On 12 June 2012, a Robinson Helicopter Company R44 Raven 1, registered VH-HIE (HIE), departed Moorabbin, Victoria with one person on board to conduct a private flight to a property at Moolort, about 23 km east of Maryborough aerodrome, Victoria.
During the flight, the pilot decided to check on the progress of a bore under construction about 2 km west of the intended destination. The pilot landed at the bore site without incident and after only a short time on the ground, decided to depart in the same direction as his approach.
At about 1130 Eastern Standard Time, the helicopter became airborne and as it transitioned from hover to forward flight, the pilot saw a single strand powerline directly ahead. The helicopter hit the powerline and subsequently impacted the ground. The pilot was not injured, however the helicopter was seriously damaged.
The accident highlights the importance of a proper reconnaissance when flying in a wire environment and remaining focused only on operational tasks. The pilot's reaction to the wirestrike, which was to continue to fly the aircraft to the ground, assisted in him being able to land without injury.
On 4 June 2012, a Cessna Aircraft Company 182Q, registered VH-CWQ, with the pilot the sole person on board took off from Walgett in good weather conditions for a flight to Mudgee, New South Wales (NSW), initially climbing to 5,500 ft. During the flight, the cloud base lowered, and the aircraft was descended until it was flying about 1,000 ft above flat terrain, either close to or in the cloud. The aircraft impacted a rock face in mountainous terrain near Tooraweenah, NSW. The pilot sustained fatal injuries and the aircraft was destroyed.
What the ATSB found
The ATSB found that the risk to flight was increased by deteriorating weather conditions. The risks associated with continuing a flight under these circumstances are highlighted in the ATSB Transport Safety report AR-2011-050, Accidents involving Visual Flight Rules (VFR) pilots in Instrument Meteorological Conditions. Additionally, influences on pilot decision making behaviours are described in the ATSB Research Investigation report B2005/0127, General Aviation Pilot behaviours in the face of Adverse Weather.
Safety message
This accident provides a reminder to pilots of the insidious risks associated with reduced forward visibility when flying in or near the cloud base. The benefits of leaving a Flight Note with a suitable person in terms of ensuring the early commencement of a search for an overdue aircraft are also evident.
Pilots conducting VFR flights should remain aware that once they fly into weather conditions with reducing forward visibility, their ability to manoeuvre around approaching obstacles could be severely limited because obstacles may not be seen until they are too close to avoid. Such collisions are not often survivable.
The pilot comenced duty at 0230 hours for an 0300 departure. He
arrived back at Kalgoorlie at approximately 0830 having completed
nearly four hours flying. He then departed Kalgoorlie again at 0930
in VH-CLL for a flight to Laverton and return. This was the first
flight for the day in CLL, on which a 100 hourly inspection had
been completed the previous day. The aircraft left Kalgoorlie on
this trip with full fuel tanks which is 337 L and sufficient for up
to six hours flying. The planned time for the trip was 104 minutes.
The pilot had a four hour break
at Laverton in air conditioned sleeping accommodation. He said
that he used this time to catch up with paper work.
At 0027 Western Standard Time on 1 June 2012, a Boeing 717 aircraft, registered VH-NXO and operated by Cobham Airline Services, was conducting an instrument approach to land on runway 03 at Perth Airport after a flight from Paraburdoo, Western Australia.
The approach was being conducted in instrument meteorological conditions. When the aircraft was at the decision altitude, the crew initiated a missed approach procedure as they had not obtained visual reference with the runway. Almost immediately, the crew obtained visual reference with the runway, discontinued the missed approach procedure and landed.
What the ATSB found
The onset of fog at Perth Airport at the estimated time of arrival was not forecast until after the aircraft had passed the point in the flight when it had insufficient fuel remaining to divert to a suitable alternate aerodrome. Before that point, there had been no requirement for the aircraft to carry fuel to continue to a suitable alternate.
Under the circumstances, the flight crew considered that the better option was to discontinue the missed approach procedure and land, in spite of the aircraft being in an unstable condition due to the initiation of the missed approach.
Safety message
This occurrence highlights that during a flight, the forecast weather at the destination may change and the advisability of obtaining the most up-to-date weather forecasts. However, pilots should be alert to the fact that the actual weather can differ significantly from forecasts.
