What happened

On 27 June 2020, the owner of a Cessna 210H was conducting a private local flight at Hamilton, Victoria. The pilot was the only occupant on board.

As the aircraft re-entered the circuit and the pilot lowered the undercarriage, an unfamiliar noise was detected emanating from underneath the aircraft. The pilot checked the wing mirror to ensure the landing gear was down and observed the main right wheel was partially extended and not in a locked position. The pilot conducted operational checks on the landing gear and attempted to manually lock the undercarriage, however all attempts were unsuccessful.

The pilot notified Melbourne air traffic control of the situation and broadcast to local aircraft on the CTAF. The aircraft entered a hold over Hamilton to ensure emergency services had time to arrive at the airport. The pilot then notified nearby aircraft of the intention to land and conducted a wheels-up landing on the grassed area parallel to the runway, resulting in minor damage to the lower fuselage and propeller.

Safety message

This incident highlights the effectiveness of sound decision-making when presented with minimal options in emergency situations. In this instance, the pilot identified the fault, conducted trouble-shooting and provided clear communication about the intention to conduct a wheels-up landing. CASA has released a Decision Making booklet, which provides further advice on how to make sound decisions in high workload environments.  

About this report

Decisions regarding whether to conduct an investigation, and the scope of an investigation, are based on many factors, including the level of safety benefit likely to be obtained from an investigation. For this occurrence, no investigation has been conducted and the ATSB did not verify the accuracy of the information. A brief description has been written using information supplied in the notification and any follow-up information in order to produce a short summary report, and allow for greater industry awareness of potential safety issues and possible safety actions.

What happened

On 17 June 2020, the pilot of a Cessna 310 commenced the first flight of the day from runway 11 at Darwin, Northern Territory. This was a planned charter flight with one pilot and four passengers on board. As the aircraft accelerated down the runway, the pilot observed an indicated airspeed of 40 kt, and with the understanding the airspeed was live,^[1] attention was turned to engine readings and maintaining directional control for the remainder of the take-off run.

Shortly after becoming airborne, the pilot checked the airspeed and noticed that the indicated airspeed was now zero. A rejected take-off was not possible with the height already achieved and the length of runway remaining, so the pilot contacted air traffic control and conducted a return to land.

Upon exiting the aircraft, the pilot discovered the cover had been left on the pitot tube^[2] (Figure 1). The operator assessed that the indication early in the take-off was likely due to fluctuations in pressure as the aircraft accelerated. The pitot cover was removed and the flight proceeded without further incident.

Operator comment

The aircraft operator has advised the ATSB that they have conducted a debrief with the pilot that included the pilot’s obligation to conduct a final walk-around prior to engine start.

Figure 1: Pitot tube cover

Source: Operator.

Figure 2: Cessna 310 pitot tube location

Source: Stock photo; inset photo provided by operator. Annotated by the ATSB.

Safety message

This incident highlights the importance of ensuring that all pre-flight checks and procedures are carried out systematically as detailed in the flight manual.

It also serves as a reminder to remain vigilant with monitoring and checking aircraft performance, in particular during the critical phases of flight. Indicated airspeed is the primary means of determining whether an aircraft will have sufficient performance available to climb away, or if the pilot’s best course of action is to reject the take-off.

About this report

Decisions regarding whether to conduct an investigation, and the scope of an investigation, are based on many factors, including the level of safety benefit likely to be obtained from an investigation. For this occurrence, no investigation has been conducted and the ATSB did not verify the accuracy of the information. A brief description has been written using information supplied in the notification and any follow-up information in order to produce a short summary report, and allow for greater industry awareness of potential safety issues and possible safety actions.

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1. Live: a term used to indicate that the needle or speed tape on the airspeed indicator is moving and indicating an airspeed above its minimum value.
2. Pitot tube: an open-ended tube that forms part of the pitot-static system used to measure airspeed and altimetry.

What happened

On 30 June 2020 at 1055 Western Standard Time, a Cessna 402 departed Groote Eylandt Airport for a charter flight to Darwin, Northern Territory (NT). There were two crew and five passengers on board.

During cruise at 10,000 ft, the aircraft experienced a rough running engine. The pilot began to troubleshoot the issue and observed the oil pressure dropping to zero. A short time later, the no. 1 engine sustained a total power loss.

The pilot completed the emergency checklists for the engine failure, contacted Brisbane Centre air traffic control and declared a PAN PAN.^[1] The aircraft was diverted to Jabiru Aerodrome, NT and emergency services were organised for the arrival. The pilot then notified the passengers of the incident and planned diversion.

