What happened

On 1 May 2021, at about 1200 Eastern Standard Time,^[1] a Raytheon B200 aircraft was being prepared for a flight from Brisbane to Rockhampton, Queensland. The forecast weather indicated light showers of rain; however, prior to departure, heavy rain showers passed over the airport.

Upon reaching the planned cruise level of flight level^[2] 260, the pilot discovered that the rudder trim was ‘frozen solid’ and could not be manipulated. The outside air temperature was -25 °C. Suspecting icing, the pilot commenced a descent and noted progressive improvement in the operation of the rudder trim once the aircraft descended into positive temperatures.

The pilot reported that normal trim operation resumed during the approach and landing. A post-flight inspection was conducted and no defects were found with the trim system.

Icing history

B200 aircraft have a known history of elevator trim icing. This has generally been found to be attributable to water freezing in the trim actuator gears and bushes, which were then redesigned to minimise the effects of ice accretion with a design that allowed the gears to crush formed ice.

Water freezing in the hinges was a problem first raised in 1981 in King Air Communique 57, and later Communique 98-002 identified piano hinges as an area prone to icing. This type of hinge is also used in the rudder trim tabs (Figure 1). The solution was to incorporate a regular lubrication schedule with a suitable grease that prevented water penetration of the hinges. Communique 90-002 included:

We have found that pressure washing of the elevator trim tab hinge washes out the lubricant, allowing moisture to enter the hingeline lugs and freeze at altitude. Even if you don't pressure wash, effects of the environment can cause the lubricant to dissipate over time and be replaced by water during foggy, misty, or rainy conditions. It is very important to re-apply the lubricant on a regular basis and lubrication schedules will vary according to the environment in which the aircraft is operated.

Both the elevator trim and rudder trim hinges have a standard lubrication interval of 200 hours, which the operator was complying with. The operator experienced a similar occurrence earlier in the year in a different B200 aircraft. It advised that although the incident aircraft were within the recommended lubrication interval, both occurrences of suspected icing followed periods of heavy rainfall on the ground prior to take-off.

Figure 1: B200 Rudder trim tab hinge location

Source: Textron Illustrated Parts Catalogue, annotated by the ATSB

Previous similar occurrences

In the 10 years prior to this occurrence, the ATSB received 48 airframe icing notifications, 22 of which involved icing of the flight controls. Aircraft that are part of the King Air series^[3] accounted for approximately 15 per cent of total airframe icing reports but over a quarter (27 per cent) of all incidents that involved the icing of control surfaces. There were no records related to icing in the Civil Aviation Safety Authority defect register for the same period.

Two thirds of the aircraft that encountered control icing were regional airline turboprops and utility aircraft (such as the King Air) that typically operate at flight levels. Table 1 shows the aircraft that have reported icing control events since 2011.

Table 1: Control icing events by aircraft type

Operational exposure

The Bureau of Meteorology has produced educational material on the hazards associated with airframe icing, which stated that icing conditions are only present in temperatures between 0 ºC and -40 ºC, with the highest risk occurring between 0 ºC and -20 ºC. These temperatures occur at the flight levels where turboprop aircraft typically operate (Figure 2).

Figure 2: The icing environment

Source: Bureau of Meteorology

Tail icing

Ice accumulation on the tail is not uncommon in known icing conditions^[4] and many light turboprop aircraft such as the B200 are fitted with de-ice equipment. This is typically installed on the leading edge of the wing or horizontal stabiliser but does not afford any useful protection to trim tabs located at the rear of the aerodynamic surface. Icing is often visible on the wings or windscreen, but tail icing is harder to diagnose due to the lack of visibility the pilot has of the tail section from the cockpit. As part of NASA’s in-flight icing research program, an Aircraft Icing Training course was developed that included early indicators and recovery techniques from ice-contamination tail stalls. Although this training focussed on the hazards of aerodynamic interruption due to ice accumulation, it did not refer to trim icing.

Safety action

The operator contacted the manufacturer’s field representative to confirm the correct grade of lubricant was being used and the maintenance schedule was in line with the manufacturer’s recommendations. Information about lubrication is contained in chapter 12 SERVICING – LUBRICATION SCHEDULE of the manufacturer’s maintenance manual.

