to flying through weather-related turbulence. More specifically, aircraft encountering wake turbulence may experience an induced roll, which can increase safety risk, especially during phases of flight close to ground such as arrivals and departures. The risk of an injury resulting from a wake turbulence encounter is higher for cabin crew than passengers, who are generally secured in their seats earlier during arrivals.

To minimise the risk to safety associated with wake turbulence, air traffic control separates aircraft arriving or departing from an airport using wake turbulence separation standards. These are time and/or distance‑based measures that limit the separation of leading and following aircraft and are designed to reduce the likelihood and severity of wake turbulence occurrences. These standards are not applicable to parallel runways which are separated by more than 760 m. As a result, they do not apply during parallel runway operations at Sydney Kingsford Smith International Airport (Sydney Airport), where the parallel runways are separated by around 1,000 m.

The analyses in this investigation only includes encounters with wake turbulence, primarily reported by aircrew, that have been classified as an occurrence.^[1] Generally, they were reported to have resulted in a missed approach or go‑around, control issues for the aircraft, a warning activation, and/or an injury.

Why the ATSB conducted this research

In 2016, through routine monitoring of safety occurrence data, the ATSB identified a potential safety issue regarding the high proportion of wake turbulence occurrences at Sydney Airport.

To identify the contributing factors to this higher rate of occurrences at Sydney, and the level of safety risk of wake turbulence occurrences at the airport, the ATSB initiated an Aviation Research investigation under the Transport Safety Investigation Act 2003.

What the ATSB found

In Australia, between 2012 and 2016, 179 wake turbulence occurrences were reported to the ATSB, with 78 of these occurring at Sydney Airport. In addition to its high proportion of wake turbulence occurrences, seven of the eight minor injuries reported as being a result of a wake turbulence occurrences were at Sydney. Further, when compared with the combined data from other major Australian airports (Adelaide, Brisbane, Melbourne and Perth), an aircraft was more likely to have a missed approach or go‑around, a ground proximity alert, or have control issues following a wake turbulence encounter at Sydney Airport.

Sydney Airport is the only major Australian airport currently with parallel runways. The distance between these runways is such that they are treated as individual runways and do not require the application of the wake turbulence separation standard for aircraft operating to a single runway.

The investigation found that at Sydney Airport, when the time between arriving aircraft (including those operating on parallel runways) is less than one per minute, the likelihood of encountering wake turbulence increased substantially, with Runway 34 Right (the shorter of the parallel runways) the most likely to be affected.

Despite the distance between the parallel runways at Sydney Airport exceeding the regulatory standard (for aircraft separation to treat the parallel runways the same as a single runway), evidence indicates that wake turbulence generated by aircraft arriving on one runway can affect aircraft arriving on the parallel runway, especially under certain wind conditions. Aircraft arriving on Runway 34 Left were found to be the most likely cause for more than half of the Runway 34 Right arrival wake turbulence occurrences. A leading Airbus A380 (a super heavy aircraft) probably generated more than one‑third of these occurrences.

The rate of reported wake turbulence occurrences by arriving aircraft following an Airbus A380 was more than double that of any other aircraft type arriving at Sydney. All A380 wake turbulence occurrences took place outside peak arrival periods (one or more aircraft arrivals per minute). Medium weight aircraft, such as a Bombardier DHC-8 or Boeing 737, were more likely to report an encounter with wake turbulence than larger aircraft. No light aircraft reported encountering wake turbulence at the airport.

There were no reported wake turbulence occurrences at Sydney Airport between 2012 and 2016 that occurred during a reported loss of separation (breach of the wake turbulence separation standard). In contrast to wake turbulence occurrences, the rate of other turbulence occurrences at Sydney Airport is consistent with other major Australian airports.

The investigation concluded that there was a disproportionate rate and level of consequence of reported wake turbulence occurrences for aircraft arriving at Sydney Airport compared to other major Australian airports in the years 2012 to 2016. Given the parallel runway configuration, wake turbulence occurrences at Sydney Airport were found to be associated with:

• arrival densities of one or more aircraft per minute (including parallel runway arrivals), especially on flights that arrived on Runway 34 Right
• wind direction from the west or north‑west for aircraft arriving on Runway 34 Right, especially when coinciding with a heavy or super heavy aircraft arriving on Runway 34 Left
• arrivals following an Airbus A380 compared to other aircraft.