Prior to joining the circuit at Jabiru, the pilot reviewed the one engine inoperative checklist and planned the approach for runway 09. The aircraft landed without further incident.

Engineering inspection

The engineering inspection revealed the engine’s no. 5 cylinder piston had failed due to detonation. When the contaminates from the piston entered the crankcase^[2] and the sump, engineers suspect that the volume of the contaminates blocked the oil pick up scavenge screen and the pump ran dry. This was evidenced by lack of oil in the oil filter canister.

The no. 1 and no. 2 connecting rod big end bearings on the crank journal ran dry and once the bearings started to break down, the extreme heat and pressure stretched the no. 2 connecting rod bolts which then failed. Both connecting rods failed and contacted the top of the crankcase, leaving a hole in the case and breaking off the left magneto.

Safety message

This incident highlights the importance of flight crews maintaining awareness of all system states and being prepared to act as early as possible. In this incident, the pilot was quick to identify and troubleshoot the engine failure and followed procedures to ensure a safe outcome.

About this report

Decisions regarding whether to conduct an investigation, and the scope of an investigation, are based on many factors, including the level of safety benefit likely to be obtained from an investigation. For this occurrence, no investigation has been conducted and the ATSB did not verify the accuracy of the information. A brief description has been written using information supplied in the notification and any follow-up information in order to produce a short summary report, and allow for greater industry awareness of potential safety issues and possible safety actions.
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1. PAN PAN: An internationally recognised radio call announcing an urgency condition which concerns the safety of an aircraft or its occupants but where the flight crew does not require immediate assistance.
2. Crankcase: A crankcase is the housing for the crankshaft in a reciprocating internal combustion engine. The crankcase provides an enclosed volume for the crankshaft motion and piston connecting rods to move and operate.

What happened

On 4 June 2020, a Cessna 210M departed Darwin for a charter flight to Maningrida, Northern Territory. There was a pilot and three passengers on board.

After take-off, the aircraft was cleared to climb to 7,500 ft and track direct to Maningrida. During cruise, the pilot switched from the left to the right fuel tank. Approximately 26 minutes after the tank switch, the pilot observed the exhaust gas temperature rising and the fuel flow gauge fluctuating. The pilot then turned on the fuel pump and observed that the fuel flow gauge ceased to fluctuate. Once the fuel pump was turned off again, the fuel flow fluctuations increased in severity, the engine’s performance was diminished and the RPM dropped. The engine subsequently stopped.

The pilot immediately turned on the fuel pump, reduced the mixture lever to halfway, switched the fuel tank from right back to left and successfully restarted the engine. With no suitable landing areas identified, the pilot closely monitored the engine’s performance and maintained 6,000 ft until overhead Maningrida. The aircraft joined the circuit and landed without further incident.

Post-flight, the pilot checked that the fuel caps were secured correctly and conducted a fuel drain to check for contamination, of which there was none.

Engineers conducted a thorough inspection of the fuel system and discovered mud wasp nests in both fuel vent lines.

Safety action

As a result of this incident, the operator and maintenance organisation advised the ATSB that they have taken the following safety action:

• A full fleet inspection was conducted where all fuel vent lines were examined for blockages.
• Fuel cap venting will be checked during 100 hourly aircraft inspections.

Safety message

The ATSB has investigated a number of incidents involving insect activity disrupting aircraft systems and causing blockages that have been particularly difficult to identify.  Mud wasps in particular, can build nests in aircraft that are stationary for very short periods of time. This incident serves as a reminder to operators that extra caution should always be taken in locations where known environmental hazards exist.

About this report

Decisions regarding whether to conduct an investigation, and the scope of an investigation, are based on many factors, including the level of safety benefit likely to be obtained from an investigation. For this occurrence, no investigation has been conducted and the ATSB did not verify the accuracy of the information. A brief description has been written using information supplied in the notification and any follow-up information in order to produce a short summary report, and allow for greater industry awareness of potential safety issues and possible safety actions.

What happened

On 23 April 2020, the pilot of a Diamond DA 40 was conducting a solo navigation flight from Gold Coast, Queensland to Brisbane West Wellcamp (Wellcamp), Queensland. On the same day, the pilot of a Cessna 172 was conducting a return solo navigation flight from Gold Coast and had planned to conduct circuit training at Wellcamp on the return leg.