Safety message

Without post-flight evidence of a defect, icing of control surfaces could go unreported. The ATSB encourages all pilots to report significant icing incidents to improve understanding of the impact icing-related occurrences may have on flight safety. This incident highlights the importance of operators tailoring service schedules to suit the environment in which the aircraft are operating.

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. Eastern Standard Time (EST): Coordinated Universal Time (UTC) + 10 hours.
2. Flight level: at altitudes above 10,000 ft in Australia, an aircraft’s height above mean sea level is referred to as a flight level. (FL). FL 370 equates to 37, 000 ft.
3. King Air Series: Produced by Beechcraft (and now Raytheon), the King Air family of aircraft is comprised of various twin-engine turboprop variants including the B200.
4. Icing conditions: Icing conditions typically exist in flight when the static outside air temperature is 5 ºC or below, and visible moisture (clouds, fog, rain, snow or sleet) are present.

What happened

On 20 June 2021, the Eurocopter AS350 helicopter was involved in lifting operations transporting materials to a worksite on Mount Difficult, approximately 38 km south-east of Horsham, Victoria. The lift operations were conducted by a single pilot, using a 100 ft line, and supported by a second pilot acting as ground crew. The ground crew member was also an experienced long line pilot. The two crew had swapped roles and worked extensively together throughout the project.

The pilot had completed eight lifts that day and at 1350 local time, after all required lifts had been completed, the helicopter returned to the Mount Difficult Helicopter Landing Site (HLS) near the worksite. The landing site was a confined area on the edge of a rock ledge with trees and shrubs nearby (Figure 1). The established procedure was to lower the remote hook and line to the ground before releasing the line from the belly of the aircraft at the lowest safe height. The helicopter would then reposition for an approach. This allowed the helicopter to approach the HLS without the 100 ft line attached.

The pilot placed the line to the south of the HLS and re-positioned to land. Most of the line was lying on the ground, but a small section of the line was suspended in a sapling 10­­­­­–12 ft right front of the aircraft nose. The aircraft landed clear of the line, and after receiving confirmation from the ground crew member that the landing position looked safe, the helicopter was shut down.

As the engine spooled down the ground crew member commenced sorting and coiling the line into the back of the aircraft. This placed tension on the line between the coiled section in the helicopter and the looped section in the tree, thereby bringing the line into the path of the rotor disc. This was caught by a blade and subsequently entangled the rotor head. The line pulled the ground crew member’s arm upwards, snared their lower leg and body, before pulling them sideways along the ground.

The crew member sustained minor bruising to their face, right elbow, left leg and foot and was later cleared of concussion or serious injury. The line was later found to have wrapped around the mast, resulting in minor damage to the swashplate, mast, rotor head and main rotor blades.

Figure 1: Mount Difficult HLS

Source: Supplied by operator, annotated by the ATSB

Safety action

The ATSB has been advised the operator has implemented the following safety action in response to this occurrence:

• A safety briefing was conducted with all company pilots, which included an incident analysis, review of procedures and safety measures. A new requirement was introduced that now states that objects should not be raised above shoulder height while under the rotor disc.
• The Flying Operations Manual and relevant Aircraft Operations Plans (including Daily Safety Briefing and Emergency Plan) were updated to specifically clarify that:
  • movement of equipment, including aerial work equipment, into and out of aircraft should be conducted while the rotor is stationary unless strictly necessary; and
  • coiling of lines and the assembly of equipment must be completed outside the rotor disc unless the rotor is completely stationary.

Safety message

Despite having produced detailed safety assessments and extensively documented operating procedures, an unintentional decision error resulted in a serious incident. Operators involved in complex operations need to remain vigilant when monitoring potential hazards around the area of operations, especially when equipment is to be stored or positioned close to operating aircraft.

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 the 24 August 2021, at about 1853 Eastern Standard Time,^[1] the flight crew and an associated ground crew of a Finmeccanica Helicopter Division AW139 were conducting night vision winch training at the main helipad of Bankstown Airport, New South Wales. The recorded wind was gusting to 25 kt. The pilot of the AW139 was conducting a hover at approximately 15 ft above the helipad when a ground crew member alerted the flight crew of a loose gable marker about 20 m from the hovering helicopter.