More than half of the wake turbulence occurrences during arrival at Sydney Airport were associated with one or more of the above three factors. Removing all of these factors would halve the occurrence rate and make it more comparable to other major airports, however, the rate at Sydney Airport would likely still be higher than other major Australian airports. This suggests other factors beyond the scope of this investigation are also influencing wake turbulence at Sydney.

What's been done as a result

Airservices Australia will publish an Aeronautical Information Circular (AIC) aimed at operators who operate into Sydney Airport. The AIC will advise industry of the injuries associated with wake turbulence for Runway 34 Right as identified in the ATSB Report. The AIC will also recommend that cabin crew should be seated and secured in the earlier part of the approach.

However, the ATSB did not consider that the proposed safety action would adequately reduce the risk associated with the safety issue. As such, the ATSB has issued a safety recommendation that Airservices introduce measures to reduce the frequency of wake turbulence occurrence at Sydney Airport.

Airservices has since informed the ATSB that the following measures will also be implemented:

• provide wake turbulence caution to aircraft on approach to 34R that will operate within the wake turbulence distance of a Heavy or Super heavy aircraft making an approach to runway 34L
• increasing separation distances for arrivals from 4 NM to 5 NM on runways 16L/R and 34L/R
• applying the single-runway wake turbulence standard to the parallel runways when the leading aircraft is a super heavy like an A380 and the following aircraft is light (under 25,000 kg).

The ATSB agrees that these have the potential to reduce the wake turbulence risk but encourages Airservices to consider conducting their own quantitative analyses to explore other options that could further reduce the risk of wake turbulence for aircraft arriving into Sydney Airport.

Safety message

When departing or arriving at Sydney Airport, aircrews need be alert to the increased likelihood of encountering wake turbulence especially during periods of high movement density or during parallel runway operations, when operating on Runway 34 Right with wind coming from the west or north-west, and/or following an Airbus A380.

__________

1. Occurrences (accidents, serious incidents or incidents) are defined, as a minimum, as an event associated with the operation of an aircraft which affects or could affect the safety of operation (International Civil Aviation Organization, Annex 13, Aircraft accident and incident investigation), and meets the definition of a ‘Transport Safety Matter’ (Transport Safety Investigations Act 2003, Section 23).

As the accountable authority for the Australian Transport Safety Bureau (ATSB), I am pleased to present the ATSB’s 2018–19 Corporate Plan, which covers the period 2018–19 to 2021–22.

This Corporate Plan sets out the ATSB’s purpose – to improve transport safety – and its strategies for achieving that purpose. The Plan also sets out the ATSB’s key deliverables and associated performance criteria. It has been prepared consistent with paragraph 35(1)(b) of the Public Governance, Performance and Accountability Act 2013 and the relevant provisions of the Transport Safety Investigation Act 2003 (the TSI Act), which establishes the ATSB. It also incorporates the Minister for Infrastructure and Transport’s Statement of Expectations (SOE) as notified under Section 12AE of the TSI Act.

The TSI Act provides that the ATSB’s primary purpose is to improve the safety of aviation, rail and marine transport through accident investigation, data analysis and safety education. It must do so independently while cooperating with the other organisations that share responsibility for transport safety, including counterpart organisations in other countries. Successive governments have indicated that, in carrying out its role, the ATSB should give priority to the safety of the travelling public.

To accomplish its primary purpose, the ATSB must take into account the known and projected environmental challenges associated with continuing growth, emerging technologies and safety trends across the aviation, rail and marine transport sectors. In response, the ATSB is preparing a Vision Statement 2025 that will provide a roadmap for the ATSB into the future, driving safety action in a rapidly changing transport environment. I will release the Vision Statement during the current year.  

In my capacity as Chief Commissioner and Chief Executive Officer, I am fully committed to maintaining the ATSB’s reputation as a world leading safety investigation body. Consistent with this commitment, I will work collaboratively with the relevant authorities to ensure the ATSB is appropriately resourced to fulfil its legislative duties and positioned to meet the expectations of our stakeholders and the broader travelling public.

Greg Hood
Chief Commissioner
28 August 2018

As the accountable authority for the Australian Transport Safety Bureau (ATSB), I am pleased to present the ATSB’s 2017–18 Corporate Plan, which covers the period 2017–18 to 2020–21.

