Safety summary

What happened

On 15 February 2013, the crew of a Eurocopter Helicopter MBB‑BK117 B-2 (BK117), registered VH-VSA, were conducting a trauma recovery flight from Port Pirie to Adelaide Hospital, South Australia. After reaching the cruise altitude of 5,000 ft above mean sea level, the crew observed fluctuations of the hydraulic system pressure gauges. Shortly after, the helicopter sustained an uncommanded and violent nose-up pitch and rolled left before descending. The pilot regained control at about 800 ft above ground level. Control checks by the pilot confirmed normal control had resumed and the pilot flew the helicopter back to Port Pirie Aerodrome. No injuries were reported by the occupants and the helicopter sustained minor damage.

What the ATSB found

The ATSB did not find any mechanical or system faults that could account for the hydraulic system pressure fluctuations. The ATSB found that the helicopter was being operated at a weight, density altitude and airspeed, and in meteorological conditions that were conducive to the onset of retreating blade stall. The uncommanded and violent nose-up pitch and left roll were consistent with the onset of that condition. The pilot’s instinctive action of pushing the cyclic control forward delayed recovery from the stall.

What's been done as a result

The operator issued an urgent Immediate Safety Notification advising all company BK117 pilots of the conditions conducive to retreating blade stall and the correct actions to recover from that condition.

Safety message

This incident highlights the importance of pilot awareness of the factors conducive to retreating blade stall, including high all-up weight, high density altitude, high airspeed, manoeuvres that increase flight loads and flight in turbulence. Similarly, the importance of initially reducing collective pitch to optimise recovery is emphasised as incorrect recovery actions can result in loss of control of the helicopter.

Safety summary

What happened

On 12 February 2013, intermodal freight train 3MC1 derailed at Locksley, near Seymour in Victoria. The train consisted of two locomotives (GL107 leading and GL101 trailing) hauling 33 wagons having a trailing mass of 921.1 t and an overall train length of 885.5 m. There were no injuries but the last eight wagons derailed and about 800 m of track was damaged.

What the ATSB found

The ATSB determined that the derailment of freight train 3MC1 at Locksley was most likely the result of a track misalignment at the 127.768 km mark on the West Line of the interstate mainline. Hot weather in the period preceding the derailment, and trains travelling along the track, probably caused a redistribution of longitudinal rail stresses in a northerly direction towards the derailment site. The track structure near the derailment site probably had a reduced capacity to withstand lateral forces, due to track quality (ballast contamination). This, coupled with maintenance activities close to the derailment site, most likely initiated a redistribution of longitudinal forces towards the 127.768 km mark and increased the likelihood of a track buckling event.

What's been done as a result

Australian Rail Track Corporation track maintenance staff have been provided with additional training on the consequences of multiple track disturbances altering the stress free temperature of rail track. The training will provide an enhanced level of compliance with the requirements of procedure ETM-06-06 (Managing Track Stability - Concrete Sleepered Track).

Following the derailment and subsequent reinstatement of the track the Australian Rail Track Corporation undertook stress free temperature testing at ten sites near the ‘Point of Derailment’. Tests established that the rail stress free temperature was within specified tolerances.

The Australian Rail Track Corporation has implemented a ballast remediation program on the Melbourne – Sydney rail corridor. This work will continue as programmed until completed, following which further works will be undertaken at sites having identified formation weakness.

Safety message

Track managers must consider the potential impact of track disturbing maintenance activities on lateral track stability, particularly in areas having poor ballast quality and during periods when temperatures are significantly higher than the rail neutral temperature.

What happened

On 9 February 2013, a Cessna 150F, registered VH-ICE (ICE), landed on the 11^th fairway of the Mt Broughton Golf Club, New South Wales after the initial leg of a return flight from Robertson. The pilot was the only person on-board and had been authorised and pre-arranged with the Golf Club to use the fairway as a landing area.

After landing to the south, the pilot backtracked along the landing area to conduct a short field take-off in the same direction.

The pilot reported that the aircraft accelerated as normal, however during the take-off run he realised the aircraft would not clear the trees at the end of the landing area and elected to reject the take-off. The left wing impacted a tree; the aircraft turned over and came to rest inverted. The pilot was uninjured, and the aircraft sustained substantial damage.

An insurance assessor attended the accident site and reviewed the landing area. The assessor determined that the effective available take-off length of the landing area was 1,180 ft. Based on performance charts in the approved Cessna 150F owner’s manual, the take-off distance required by the unmodified Cessna 150 F was 1,583 ft. There was no available performance data that took into account the installation of the 160 hp engine.