The pilot landed the helicopter and requested the ground crew to investigate the gable marker. The ground crew identified a Cessna Aircraft Company 152 upside down approximately 55 m from the helipad. The Cessna 152’s right main wing tie down rope had snapped and the left tie down rope had pulled through the wing tie down point. The pilot of the helicopter ceased the training activity and taxied back to the apron.

In a separate incident on 31 August 2021 at about 1325 Western Standard Time,^[2] the pilot of a Cessna Aircraft Company 152 taxied to the runway 24 runup bay for pre-flight engine runs at Jandakot Airport, Western Australia. The pilot parked in the runup bay approximately 15 m behind a Piper Aircraft Corp PA-42 that had its engines shut down. The PA-42 was parked in a south‑west direction with its nose into wind. The pilot of the Cessna 152 noticed two engineers working on one of the PA-42 engines. During the subsequent Cessna 152 engine checks, the pilot felt a gust of wind and noticed that the PA-42 had started both engines. This resulted in the Cessna 152 being flipped over onto its roof by the propeller wash from the PA‑42. There were no injuries to the pilot of the Cessna 152 but the aircraft sustained significant damage.

Safety message

Although it could not be determined that the rotor wash was a factor in the incident at Bankstown Airport, these two incidents highlight the significant effect propeller, rotor wash, and prevailing wind conditions can have on light aircraft. Flight and ground crews are reminded to remain aware of their surroundings at all times during operation or testing of an aircraft, particularly when other aircraft or personnel are nearby. This can include the re-evaluation of aircraft positioning during engine testing to prevent propeller wash from affecting nearby aircraft.

Crews are also reminded of the importance of a regular inspection of tie down ropes and chains, and to use sufficient tie down techniques when securing aircraft at the end of flight activities.

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.

1. Eastern Standard Time (EST): Coordinated Universal Time (UTC) + 10 hours
2. Western Standard Time (WST): Coordinated Universal Time (UTC) + 8 hours/a>

What happened

On 3 August 2021, a 63 m landing craft prepared to depart Masons Wharf in Smiths Creek, Cairns, where the craft was berthed starboard side alongside with a patrol vessel berthed immediately astern and downstream of it (Figure 1, position 1). To proceed to sea, the landing craft needed to turn downstream off the wharf and then sail out of the creek.

Figure 1: Sequence of events

Relative size and position of vessels in diagram are approximate indications only

Source: Maritime Safety Queensland

At 1615 local time, the landing craft cast off from the wharf. The tide was flooding with high tide predicted at 1925. From the landing craft’s navigational bridge, the master initially manoeuvred the craft about 8 m laterally off the wharf. The master then altered the craft’s heading slightly to starboard before operating astern propulsion on both main engines. This plan involved allowing the flooding tide to act on the craft’s starboard quarter to assist with the manoeuvring away from the wharf as it came astern (Figure 1, position 2). 

Moments later, the master observed that the south-easterly wind acting on the landing craft’s port side was counteracting the effect of the tidal stream, making it difficult to manoeuvre away from the wharf and the patrol vessel as planned. Consequently, in an effort to drive the craft’s stern further into the channel where it could be safely turned around, the master increased astern propulsion (Figure 1, position 3).

At that time, a crew member stationed aft with a radio began reporting the distance from the creek’s eastern shoreline, thickly wooded with mangroves, to the master. Another crew member with a radio was stationed forward to report clearances from the bow. As the radios of the master and crew were on the same simplex frequency,^[1] transmissions from aft were interfering with those from forward. Consequently, the master resorted to making his own visual appraisal of the clearance from the patrol vessel ahead and remained focused on executing the turn, but not the decreasing clearance from the mangroves being reported. Shortly after, the landing craft’s stern ran into the mangroves (Figure 1, position 4 and Figure 2) before the master took action to manoeuvre clear and sail down the creek. The landing craft was found to remain in good working order afterwards and proceeded on its voyage. 

Figure 2: Landing craft running into mangroves

Source: Landing craft operator

Safety action

The landing craft’s manager advised that as a result of this occurrence, a review of mooring procedures has been commenced, including communication protocols between crew members during operations.