This Corporate Plan sets out the ATSB’s purpose – to improve transport safety – and its strategies for achieving that purpose. The Plan also sets out the ATSB’s key deliverables and associated performance criteria. It has been prepared consistent with paragraph 35(1)(b) of the Public Governance, Performance and Accountability Act 2013 and the relevant provisions of the Transport Safety Investigation Act 2003 (the TSI Act), which establishes the ATSB. It also covers the Minister for Infrastructure and Transport’s Statement of Expectations (SOE ) as notified under Section 12AE of the TSI Act.

The TSI Act provides that the ATSB’s primary purpose is to improve the safety of aviation, rail and marine transport through accident investigation, data analysis and safety education. It must do so independently while cooperating with the other organisations that share responsibility for transport safety, including counterpart organisations in other countries. Successive governments have indicated that, in carrying out its role, the ATSB should give priority to the safety of the travelling public.

To accomplish its primary purpose, the ATSB must take into account the known and projected environmental challenges associated with continuing growth, emerging technologies and safety trends across the aviation, rail and marine transport sectors. In response, the ATSB has implemented a significant reform agenda that will position the agency to evolve its capabilities to deliver core functions in a more efficient and effective manner. A key enabler to this reform agenda has been the Government’s recent budget measure that will assist the ATSB in maintaining a sustainable resource base.

Through its contemporary workforce planning strategies, the ATSB will strive to attract, develop and retain the best people, with the requisite skills, knowledge and experience to meet the current and emerging challenges in transport safety investigation.

In my capacity as Chief Commissioner and Chief Executive Officer, I am fully committed to maintaining the ATSB’s reputation as a world leading safety investigation body. Consistent with this commitment, I will work collaboratively with the relevant authorities to ensure the ATSB is appropriately resourced to fulfil its legislative duties and positioned to meet the expectations of our stakeholders and the broader travelling public.

 

Greg Hood
Chief Commissioner

30 August 2017

As the accountable authority for the Australian Transport Safety Bureau (ATSB), I am pleased to present the ATSB’s 2016–17 Corporate Plan, which covers the period 2016–17 to 2019–20.

This Corporate Plan sets out the ATSB’s purpose, its strategies for achieving that purpose and how the effect of the strategies and the attainment of the ATSB’s purpose will be measured. It has been prepared consistent with paragraph 35(1)(b) of the Public Governance, Performance and Accountability Act 2013. The Plan takes account of the relevant provisions of the Transport Safety Investigation Act 2003 (the TSI Act), which establishes the ATSB. It also has regard to the views of the Minister for Infrastructure and Transport on the ATSB’s strategic direction as notified under Section 12AE of the TSI Act.

The TSI Act provides that the ATSB’s primary purpose is to improve the safety of aviation, rail and marine transport through accident investigation, data analysis and safety education. It must do so independently, but in cooperation with the other organisations that share responsibility for transport safety, including counterpart organisations in other countries. Successive governments have indicated that, in carrying out its role, the ATSB should give priority to the safety of the travelling public.

To accomplish its primary objective, legislated key functions and broader portfolio responsibilities, the ATSB must take into account the financially constrained environment in which it operates. Since becoming an independent statutory authority in July 2009, the ATSB’s base appropriations have continued to reduce over successive financial years with further reductions projected over the forward estimates. Within this setting the ATSB must also remain vigilant of the opposing continued growth in, and progressive changes to, the composition of the aviation, rail and marine transport sectors.

In response, the ATSB will need to further enhance its data-driven approach to transport safety through increasing its capacity to carefully analyse available occurrence data. This will enable the ATSB to selectively allocate its limited resources towards investigating those accidents and incidents that will have the greatest potential for safety learnings and enhancement. It will also expand the ATSB’s capacity to identify emerging threats to transport safety.

The ATSB strives to maintain the people, information and systems to be a world leader in its field. This includes having the residual capability to manage an immediate and sustained response to a significant transport safety event, whether it be a major accident or, as is the current case, to undertake a major safety project such as the search for the missing Malaysia Airlines flight MH370. The ATSB’s ability to meet this overarching responsibility will remain subject to the limitations imposed by increasingly constrained resources and growing demands.

As the recently appointed Chief Commissioner, I am fully committed to maintaining the ATSB’s reputation as a world leading safety investigation body. Consistent with this commitment, I will work collaboratively with the relevant authorities to ensure the ATSB is appropriately resourced to fulfil its legislative duties and positioned to meet the expectations of our stakeholders and the broader travelling public.

Greg Hood
Chief Commissioner
31 August 2016

Introduction

As the accountable authority of the Australian Transport Safety Bureau (ATSB), I am pleased to present the

, which covers the period 2015–16 to 2018–19.