The occurrence also highlights the risk of an unstable approach from not following a missed approach through to its conclusion. Unstable approaches are a frequent factor in approach and landing accidents, including controlled flight into terrain. The Flight Safety Foundation has developed an Approach and Landing Accident Reduction Tool Kit aimed at reducing the risk of approach and landing accidents. The toolkit can be found at Flight Safety Foundation website.
Context
Pilot information
The flight crew consisted of two pilots who held endorsements on the aircraft type.
The captain had been flying with the operator for 17 years and had a total of about 17,000 hours aeronautical experience in a range of different aircraft types. The captain had been flying this aircraft type for about 18 months, and a different jet airliner type for 8 years before that.
The first officer (FO) had been with the operator for about 5 years and had a total of about 10,000 hours aeronautical experience, with about 2,500 hours on this aircraft type. Before then, he had been flying turboprop aircraft.
Meteorological information
When planning for the return flight at Paraburdoo, the Perth aerodrome forecast (TAF)[7] and the trend forecast (TTF) did not contain any forecast operational requirements for this aircraft to carry sufficient fuel to fly to an alternate aerodrome. At 2300, 5 minutes after take-off, the Perth TTF changed with the forecast onset of fog 65 minutes after the estimated time of arrival (ETA).
At 0010, which was about the time when the aircraft commenced its descent and shortly before the aircraft no longer had sufficient fuel to divert safely to a suitable landing aerodrome, the Perth TAF was amended to indicate a requirement for the carriage of sufficient fuel to divert to an alternate airport on the basis of more than four OKTAS[8] of cloud with a base below the alternate minimum of 700 ft above the aerodrome reference point. The forecast also predicted that 35 minutes after the aircraft’s ETA, there was a 30 per cent probability of fog reducing the visibility to 300 m, which was below both the alternate and landing minimums for runway 03.
Soon after, at 0014, a TTF SPECI[9] was issued for Perth Airport indicating that the visibility had reduced to 7,000 m and the airport was partially covered in fog. The observed visibility, as reported on the TTF SPECI issued at 0030, which was soon after the aircraft’s landing time, was 900 m in fog.
Operational information
Information sources relating to alternate aerodrome requirements
Aeronautical Information Publication Australia (AIP) section ENR 1.1, 58.2 Weather conditions, paragraph 58.2.9 related to the application by crews of forecast weather conditions when determining the need to allow for an alternate aerodrome. In this regard the AIP stated that:
Flights which will be completed within the time of validity of the TTF may be planned wholly with reference to the destination TTF.
Operator procedures relating to fuel flight planning
The operator’s procedures for domestic operations for planning minimum fuel requirements were based on Civil Aviation Advisory Publication (CAAP) 234-1 (1) Guidelines for Aircraft Fuel Requirements. Those procedures allowed for fuel remaining to be recalculated before an aircraft passed its diversion point to a suitable alternate aerodrome. If crews undertook this calculation they were then authorised to continue to their destination if sufficient fuel remained to meet all of the fuel requirements for the contemplated flight at that time.
Specifically, section 5.17.2 of the operations policy and administration manual, titled Fuel Requirements stated, in part that an aircraft may continue:
…to the destination aerodrome from the diversion point only after it has been determined that the fuel on board the aircraft at that point is sufficient, in accordance with the fuel requirements detailed above [allowing for the recalculation of fuel remaining], to enable to aircraft to complete the flight to that destination aerodrome.
The flight crew reported reviewing the forecast weather at the destination before take-off by obtaining the most recent trend forecast for Perth Airport.
Alternative landing options at Perth
AIP section ENR 1.5, 1.10 Missed Approach – Standard Procedures paragraph 1.10.1 listed the circumstances in which an instrument approach was to be discontinued and a missed approach carried out. In the case of a runway approach at Perth such as the runway 03 instrument landing system (ILS) approach, these included:
the pilot not having clear visibility of the runway threshold, or approach lighting or other markings identifiable with the runway
once an aircraft reached the decision altitude of 320 ft, a visibility of less than 1,500 m.