Safety message

This occurrence highlights the importance of appropriate planning and risk assessment prior to vessel manoeuvring operations while also underscoring the importance of effective onboard communication procedures. These measures are relevant even for familiar, routine operations. A comprehensive appraisal might include an assessment of wind, tide and sea conditions in relation to the proximity of navigation hazards and the available manoeuvring room. 

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.

__________

1. Simplex operation means the radio stations are communicating with each other directly, on the same simplex radio frequency. Each station must take turns transmitting on the same frequency and only one radio transmission can be received by another station at a time.

What happened

On 16 August 2021, a flight instructor and student pilot prepared a Piper PA-28 aircraft for a training flight departing from Wagga Wagga Airport. 

At about 0900 local time, during taxi and prior to take-off, the instructor opened the cabin heater vent to demist the cabin windows. At approximately 0930, during initial climb, with the student at the controls, the instructor began feeling slightly dizzy and unwell. They inspected the aircraft’s disposable carbon monoxide (CO) chemical spot detector and observed that it had darkened, indicating the presence of elevated CO levels in the cabin (Figure 1).

Figure 1: The aircraft’s CO spot detector during the flight (left) and after landing (right)

Source: Aircraft owner

The instructor immediately alerted the student to the indication, closed the cabin heater vent and opened the cockpit’s fresh air vents and storm window. Upon being alerted by the instructor, the student informed the instructor that they were not experiencing any symptoms of CO poisoning. The student continued to fly the aircraft while the instructor provided directions to return to the airport, where the aircraft was landed safely.

After landing, the instructor continued to feel the effect of CO poisoning and was taken to hospital for treatment and released soon after. 

An inspection of the aircraft’s exhaust and cabin heater systems did not identify any defects. Prior to returning the aircraft to service, engine ground runs were carried out to determine cabin CO levels. During these runs, cabin CO levels were low at all power configurations and heater settings.  

Safety action

As a result of this occurrence, the owner of the aircraft is assessing the feasibility of installing active-alarm cockpit CO detectors throughout its fleet of piston-engine aircraft.

Safety message

Carbon monoxide is a colourless, odourless and poisonous gas which is formed through the incomplete combustion of carbon-containing materials, including aviation fuel. The exhaust fumes from piston engines contain high concentrations of CO. The presence of dangerous CO levels within a confined aircraft cabin may not be detected until the occupants begin to develop physical symptoms such as nausea, headaches, dizziness, shortness of breath and blurred vision along with cognitive effects such as confusion and impaired judgement. ATSB Safety Advisory notice AO-2017-118-002 Are you protected from carbon monoxide poisoning? strongly advises that piston-engine aircraft be equipped with a digital cockpit CO detector with an active warning to alert pilots to elevated CO levels in the cabin. 

If a pilot detects any abnormal odours or experiences symptoms consistent with CO poisoning, they should ensure that the cabin heat vent is closed, open all fresh air vents and windows and take action to land as soon as possible using all available resources for assistance.

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 28 June 2021, at about 0805 local time, the pilot of a Cessna 210N aircraft was conducting a charter flight from Kununurra to Berkeley River Lodge aeroplane landing area (ALA), Western Australia, with four passengers on board.

On arrival at Berkeley River Lodge, the pilot joined the downwind leg of the circuit for runway 11. The landing gear had been extended about 2 NM prior to entering the circuit. The pilot conducted a circuit and actioned the pre-landing checklist. Approaching the threshold of the runway, the pilot elected to conduct a go-around due to windshear and gusting crosswinds.

During the subsequent initial climb, the pilot retracted the landing gear and continued to fly the circuit for a second approach. The pilot reported that, during the second circuit, they were concentrating on the gusty wind conditions and omitted to refer to the pre-landing checklist. On final approach, the pilot thought that the gear was already down from the previous circuit and as a result, the aircraft landed with the wheels up. The pilot reported hearing activation of the landing gear warning horn during the flare, however, mistakenly believed it to be the stall warning horn.

The aircraft sustained minor damage to the propeller and underside of the fuselage.