This Corporate Plan sets out the ATSB’s purpose, its strategies for achieving that purpose and how the effect of the strategies and the attainment of the ATSB’s purpose will be measured. It has been prepared in accordance with paragraph 35(1)(b) of the Public Governance, Performance and Accountability Act 2013. The Plan takes account of the relevant provisions of the Transport Safety Investigation Act 2003 (the TSI Act), which establishes the ATSB. It also has regard to the views of the Minister for Infrastructure and Regional Development on the ATSB’s strategic direction as notified under Section 12AE of the TSI Act.

The TSI Act provides that the ATSB’s primary purpose is to improve the safety of aviation, rail and marine transport through accident investigation, data analysis and safety education. It must do so independently, but in cooperation with the other organisations that share responsibility for transport safety, including counterpart organisations in other countries. Successive governments, including the current one, have indicated that, in carrying out its role, the ATSB should give priority to the safety of the travelling public.

The ATSB is required to maintain the people, information and systems to be a world leader in its field. This includes the standing capability to respond immediately to a significant transport safety event, whether it be a major accident or, as is the current case, to undertake a major safety project such as the search for the missing Malaysia Airlines flight MH370. This plan sets out its strategies for doing so in an environment of fast technological advances, constrained resources and significant demographic change in its workforce.

The ATSB has consistently proven itself to be at the forefront internationally in its capability and in its results. I look forward to continuing that achievement as the ATSB implements this Corporate Plan.

 

Martin Dolan
Chief Commissioner

31 August 2015

Why the ATSB did the research

Fatigue is an inevitable risk in aviation. As it cannot be completely eliminated, it must be managed. Data on fatigue and its impact on air transport safety is generally only obtained if there is an incident or accident. As a result, there is generally a lack of understanding of the baseline level of fatigue in day-to-day Australian air transport across operators.

To provide the air transport industry, regulators and policy makers with further insights into industry perceptions of fatigue, the ATSB conducted a survey of commercial pilots engaged in passenger, freight, and aeromedical operations in the second half of 2016. To understand the reported level of fatigue during normal operations, the survey aimed to discover the amount of sleep and rest obtained by pilots, as well as their perceptions on the length of rests and duty times. The survey also aimed to capture data on the organisational aspects of fatigue, including how pilots feel about removing themselves from duty because of fatigue experienced and how they think management perceive this behaviour.

What the ATSB found

The majority of survey respondents reported they were sufficiently well rested by the end of their last duty. Over half of pilots reported having 7 hours of sleep or more in the previous 24 hours, and over 60 per cent reported having more than 14 hours in the previous 48 hours, at the end of the last flight. The survey also found a small but significant number of pilots, 10 per cent and 17 per cent, who reported obtaining less than 5 hours of sleep in the previous 24 hours, or less than 12 hours in the previous 48 hours, respectively, at the end of their last flight. These sleep thresholds have been shown to be associated with impaired performance.

Less sleep on duty was more prevalent for international and domestic jet airline pilots than other air transport pilots (regional, charter and aeromedical). While around one third of the respondents reported obtaining the same amount of sleep at home as they did while on duty, around half of international and domestic pilots reported obtaining less hours of sleep on duty than at home. About 15 per cent of international pilots responded they had no rest during their last international flight.

Domestic pilots completed duties on a stand-by day more often than other pilots. Some believed the rest period between duties was too short, duty periods were too long, and access to food during duties was more difficult compared with other pilots, indicating some pilots within this group have negative perceptions of rest opportunities provided by their employers.

Over 90 per cent of pilots indicated their employer offered a formal process for removing themselves from duty due to fatigue. About one third of respondents indicated they removed themselves from duty at least once in the past year, mostly between one and three days. The pilots who removed themselves from duty generally perceived their actions left a negative impression with management (with the exception of aeromedical pilots) and did not feel comfortable doing so.

Safety message

Responsibility to manage the risk of fatigue lies with both the individual pilot and organisation. It is the individual pilot’s responsibility to use rest periods to obtain adequate sleep and to remove themselves from duty if they feel fatigued. It is important for operators to implement policies to reduce the likelihood of fatigue-related issues through rostering practices and by providing an organisational culture where crew can report fatigue in a supportive environment. The results of this research suggest that operating in circumstances conducive to fatigue is an ongoing challenge for a proportion of Australian air transport pilots.

The online report includes interactive functionality allowing users to access the report’s safety data to create their own reports specific to their needs.