The standard circuit altitude at Wellcamp is 2,500 ft for piston aircraft utilising a non-standard right-hand circuit for runway 12 to avoid high terrain to the north-east of the runway. At about 1430 Eastern Standard Time, the pilot of the DA 40 overflew active runway 12 at Wellcamp at 3,500 ft with the intention of descending on the dead side^[1] to join a right circuit. Around this time, the 172 was approaching the aerodrome from the west. Both pilots reported broadcasting on the common traffic advisory frequency (CTAF).

The pilot of the DA 40 conducted two descending orbits to join at the correct circuit height and as the aircraft turned back towards the runway to join midfield, the pilot detected the 172 on a converging track (Figure 1) and manoeuvred the aircraft to increase separation.

The two aircraft passed within close proximity, resulting in a vertical separation of approximately 100 ft and a horizontal separation of 300 m.

Figure 1: Relative flight paths and position of detected conflict (Diamond DA40 represented by green line, Cessna 172 represented by red line)

Source: Google Earth. Annotated by the ATSB

The 172 pilot had made an inbound call at 10 NM stating that they were, ‘on descent to 2,500 for midfield crosswind for left base runway 12.’ The pilot reported being aware of the requirement to conduct right-hand circuits for runway 12 but recalled hearing traffic already in the circuit area conducting left circuits and elected to follow the existing traffic. A descent to circuit height was conducted on the dead side for a left circuit; however, this resulted in the aircraft tracking in the opposite direction to circuit traffic at the same height. After the 172 pilot observed the DA 40 pass in close proximity, a CTAF call was made to query the runway direction, which was relayed as the published right-hand circuit. The 172 pilot elected to discontinue the approach to Wellcamp and climbed away on the dead side of the circuit before continuing on the navigation exercise.

Operator comments

The operator of the 172 has advised the ATSB that during their internal investigation, it was apparent that there was some confusion as to what direction circuits were actually being conducted prior to the arrival at Wellcamp. Although the query regarding circuit direction was made late by the pilot, this action avoided any further conflict.

Safety message

This incident highlights the need for pilots to consult the En Route Supplement Australia (ERSA) when flying to an unfamiliar aerodrome. As illustrated by this incident, not all non-controlled aerodromes follow the same procedures. Being aware of local traffic procedures helps pilots to anticipate the likely position of other aircraft.

Additionally, this incident reinforces the need for pilots to maintain situational awareness and a vigilant lookout at all times. This is especially important when operating at non-controlled aerodromes where pilots are responsible for monitoring and broadcasting their intentions on the CTAF as effective communication is vital to the prevention of potential conflicts developing. Research conducted by the ATSB has found that insufficient communication between pilots contributes to a breakdown of situational awareness. Further information about operating safely at non-controlled aerodromes can be found on the ATSB website, A pilot's guide to staying safe in the vicinity of non-controlled aerodromes and the CASA website, Radio procedures in non-controlled airspace.

The ATSB SafetyWatch highlights the broad safety concerns that come out of our investigation findings and from the occurrence data reported to us by industry. One of the priorities is Non-controlled airspace.

About this report

Decisions regarding whether to conduct an investigation, and the scope of an investigation, are based on many factors, including the level of safety benefit likely to be obtained from an investigation. For this occurrence, no investigation has been conducted and the ATSB did not verify the accuracy of the information. A brief description has been written using information supplied in the notification and any follow-up information in order to produce a short summary report, and allow for greater industry awareness of potential safety issues and possible safety actions.

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1. Dead side: The area on the opposite side of the runway to where the circuit is flown.

What happened

On 22 April 2020, a Cessna 182P departed Caloundra, Queensland (Qld), for a private flight to Bowen, Qld. The pilot was the only occupant on board.

During take-off, there was a strong burning smell present in the cabin. After completing the take-off checklist, the pilot checked the cabin heat, mixture levers and fuel selectors but was unable to identify the source of the fumes.

Passing 3,000 ft on climb, the smell dissipated. The pilot continued the climb and the aircraft levelled off at 8,500 ft. At this time, the pilot reduced power to cruising power and leaned out the mixture. Approximately 37 km south of Gympie, Qld, the engine began spluttering.

The pilot conducted further checks and increased the fuel mixture to full rich, but was unable to rectify the issue. Approximately 19 km south of Gympie, the engine spluttering became progressively worse and a drop in airspeed was observed. The pilot contacted air traffic control (ATC) to advise of the engine problem, declared a PAN PAN,^[1] and reported that the aircraft would be diverting to Gympie.