Safety message

This incident highlights the importance of managing distraction. During times of high workload, distraction can often lead to human error and simple tasks such as selecting the landing gear could be unintentionally omitted. In addition, due to this a pilot may not distinguish the difference between the sound of the stall and landing gear horns. Pilots should be mindful of completing all normal pre-landing checks even during an abnormal situation.

Wheels-up landings are not uncommon. Table 1 shows the number of wheels-up landings reported to the ATSB each year since 2012. The Flight Safety Australia article, Those who won’t: avoiding gear-up landings includes additional information to assist pilots in avoiding these incidents.

Table 1: Wheels-up landings per year

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 April 2021, a Fairchild SA227 aircraft taxied at Townsville Airport, for a freight charter flight to Brisbane, Queensland. At about 1854 Eastern Standard Time,^[1] air traffic control (ATC) cleared the aircraft to line up on runway 01 from taxiway Alpha 1.

It was dark, as last light ^[2] had occurred approximately 56 minutes earlier. Rain showers had also passed through the area intermittently during the preceding 30 minutes. The automatic terminal information service^[3] reported runway conditions at the time as wet, with visibility reducing to 4 km in rain and scattered cloud at 700 ft above ground level.

As the aircraft was entering the runway, and 20 seconds after issuing the line-up clearance, ATC advised the pilot that the aerodrome QNH^[4] had changed. This change required the pilot to adjust the altimeter datum that had been set prior to line-up. Twelve seconds later, ATC cleared the aircraft for take-off. As the pilot read back this clearance, completed the before take-off drills, and taxied the aircraft into position on the runway, they reported becoming aware that the aircraft ‘had deviated from the lead-in line’ and ‘started correcting the turn immediately to…regain a track to the centreline’. Having made this correction, and assessing that the runway centreline would be regained shortly after beginning the take-off roll, the pilot commenced a rolling take-off and reported no unusual indications throughout departure.

During routine aerodrome inspections carried out 48 minutes after the aircraft departed, it was discovered that an above ground runway light on the left side of runway 01 had been struck and damaged by an aircraft (Figure 1).

Figure 1: Aircraft tyre tracks and runway light damage

Source: Townsville Airport, annotated by the ATSB

Pre-flight inspections carried out on the aircraft the next day found damage to a propeller blade on the left engine that was consistent with the propeller impacting a foreign object (Figure 2).

Figure 2: Damage sustained to aircraft’s propeller

Source: Operator, annotated by the ATSB

Subsequent engineering inspections by the operator discovered ‘slight witness marks’ of yellow paint on the left main landing gear that was the same colour as the above ground runway lighting fixtures on Townsville’s runway 01.

The operator found that the clearance between an empty SA227 propellor’s tip and the ground was 260 mm. The height of the aerodrome light that was struck was 250 mm. However, it was concluded that a combination of the 789 kg of freight that was on board the aircraft at the time of the occurrence, and the normal range of oleo compression that would be expected during take-off, would reduce the clearance between the propellor blade and the runway light sufficiently to allow a propellor blade to strike the light.

As the landing gear on the SA227 is mounted in the engine nacelle directly behind the propeller, the operator concluded that a propellor blade had struck the runway light during the aircraft’s take-off run, partially destroying the light. The left main wheels then passed over the mounting location of the runway light, impacting the remains of the runway light fixture and leaving the paint witness marks visible on the landing gear assembly. This also resulted in the tyre tracks that remained visible on the runway surface the next day (Figure 1).

The operator concluded that the pilot had become spatially disorientated during the runway line-up sequence, and commenced the take-off from a position further left of the runway centreline than they had perceived (Figure 3), resulting in a propeller blade on the left engine contacting the runway light. An internal investigation by the operator found that a number of factors contributed to the aircraft striking the runway light on take-off. These included:

• the runway lead-in lighting not extending to the runway centreline when entering the runway from the Alpha 1 holding point
• distraction and high workload of the single pilot while completing the line-up sequence
• difficulty in sighting the painted runway lead-in lines due to low lighting conditions and standing water on the ungrooved section of the runway’s surface.

It was further reported by the pilot that the design of the runway, and the wider paved section at the runway’s end to accommodate military aircraft movements, contributed to their not identifying the runway misalignment.