This accident highlights the importance of following the published performance data for your aircraft and knowing the performance requirements, physical characteristics and dimensions of the landing area that you are intending to take-off and land on. Other factors, such as environmental conditions, may affect the usable landing area length needed for a safe take off, landing or rejected take-off.

Aviation Short Investigation Bulletin Issue 19

What happened

On 7 February 2013 at about 1655 Eastern Daylight-saving Time a Eurocopter AS350 B2 helicopter, registered VH-EWM (EWM) was conducting water-bombing operations near Hobart, Tasmania, when it collided with terrain. The pilot, the sole person on board, suffered minor injuries and the helicopter sustained substantial damage.

The spot fire EWM was working on was not particularly large but was on a downhill slope and in a gully. The pilot reported that the overall wind was north-north-westerly, but the fire created a localised westerly in-draft, within the gully. The pilot slowed EWM in preparation of making a water drop. Approaching the hover at about 80 ft above ground level, and immediately following the loss of translational lift (TL), the helicopter suddenly commenced an uncommanded left yaw and descent. Without any warnings or alarms, the helicopter rotated rapidly 2-3 times to the left. The pilot raised the collective to decrease the rate of descent and countered the yaw with anti-torque pedal input; however, the rate of yaw increased. The pilot reported that “in a very short period of time” the helicopter was in the trees. The pilot received minor injuries, and the helicopter was substantially damaged.

As the ATSB did not attend the accident site, or examine the helicopter, the reason for the accident could not be conclusively established.  The described behaviour of the helicopter by the pilot was consistent with Loss of tail rotor Effectiveness (LTE). In this condition of flight, the tail rotor loses aerodynamic efficiency. Factors which contribute are:

• Low airspeed
• High power
• An adverse relative wind

Water-bombing helicopters operate at very low altitudes, in very challenging and often rapidly changing conditions. Any sudden onset of an abnormal condition of flight presents negligible time for recovery.

Eurocopter circulated Service Letter No 1673-67-04 in 2005 regarding the yaw axis control features for all helicopters under certain flight conditions.

Aviation Short Investigation Bulletin Issue 20

What happened

On 5 December 2012, containerised grain train 8448N, travelling from Gilgandra to Walsh Island (Newcastle) was undergoing a roll-by examination at Gulgong, NSW, when inspectors noted a significant structural failure within the number-20 wagon of the consist. The wagon (SQDY 00060-G) had fractured transversely through the central box section main longitudinal member.

The NSW Office of Transport Safety Investigations (OTSI) was responsible for investigating this occurrence. To facilitate the examination of the technical and metallurgical aspects of the failure, OTSI requested assistance from specialist staff at the Australian Transport Safety Bureau (ATSB). To facilitate that assistance and afford the necessary protections to any sensitive information obtained during the course of the work, the ATSB initiated an External Investigation under the provisions of the Transport Safety Investigation Act 2003.

On 16 January 2013, an ATSB specialist examined the failed wagon (and a second wagon that had presented cracking) alongside representatives from OTSI, the NSW Rail Safety Regulator and the wagon maintenance provider. Subsequently and throughout the investigation, the ATSB provided advice and commentary; including a review of the draft investigation reports and a failure investigation report commissioned by the operator.

The NSW Office of Transport Safety Investigations is responsible for releasing a final investigation report into this occurrence – all inquiries regarding the investigation or the report release should be forwarded to the OTSI.

• NSW Office of Transport Safety Investigations website

Safety summary

What happened

At about 1440 Eastern Daylight-saving Time on 22 January 2013, the pilot of a Cessna U206F amphibious aircraft, registered VH-UBI, was conducting a seaplane joy flight from Corio Bay, Victoria with two passengers on board. During the flight the pilot refuelled the aircraft at Barwon Heads Airport, necessitating the use of the landing wheels. On the return trip the pilot detoured for local sightseeing before heading back to Corio Bay for a water landing. On touchdown, the aircraft pitched over and came to rest inverted. The pilot assisted the two passengers to evacuate the aircraft before rescue vessels arrived. All three occupants sustained minor injuries. The aircraft was substantially damaged.