Following a safe landing at Gympie, the pilot conducted a visual inspection of the engine and performed a fuel drain and oil check. There was no visible damage to the engine and the fuel and oil levels and quantity were normal.

Pilot comments

The pilot reported that the aircraft had not been operated for an extended period prior to this flight and it is suspected that this is what contributed to both the fumes and the rough running engine.

Safety message

Faced with an abnormal situation, pilots are reminded that making an early decision to reject the take-off if it is safe to do so, or to conduct a precautionary landing as soon as practical will reduce the likelihood of further incident.

About this report

Decisions regarding whether to conduct an investigation, and the scope of an investigation, are based on many factors, including the level of safety benefit likely to be obtained from an investigation. For this occurrence, no investigation has been conducted and the ATSB did not verify the accuracy of the information. A brief description has been written using information supplied in the notification and any follow-up information in order to produce a short summary report, and allow for greater industry awareness of potential safety issues and possible safety actions.

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1. PAN PAN: an internationally recognised radio call announcing an urgency condition which concerns the safety of an aircraft or its occupants but where the flight crew does not require immediate assistance.

What happened

On 14 June 2020 at approximately 1600 Central Standard Time, the pilot of a Robinson R22 helicopter was conducting mustering operations on a property near Tindal Airport, Northern Territory.

The pilot was attempting to herd a number of cattle into a yard, which was proving difficult as the cattle were not moving as required. The pilot decided to land the helicopter behind the cattle to encourage them to move forward, and selected a landing site on a graded road bordered on either side by trees. The pilot was confident that the dust would be minimal in the selected landing area and planned to use a direct-to-the-ground approach to reduce the potential of creating a dust cloud and a possible brownout condition.^[1]

As the helicopter descended below 3 ft, an excessive amount of dust was raised from the landing area and the helicopter immediately became fully enveloped by the dust cloud. The pilot elected to reject the landing and commenced a climb, but as all visual references were lost and there were obstacles close by, the pilot quickly decided to put the helicopter on the ground as soon as possible.

The pilot lowered the collective^[2] and the helicopter contacted the ground with an amount of left lateral movement resulting in a rollover. The helicopter came to rest on its side sustaining substantial damage (Figure 1). The pilot was uninjured in the accident.

Figure 1: Helicopter post-accident

Source: Operator

Pilot comments

The pilot commented that normally a request for ground personnel assistance to herd the cattle would have been made, however as one of the ground personnel was recently injured the pilot was reluctant to ask for help. The pilot also advised that the mustering job had been delayed to late in the day, and therefore self-induced time pressure to complete the task existed. On reflection, the pilot advised the ATSB that these considerations may have influenced the decisions made on the day.

Brownout condition

The brownout phenomenon can lead to accidents during helicopter take-off and landing operations in arid / desert terrain. Dust clouds created by the rotor downwash during near-ground flight can result in the pilot losing visual reference. This increases the risk of the helicopter colliding with the ground and other obstacles, as well as dynamic rollover due to sloped, uneven terrain or uncommanded aircraft movement due to spatial disorientation.

There are several factors that affect the probability and severity of brownout:

• aircraft weight / rotor disk loading
• soil composition
• wind
• approach speed and angle.

Safety message

This accident highlights the importance of selecting a suitable landing area and the best approach path and landing technique for the surrounding environment. This includes consideration of appropriate escape routes when faced with an unexpected situation such as a brownout condition. Pilots should also always maintain situational awareness of environmental factors like wind direction, obstacles and surface conditions in order to mitigate risk and avoid an unfavourable situation.

About this report

Decisions regarding whether to conduct an investigation, and the scope of an investigation, are based on many factors, including the level of safety benefit likely to be obtained from an investigation. For this occurrence, no investigation has been conducted and the ATSB did not verify the accuracy of the information. A brief description has been written using information supplied in the notification and any follow-up information in order to produce a short summary report, and allow for greater industry awareness of potential safety issues and possible safety actions.
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1. Brownout condition: is an in-flight visibility restriction due to dust or sand in the air. In a brownout, the pilot cannot see nearby objects which provide the outside visual references necessary to control the aircraft near the ground.  This can cause spatial disorientation and loss of situational awareness leading to an accident.
2. Collective: a primary helicopter flight control that simultaneously affects the pitch of all blades of a lifting rotor. Collective input is the main control for vertical velocity.

What happened

On 5 May 2020, a Gippsland Aeronautics GA-8 was scheduled to operate a charter flight from Elcho Island to Ramingining, Northern Territory.