Figure 3: Approximation of planned, perceived, and actual aircraft path during line-up

Source: Google earth, annotated by the ATSB

Historical context

Townsville Airport is a joint user facility with both military and civilian aircraft movements. Runway 01/19 is equipped with an Operational Readiness Platform (ORP) (Figure 4) which is a large, paved apron section at either end of the runway, where military aircraft can be parked. The ORP section is only intended for use by military aircraft, and as such, recessed lighting and markings indicate the normal runway dimensions within this area, as well as the outer edges of the ORP area. At the end of the ORP area, the pavement width reduces to normal runway dimensions and lighting.

At the southern end of the runway, runway lighting indicates the correct path for an aircraft to vacate the runway onto taxiway Alpha 1. However, this lighting is unidirectional, and does not indicate the correct path for an aircraft to take when lining up on the runway from the direction of taxiway Alpha 1 (Figure 4).

Figure 4: Runway lighting and layout of departure end of Townsville Airport Runway 01

ORP area illustrated, as well as the runway lead-in lighting that is not visible to an aircraft entering the runway from taxiway Alpha 1

Source: Townsville Airport, annotated by the ATSB

This is the second occurrence of this type on Townsville’s runway 01. An ATSB investigation examined a previous occurrence on 11 February 2009 that involved a Bombardier DHC-8 aircraft taking off at night (AO-2009-007). The DHC-8 had also lined up and commenced its take-off roll on the runway 01 edge lighting, after entering the runway from holding point A1. The DHC-8 crew had realised their misalignment during the take-off roll, and rejected the take-off after striking a runway side light with the landing gear.

As a result of this and similar occurrences at other airports, the ATSB undertook Aviation Research and Analysis Report Factors influencing misaligned take-off occurrences at night (AR-2009-033), which examined these types of incidents and their causes. This analysis identified eight factors that increased the risk of a misaligned take-off or landing. These factors were,

distraction or divided attention of the flight crew; confusing runway layout; displaced threshold or intersection departure; poor visibility or weather; air traffic control clearance/s issued during runway entry; no runway centreline lighting; flight crew fatigue; and recessed runway edge lighting.

A number of these factors were present during the take-off of the SA227:

• The pilot reported being distracted and ‘head down’ during the initial line-up sequence to configure the aircraft for take-off.
• Townsville’s runway 01 includes a wider ORP section at its end, which contributed to the pilot’s false perception that they had not travelled across the runway as far as they actually had during the line-up phase.
• The weather at the time, which was similar to that of the 2009 DHC-8 occurrence, was wet with rain intermittently reducing visibility.
• A change in local QNH had required ATC to contact the pilot during the line-up sequence, adding to the pilot’s workload during this phase.
• Townsville’s runway 01 does not have centreline lighting, which reduces the visual cues available to a pilot to confirm the correct runway orientation.
• Recessed runway lighting is used to denote the outline of the normal runway dimensions within the ORP area. This has the potential to contribute to spatial disorientation during the line-up phase, as this type of runway lighting is normally used to indicate the centreline on a runway equipped with centreline lighting.

With the exception of crew fatigue, seven of the eight major factors identified by the ATSB as increasing the risk of a misaligned take-off or landing were present in this occurrence.

Safety action

As a result of this occurrence, the aircraft operator has advised the ATSB that a Safety Advisory will be sent to all flight crew identifying the hazards associated with runway alignment on runways equipped with an ORP area. Flight crew have also been reminded of the importance of identifying and managing distractions, and of the option to delay take-off where there is any doubt about the aircrafts position during the line-up sequence.

Townsville Airport has advised the ATSB that it is currently reviewing the existing runway lighting arrangement on runway 01/19, with a view to ensuring that the runway lighting is sufficient to ensure correct alignment with the runway during line up.

Safety message

This incident highlights the potential hazards in runway misalignment, as well as the primary factors previously identified by the ATSB as contributing to these occurrence types. In addition, runways that are equipped with Operational Readiness Platforms pose additional challenges in correct runway identification and alignment.

It is also a reminder to crew of the importance in managing distraction and interruption during critical phases of flight. These threats will always be present in the operational aviation environment, but through effective identification and management, the potential impact on flight safety may be mitigated.