What the ATSB found

The ATSB found that the pilot was distracted during the departure from Barwon Heads and as a result did not retract the landing wheels during the after-take-off checks. The investigation also determined that on returning to Corio Bay, the pilot shortened the approach due to perceived time pressure and did not complete the normal downwind and short final checks. In not completing those checks, the pilot reduced the likelihood of identifying that the landing wheels were still extended. Such events where individuals forget to carry out an action due to distractions are not uncommon and are described as skill-based lapses.

Safety message

This accident is a reminder for pilots and operators that human error can occur at any time, and highlights the importance of managing operational pressures and avoiding distractions. The need to follow procedures and complete checklists diligently is also reinforced. Effective application of threat and error, and distraction management principles can reduce risk.

The operator’s requirement for passengers to wear life jackets throughout the flight enhanced the survivability of the passengers.

Safety summary

What happened

At about 0940 on 31 January 2013, a Queensland Rail passenger train (T842) failed to stop at the Cleveland station platform and collided with the end-of-line buffer stop, the platform and the station building at a speed of about 31 km/h. There were 19 people on board the train (including the driver and a guard); three people were on the platform and five were in the station building. A number of people were treated for minor injuries and transported to hospital for further examination.

At the request of the Queensland Government, the ATSB initiated an investigation into the accident.

What the ATSB found

The ATSB’s investigation found that local environmental conditions had resulted in the formation of a contaminant substance on the rail running surface. This caused poor adhesion at the contact point between the train’s wheels and the rail head. The braking effectiveness of train T842 was reduced as a result of reduced adhesion and the train was unable to stop before hitting the end-of-line buffer stop.

The ATSB concluded that Queensland Rail’s risk management processes prior to the accident had not adequately assessed, recorded, managed and communicated the risks associated with operating trains on their network under low adhesion conditions.

In addition, Queensland Rail had not undertaken exercises to test the preparedness and effectiveness of their emergency management system. Shortfalls were identified in the response to the accident with respect to internal communications within train control and between staff at Cleveland station which resulted in incomplete information being provided to key personnel.

What's been done as a result

Queensland Rail initiated a risk mitigation strategy in response to the collision of train T842 at Cleveland station on 31 January 2013. The strategy included the formation of a Wheel Rail Interface Working Group that identified the wheel/rail interface risks, particularly for Queensland Rail’s fleet of IMU160/SMU260 class trains being operated under certain conditions.

Queensland Rail have also implemented a series of risk controls including identifying localised black spot locations and applying vegetation control measures, treating rail-head contaminants, reviewing and updating driver training with enhanced train handling advice about wheel slide and the trialling of sanding equipment on IMU160/SMU260 class trains. Queensland Rail have now undertaken emergency exercises to test the effectiveness of their emergency response arrangements and are implementing new communication protocols for emergency incident response.

Safety message

Rail operators should recognise that train braking performance may be significantly impaired when local environmental conditions result in contaminated rail running surfaces and reduced wheel/rail adhesion. Rail operators should put appropriate measures in place to assess and mitigate the risk to the safe operation of trains under these conditions.

What happened

On the evening of 28 January 2013, VH‑YFF was being prepared for a scheduled passenger service from Canberra, Australian Capital Territory to the Gold Coast, Queensland. The crew were aware of adverse weather conditions being experienced at the time in south-east Queensland and had been monitoring the weather at the Gold Coast throughout the day.

During the approach, the crew reported that they were in cloud and experiencing rain and a strong right crosswind of about 40-50 kt. The Tower controller advised the crew that the crosswind on the ground was 21 kt. The captain reported that he was mindful of the wind conditions and was prepared to initiate a go-around.

At about 1,000 ft above mean sea level (AMSL), the crew became visual with the runway.

At about 100 ft, the captain noted that the airspeed trend vector was indicating a 20 kt decrease, likely the result of undershoot windshear. The captain momentarily increased engine thrust.

At about 2229, the aircraft touched down about 200 m further along the runway than intended. The first officer (FO) recalled the aircraft touched down on, or slightly right of the runway centreline. At that time, they were experiencing light rain.

After touchdown, the captain perceived that the aircraft was close to the left side of the runway, due to the proximity of the runway edge lights. The captain immediately applied right rudder, however, he inadvertently overcorrected, resulting in the aircraft veering to the right side of the runway. The captain applied left rudder, and the runway centreline was regained. The aircraft was slowed to taxi speed and taxied to the terminal.

Due to the weather conditions and high workload at the time, the captain was not certain if the aircraft was pointing towards the runway edge before touchdown or if the aircraft aquaplaned after touchdown. The FO reported that it felt like the aircraft aquaplaned and drifted to the left.  However, after reviewing the flight data, the captain believed that the aircraft flared on centreline and drifted left before touchdown.