During the boarding process, the pilot asked the single passenger whether there were any dangerous goods in their luggage. The passenger proceeded to check the luggage and willingly handed over two spray cans with flammable contents. Following this, the pilot loaded the luggage into the aircraft.

As the aircraft climbed through approximately 4,000 ft, fumes were detected in the cabin described as smelling of solvent. At this time, the pilot became light-headed and adjusted the air vent to ensure fresh air was coming into the cabin. The pilot directed the passenger to check through the luggage for the source of the fumes. The passenger returned with a plastic container of glue, which had subsequently leaked. The pilot completed the fumes checklist and jettisoned the container safely out of the aircraft while operating over water.

Safety message

This incident highlights the importance of ensuring that all items taken on board an aircraft do not pose a safety risk to the flight. More information regarding dangerous goods can be found on the CASA website, including the Can I pack that? dangerous goods app for passengers.

About this report

Decisions regarding whether to conduct an investigation, and the scope of an investigation, are based on many factors, including the level of safety benefit likely to be obtained from an investigation. For this occurrence, no investigation has been conducted and the ATSB did not verify the accuracy of the information. A brief description has been written using information supplied in the notification and any follow-up information in order to produce a short summary report, and allow for greater industry awareness of potential safety issues and possible safety actions.

What happened

On 22 April 2020 at about 2323 Eastern Standard Time, the crew of a Leonardo S.p.A. Helicopters AW139 was conducting a mission involving the insertion of paramedics into a remote area in support of bushwalkers who had requested assistance. A short time after the safe insertion by hoist of the paramedics and their equipment, the paramedics requested that the helicopter return to overhead their position to assist with illuminating the area.

As the helicopter moved into position, the hoist operator positioned himself to use the hoist downlight for the illumination task. This involved him holding the hoist control pendant in his left hand and reaching for the search light directional control switch on the hoist panel with his right hand. At this moment, the helicopter experienced a gust of wind that disturbed the steady hover and caused the hoist operator to partially lose his balance.

In an attempt to stabilise himself, he held the door with his left hand and his right hand remained on or near the hoist control panel. As he was looking outside, the hoist operator’s gloved hand or wrist inadvertently flicked up the cable cutter guard and depressed the cable cutter switch in one movement, severing the hoist wire and resulting in the hook assembly falling to the ground.

Figure 1: Hoist control panel

Source: Operator

Operator’s investigation

The proximity of the cable cutter guard to the searchlight directional control switch has been assessed by the operator as an issue since 2016 with various procedural controls being enacted and/or refreshed at various times. A Civil Aviation Safety Authority‑approved modification was applied to the original panel to reduce the risk of inadvertent cable cut activation, which included the cable cut shroud as well as restraint of the intercom system lead. This did not completely eliminate the risk, but did provide a measure of design protection.

Although numerous actions to reduce the risk of inadvertent cutter activation have been recorded in the operator’s safety management system since 2016, the operator considers that a design relocation of the searchlight control switch would reduce the risk of inadvertent activation to as low as reasonably practicable.

Safety action

As a result of earlier occurrences, the operator implemented an engineered risk reduction solution on their fleet in 2017 that included a shroud around the cable cut switch (Figure 2 left). This shroud was present during this occurrence.

The manufacturer released a service bulletin in September 2019 that introduced the optional installation of a hoist cable cutter frame ‘to prevent inadvertent cable cut lifting actions on the hoist control panel’ (Figure 2 right). Following this occurrence, the manufacturer issued revised alert service bulletin 139-637 in June 2020 to mandate the information from operational to mandatory, and provide modification instructions for installation.

The European Union Aviation Safety Agency also issued airworthiness directive no. 2020-0131 to require installation of the frame.

Figure 2: Operator’s solution - shroud around cable cut switch (left)

Manufacturer’s solution - frame around cable cut switch (right)

Source: Operator (left) and Leonardo Helicopters Service Bulletin 139-557 (right)

The aircraft operator advised the ATSB that in response to this recent occurrence they have undertaken a preliminary assessment to have the searchlight control switch moved from the hoist control panel and have it incorporated into the hoist operator’s pendant control. This will remove the need for the hoist operator to have their hand in close proximity to the cable cut switch on the hoist control panel while operating the searchlight directional switch.

Safety message

This incident serves as a reminder for all crew members that ergonomic aircraft characteristics may pose a potential hazard to the safe operation of the aircraft or its systems. Identification and communication of such hazards allows safety action to mitigate the associated risk.