In this occurrence, the pilot correctly identified that they had lost situational awareness during line-up, but had elected to continue the take-off before re-establishing sufficient situational awareness of the aircraft’s position. By halting the line-up to fully re-establish situational awareness, the pilot may have been able to identify the runway misalignment prior to commencing the take-off roll.

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.

__________

1. Eastern Standard Time (EST): Coordinated Universal Time (UTC) + 10 hours.
2. Last light: when the centre of the sun is at an angle of 6 degrees below the horizon after sunset.
3. ATIS: the automated broadcast of information relating to operations at an airfield during tower hours.
4. QNH: the altimeter barometric pressure subscale setting used to indicate the height above mean sea level.

What happened

On 25 August 2021 at 1115 local time, a pilot and engineer were conducting an engine ground run of a Bombardier Challenger 600 aircraft on the apron at Essendon Airport, Victoria. The aircraft was privately owned/operated and had not conducted any flights since 2017.

The nosewheel was chocked, with the left seat foot brakes applied instead of the required parking brake due to previous issues with releasing the park brake. The Challenger’s two turbofan engines were successfully started with normal system indications, and the power levers moved to the low idle position. The power levers were then moved to the high idle position for a short time and then back to low idle, after which the aircraft moved forward and rolled over the chocks.

The pilot was applying pressure onto the left seat foot brakes, and tried pumping them, but the aircraft continued to move forward. The pilot then tried using the rudder pedals to steer toward a grass area off the apron without success. The Challenger hit a parked helicopter and another parked aircraft before rolling through a perimeter fence and colliding with a building (Figure 1), bringing the Challenger to rest about 30 seconds after it started to roll.

Figure 1: Challenger path

Source: Google Earth, annotated by the ATSB

The pilot shut down the left engine by moving its power lever to the idle cut-off position. The right engine power lever could not be moved into the cut-off position, so the pilot activated the right engine’s fire extinguishing system, which successfully shut down the engine. The pilot and engineer then exited the aircraft.

The aircraft received substantial damage to the nose, wing leading edge, and winglets. Post‑accident testing of the Challenger’s brake system could not be performed due to hydraulic system damage from the accident.

Safety action

The pilot and engineer are considering the use of additional chocks during aircraft ground running.

Safety message

It is important to follow all operational procedures during engine ground runs, especially those related to securing the aircraft from moving. Positioning the aircraft away from obstacles during the ground run, for example at an airport’s run-up area, can also reduce the risk of colliding with obstacles should the aircraft unexpectedly roll. If this occurs, flight and maintenance crew must be prepared to initiate emergency actions, such as engaging brake systems and immediately shutting down engines.

After an extended period of inactivity, it is important to conduct full system checks before operating an aircraft.

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 25 March 2021, at about 2130 Eastern Daylight-saving Time,^[1] following a rostered day of flying duties, the pilot of the Diamond DA42 aircraft commenced taxiing at Bankstown Airport, New South Wales, for a session of night circuits to maintain currency.

After the aircraft had rolled forward slightly, the pilot noticed they had left their iPad on the apron and decided to retrieve it before proceeding any further. The pilot engaged the park brake with both engines running and exited the cockpit onto the aircraft’s wing. While the pilot was on the wing, the aircraft moved forward, causing the pilot to lose balance and fall backwards onto the tarmac. The pilot sustained minor hand and leg injuries.

The parking area had a slight decline and the aircraft rolled down the slope. The right wing struck a hangar, and the aircraft went through a perimeter fence, resulting in minor damage to the wing tip and various panels around the nose section of the aircraft.

The pilot reported being unable to regain entry to the cockpit as it rolled away. Once the aircraft had stopped moving, the pilot entered the cockpit and shut down the engines before securing the aircraft.

Park brake

Operation of the park brake is achieved by applying pressure to the toe brake pedals and moving the park brake selector down until it catches. This traps the hydraulic fluid in the brake units and the wheel brakes stay on. The pilot reported being unsure if sufficient pressure was applied to the brake pedals when activating the park brake. The operator advised that following the incident, the park brake was checked and reported to be serviceable.