Through its SafetyWatch initiative, the ATSB is highlighting an increasing trend in problems with aircraft handling and flight profile when unexpected events arise during the approach to land. When compared to other phases of flight, the approach and landing has a substantially increased workload. Further details are available at www.atsb.gov.au/safetywatch/handling-approach-to-land.aspx

Aviation Short Investigation Bulletin  - Issue 23

Safety summary

What happened

On 30 January 2013, Pacific National freight train 9837, travelling from Nowra to Orange, passed signals SM109G and SM115G at stop on the Down Goods line between Dulwich Hill and Hurlstone Park in Sydney. Just prior to this incident a work crew had been working on the track under the protection of Absolute Signal Blocking (ASB). There were no injuries or damage.

What the ATSB found

The ATSB’s investigation found that the train crew did not take action in response to the indications of three consecutive signals, resulting in the passing of two of those signals at stop without authority (also called a SPAD). It was found that the more senior co-driver had inadvertently fallen asleep on the approach to these signals. The trainee driver, in a reduced state of alertness, missed the first signal at caution, and the next signal at stop. He applied the brakes once the train passed the final signal at stop after realising this signal applied to his train.

Two persons from a litter pickup work crew were on the track just before the train passed through their worksite. Once alerted to the train’s approach they moved off the tracks and to a safe place behind the platform at Hurlstone Park station.

A number of Pacific National’s policies and procedures were examined to determine if any area of the management or training of the train crew contributed to the incident. Fatigue management, and in particular over- reliance on the use of bio-mathematical model scores used to roster train crew, was one area where improvement was needed. The ATSB also found that there was an absence of adequate procedures and training for drivers who were performing co-driving duties while coaching trainee drivers.

What's been done as a result

As a result of the incident Pacific National has undertaken a range of actions to improve its approach to fatigue management and the implementation of fatigue training. They have also commenced a review of SPAD risk management processes and training requirements for coach/tutor drivers. A trial has commenced of improved data loggers for the Bulk Rail fleet.

Safety message

In order to minimise fatigue-related errors, rail operators should ensure that fatigue management systems incorporate integrated and multi-layered risk control mechanisms. Rail operators should also recognise that the training of drivers by advanced drivers during operations increases exposure to workload and other risks that need to be managed. In addition, SPAD strategies devised by rail operators should have regard to broad systemic issues rather than focus simply on individual train crew actions.

What happened

On 29 November 2012, the ATSB commenced an investigation into a loss of separation involving two Qantas Airways Airbus A330s, registered VH-EBM (flying as QFA485) and VH-QPC (flying as QFA762). The loss of separation took place approximately 148 km east of Narrogin, Western Australia, on 28 November 2012 with the aircraft on crossing tracks.

VH-EBM was inbound to Perth maintaining flight level (FL) 380[1] and VH-QPC was outbound from Perth on climb to FL 410. A short-term conflict alert was received by the controller as VH-QPC climbed through FL 370, approximately 15 NM (about 28 km) before the aircraft passed.

In response, the controller initiated compromised separation recovery actions. During this recovery action, separation between the two aircraft reduced to 2.84 NM (5.26 km) laterally and 900 ft vertically. There were no traffic collision avoidance system[2] alerts.

In reviewing the information gathered during its investigation, the ATSB determined that there were no associated safety issues or elements of the occurrence that have not already been covered in detail in other recent air traffic-related investigations (see AO-2011-090, AO-2012-012 and AR‑2012‑034).[3] The controller in question had completed compromised separation recovery training and had 8 months consolidation on this sector following their initial rating and en route endorsement. There were no identified training, rostering, fatigue or staffing issues and sector handover/takeover was not a factor. While the controller involved had been under moderate to high workload earlier in the shift, the workload was low at the time of the occurrence and there was no evidence that distraction was a factor.

The controller was responsible for two airspace sectors at the time of the occurrence. Airservices Australia has since undertaken significant work in re-structuring the sectors in the airspace over Western Australia. Although the ATSB determined that required voice coordination between sectors was not completed by the controller in this occurrence, this did not affect the controller’s awareness of the traffic as he was already interacting with the aircraft that were involved in the occurrence.

The ATSB did not find any organisational or systemic issues that contributed to the occurrence or that might adversely affect the future safety of aviation operations. On that basis, the ATSB has decided to discontinue its investigation.

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