About this report

Decisions regarding whether to conduct an investigation, and the scope of an investigation, are based on many factors, including the level of safety benefit likely to be obtained from an investigation. For this occurrence, no investigation has been conducted and the ATSB did not verify the accuracy of the information. A brief description has been written using information supplied in the notification and any follow-up information in order to produce a short summary report, and allow for greater industry awareness of potential safety issues and possible safety actions.

What happened

On 20 February 2020 at about 1322 Eastern Daylight-saving Time, the pilot of an Airbus Helicopters AS 350 B3 was conducting external load activities at the Rocket Point walking track near Wentworth Falls, New South Wales.

As the remote hook, slung 150 ft below the helicopter lifted a 122 kg load of pipe, the pilot checked the rigging and slowly accelerated the helicopter into forward flight. As the pilot observed the load was stable, the helicopter was accelerated to 40 kt. A short time later, the load was inadvertently released from the hook and fell approximately 1,000 ft into unoccupied bushland.

Operator’s investigation

The operator conducted an in-depth investigation into this occurrence and determined that there were three significant factors that contributed to the load release. They were unable to establish a clear single cause as to what precipitated the occurrence.

The first contributing factor was the use of load beam part number (P/N) 290-683-00, which is of a different design to the normal in-service load beam P/N 290-683-02, specifically in the length of the beam (Figure 1) and slight variation in geometry. According to the manufacturer’s manual, the shortened load beam can be retrofitted to different P/N cargo hooks, however the load ring warning decal that specifies a smaller diameter shackle must be displayed. The cargo hook and load beam in use at the time of occurrence had incorrectly been marked with warning decal for the longer beam design (this contravened the manufacturer’s manual by not displaying the correct load ring warning decal). This is how the operator received the hook back from a routine equipment servicing in 2017.

The load beam that was in use has approximately 30 mm reduced beam length and different geometry to the more commonly used load beam, further increasing the likelihood of dynamic rollout occurring.

Dynamic rollout (or ring rollout/D-ring reversal) is a phenomenon that can be described as the unintended release of the primary engaging ring from a winch or cargo hook that may occur after a momentary unloading situation. An unloading event permits a dynamic condition allowing the ring to travel up and flip over the beak (tip) of the hook and come to rest on the spring-loaded keeper. The ring is now only supported by the spring-loaded keeper. When the load is re-applied, the spring-loaded keeper allows the ring to fall free from the hook, thereby inadvertently releasing the load.

Figure 1: Remote Hooks – the different load beams

Source: Operator

Secondly, it had become common practice for ground staff to utilise the method of attaching loads by attaching the strop loop directly to the hook’s load beam. As the radius of the loop in the nylon strop is greater than the length of the load beam, the likelihood of dynamic rollout occurring significantly increases. The operator had prepared an internal safety alert stipulating that a correctly sized shackle must be used when attaching loads to the load beam, however due to delays this was not released by the time of the occurrence.

Lastly, with the four strop loops of the load within the hook, it is possible that this created an overcrowding situation which could have prevented the keeper from correctly operating and/or being less visible to the ground crew if the strops had been placed on the hook correctly.

While the operator was unable to determine the exact cause for the inadvertent release of the load, the operator concluded it was reasonable that the load dropped due to dynamic rollout or due to the incorrect rigging of the nylon load strops to the shortened load beam. Dynamic rollout is more likely, as it is a known fault to occur when using the nylon strops without shackles. The use of the remote hook with a shorter load beam further exacerbated the situation leading to the loss of the load.

Safety action

As a result of this occurrence, the aircraft operator has advised the ATSB that they have updated their operations manual procedure to prevent unintentional release from the remote hook. Specifically, this involves the use of a self-locking hook and swivel with a correctly sized shackle as the single attachment to the remote hook.

Figure 2: Remote Hook lifting load with self-locking hook and swivel

Source: Operator

Safety message

This incident serves as a reminder for both ground and aircrew members that while conducting sling and winch operations, there are potential hazards to the safe completion of the task. Identification and communication of such hazards allows safety action to mitigate the associated risk. Further information on dynamic rollout and prevention can be found in CASA’s Airworthiness Bulletin 25-006.

About this report

Decisions regarding whether to conduct an investigation, and the scope of an investigation, are based on many factors, including the level of safety benefit likely to be obtained from an investigation. For this occurrence, no investigation has been conducted and the ATSB did not verify the accuracy of the information. A brief description has been written using information supplied in the notification and any follow-up information in order to produce a short summary report, and allow for greater industry awareness of potential safety issues and possible safety actions.