Fatigue

The pilot reported that at the time of the incident they had been awake for 17 hours. The ATSB publication Fatigue experiences and culture in Australian commercial air transport pilots references studies that found periods of extended wakefulness increase the risk of experiencing a level of fatigue demonstrated to adversely affect performance.

Safety action

As a result of this occurrence, the operator advised the ATSB that the company has introduced a refresher course for all flying staff regarding fatigue management and responsibilities.

Safety message

A more appropriate course of action would have seen the pilot shut down the engines before securing the aircraft with the park brake and then exiting the aircraft to retrieve the iPad from the apron. Lapses in decision making can result from extended periods of wakefulness. 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 safety concerns is Fatigue.

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. Eastern Daylight-saving Time (EDT): Coordinated Universal Time (UTC) + 11 hours.

What happened

On 14 March 2021, the pilot of a Kavanagh E-240 balloon was conducting a scenic flight over Melbourne, Victoria with 10 passengers on board.

Shortly before 0830 Eastern Daylight-saving Time ^[1] the balloon approached the planned landing area at Bulleen Park. To reach the landing area, the pilot needed to conduct a descent into a westerly wind. This resulted in the balloon descending over powerlines, which varied from the normal practice of passing over significant obstacles while in level flight. The powerlines were adjacent to the landing area, suspended between two high tension towers (Figure 1), and displayed on the pilot’s iPad.

Figure 1: Incident location showing intended landing area, powerlines and approximate balloon flightpath

Source: Google Earth, annotated by the ATS

The pilot conducted the descent so as to pass above the high voltage wires that they could see. However, due to local lighting conditions, approaching the powerlines in a descent and vegetation in the area, the pilot did not see an earthing wire ^[2] that ran 7.43 m above the high voltage wires.

During the descent, the balloon’s basket struck the earthing wire, which arrested its forward momentum. The basket remained held against the earthing wire, and above the high voltage wires, for about 20 seconds as the pilot engaged the burner to initiate a climb. The balloon then climbed free of the earthing wire, sustaining minor damage in the process.

The flight proceeded to an alternative landing area at Westerfolds Park without further incident. The pilot and passengers were uninjured. The balloon sustained damage to five of the 20 woven stainless steel flying lines, the suede covering on a burner support rod and the balloon’s fabric scoop (Figure 2).

Figure 2: Damage to balloon and basket

Source: Kavanagh Balloons, annotated by the ATSB

Safety action

As a result of this incident, the operator has advised the ATSB that it has taken the following safety actions:

• instituted a policy that if wind conditions do not permit an approach to this landing area to be conducted in level flight, with a minimum of 40 m clearance above powerlines, the flight is to proceed to the next suitable landing site
• reminded pilots that flight should ‘always be carried out with extreme care and consideration to avoid powerline contact’ in line with the operations manual.

Safety message

This incident is an important reminder of the hazards associated with operations around powerlines. It is also a reminder to balloon operators of the importance in planning descents to take place when downwind of any significant obstacles.

In this incident, the pilot had operated into this landing area multiple times and was familiar with the powerlines but struck them anyway. This is not uncommon, as ATSB research indicates that in 63 per cent of wirestrike incidents the pilot was aware of the powerlines that were subsequently struck.

The Australian Ballooning Federation’s Pilot Circular No 18, dated February 2012, also highlights the following hazards to pilots in operations around powerlines that are relevant to this occurrence:

• Complacency: Familiarity and repetition regarding operation and location can lead to complacency. Be aware of this and hence be vigilant. Data shows the worst accidents are often made by the most experienced and skilled operators.
• Reduced visibility: Sun, mist, haze, contrast. Be vigilant and conservative under these conditions.
• See and avoid scanning technique: Avoid focusing too long on close objects or scanning quickly left and right. Focus at a distance and move attention slowly over small arcs pausing briefly for a few seconds each time to closely examine the area.

The ATSB publication Avoidable Accidents No. 2 – Wirestrikes involving known wires provides further guidance in mitigating the risk to operations around powerlines.

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. Eastern Daylight-saving Time (EDT): Coordinated Universal Time (UTC) + 11 hours.
2. An earthing wire does not carry electrical current, its purpose is to protect the other conductor wires from lightning strikes.