The purpose of this report

Each year, thousands of safety occurrences involving Australian and foreign-registered aircraft are reported to the Australian Transport Safety Bureau (ATSB) by individuals and organisations in Australia’s aviation industry and by members of the public.

This report is part of a series that aims to provide information to the aviation industry, manufacturers and policy makers, as well as to the travelling and general public, about these aviation safety occurrences. In particular, what can be learned to improve transport safety in the aviation sector.

The study uses information over the ten-year period from 2008-2017 to provide an insight into the current and possible future trends in aviation safety.

What the ATSB found

The majority of air transport operations in Australia each year proceed without incident.

In 2017, nearly 200 aircraft were involved in accidents in Australia, with 203 involved in a serious incident (an incident with a high probability of an accident). There were 40 fatalities in the aviation sector in 2017, which was a significant increase from the 21 fatalities in 2016. There were no fatalities in either high or low-capacity regular public transport (RPT) operations, which has been the case since 1975 and 2010 respectively.

Almost half of all fatalities that occurred in commercial air transport operations during the study period occurred in 2017. During 2017, there were 14 fatalities from 21 accidents in commercial air transport operations, 21 fatalities from 93 accidents in general aviation operations, and five fatalities from 53 accidents in recreational aviation operations.

Terrain collisions were the most common accidents or serious incidents for aircraft involved in general aviation, recreational aviation and remotely piloted aircraft in 2017. Aircraft control, followed by terrain collisions, were the most common occurrence type associated with an accident or serious incident for aircraft involved in air transport operations.

Wildlife strikes, including birdstrikes, were again the most common type of incident involving both commercial air transport and general aviation operations. Runway events and aircraft control incidents were the most common types of incident reported for recreational aviation.

The accident and fatal accident rates for general and recreational aviation reflect their higher‑risk operational activity when compared to commercial air transport operations. They also reflect the significant growth in recreational aviation activity over the last ten years and this sector’s increased reporting culture.

General aviation accounts for one‑third of the total hours flown by Australian-registered aircraft and over half of all aircraft movements across Australia.

The total accident rate, per hours flown, indicates general aviation operations are nine times more likely to have an accident than commercial air transport operations, with recreational operations around twice as likely to experience an accident than general aviation operations.

The fatal accident rate, per hours flown, indicates general aviation operations are around fifteen times more likely to experience a fatal accident than commercial air transport operations, and recreational operations are almost 30 times more likely to experience a fatal accident than commercial air transport operations.

Private/business helicopters followed closely by recreational gyrocopters had the highest fatal accident rate for any aircraft or operation type, whereas recreational aeroplanes had the highest total accident rate. There were no fatal accidents involving general aviation balloons reported during the study period.

Aeroplanes remain the most common aircraft type flown, which is reflected in the proportion of accidents they are involved in. In 2017, 15 of the 22 fatal accidents involved aeroplanes—three gliders, two helicopters, and two weight shift aircraft were also involved in fatal accidents.

Since 2016, the increased availability and use of remotely piloted aircraft (RPA) saw them match helicopters as the second highest aircraft type for reported accidents. However, there were no collisions with other aircraft, fatalities or serious injuries relating to RPA reported to the ATSB. While the consequences of an accident involving an RPA have been low to date, their increased use, and possible interactions with traditional aviation, is an emerging trend in transport safety that will continue to be monitored closely by the ATSB.

Note: Previous editions of Aviation Occurrence Statistics reports contained an error regarding the number of occurrences and subsequently rates for balloons conducting general aviation operations and air transport - charter operations. This error was communicated to the ATSB by the Australian Ballooning Federation. A systemic error was identified and rectified within the reporting system. This report has a decrease in the number of occurrences, and rates, for balloons conducting private operations, and a corresponding increase for balloons conducting charter operations compared to previous editions.

Safety message

This report highlights the importance of effective and timely reporting of all aviation safety occurrences, not just for the potential of initiating an investigation, but also for further study and analysis of aviation transport safety.

While there has been an increase in accident and incident reporting, the limited detail provided for most occurrences, especially by recreational flyers, remains a challenge for the industry and ATSB. This report also highlights the need for improvements in the reporting rates for some areas in general aviation.

By comparing accident and occurrence data across aviation operation types, the ATSB is able to develop a complete picture of the aviation industry to identify emerging trends in aviation transport safety, identify further areas for research and recommend pre-emptive safety actions.