ILS approaches were also available for use on runways 21 and 24 at Perth. These approaches could be accomplished in slightly worse weather conditions than for a runway 03 ILS, with a minimum visibility requirement of 800 m once reaching the decision altitude of 250 ft and 260 ft respectively. Unlike runway 03, runways 21 and 24 were also equipped with high intensity approach lighting that would have helped the crew obtain visual reference with the runway.
It would have taken some time to manoeuvre to conduct an ILS approach to a different runway, and there were a number of aircraft in the vicinity also intending to land, which could have delayed any subsequent approaches. In the event, when the aircraft landed after discontinuing the missed approach, it was carrying about 30 minutes more fuel than the operator’s minimum planned fuel for arrival at Perth.
Operator’s missed approach criteria
A missed approach procedure is initiated by conducting a go-around. During a go-around a number of actions are coordinated by the flight crew to reconfigure the aircraft and its systems for a climb away from the airport. The operator’s operating procedures for this aircraft type stated:
A go around can be as a result of not being visual at the missed approach point of an instrument approach or if the approach is not stable or becomes destabilised.
and that:
Before committing to a further approach following a Missed Approach/Go Around, the crew must review the factors that led to the preceding Missed Approach/Go Around and ensure that those factors are alleviated in the subsequent approach.
Approach and landing Accident Reduction Tool Kit
The Flight Safety Foundation has developed a tool kit to help manage the risks of approach and landing accidents. The kit highlights that unstabilised approaches were a factor in a high proportion of approach and landing accidents,[10] and recommends the use of stabilised approach criteria to mitigate this risk.
The criteria for a stabilised approach promoted by the Flight Safety Foundation were the same as those specified in the company’s operational procedures. In respect of the risk of continuing an unstable approach, the operator’s procedures stated:
In order to provide maximum opportunity for a well executed landing to be completed, a consistent and stable approach path is necessary. Continuing to land from an unstable approach has been shown to be the precursor of many landing accidents.
The initiation of the missed approach procedure by the captain resulted in the aircraft being outside the operator’s parameters for a stabilised approach. Continuing the landing from this profile increased the risk to the aircraft during the landing sequence.
Previous occurrences
The following occurrences were investigated by the ATSB and are available for download at ATSB website. Together with the crew’s experience in this occurrence, each provides an example of the landing risks/threats associated with bad/deteriorating destination weather and its management.
On 16 September 2006 at 0038 Western Standard Time, an Airbus A330 landed on runway 21 at Perth Airport in weather conditions that were below the applicable landing minima. The aircraft, registered VH-QPJ, was being operated under the instrument flight rules on a scheduled passenger flight from Singapore to Perth.
Before departure from Singapore, the TAF for Perth Airport predicted a 30 per cent probability of fog after 0200. The aircraft was due at Perth at 0020 so, in accordance with the operator's fuel policy, fuel was not specifically carried for a diversion from Perth to an alternate aerodrome. While the aircraft was in cruise, the TAF was revised to forecast fog from 2400, but the TTFs that superseded the TAF trended fog from 0030.
At about 2350, when the flight crew commenced descent, the aircraft passed the point where it had sufficient fuel to divert to Learmonth, Western Australia. About 10 minutes later, the TTF was amended to forecast fog before the aircraft's arrival time. The fog occurred at about 0015. The crew attempted two ILS approaches before they used autoland to land on runway 21 in weather conditions that were below the prescribed landing minima for the ILS.
The aircraft was certificated to conduct an autoland and the flight crew held the necessary qualifications. However, the airport’s ILS facilities were not approved for autoland operations in low visibility conditions. At that time, there were no autoland capable airports in Australia.
On 23 September 1999, a Boeing 747 was landing in adverse weather conditions at Bangkok Airport, Thailand. Shortly before touchdown, a missed approach was initiated but the aircraft’s wheels contacted the runway. The missed approach procedure was then discontinued, with a lack of clarity between the flight crew. The sequence of control inputs by the crew meant that not all the available aircraft equipment and systems that might have assisted its deceleration on the runway were operating to their maximum efficiency. In this configuration, there was insufficient runway remaining to stop and the aircraft overran the runway.
From the evidence available, the following findings are made with respect to the weather-related operational event involving a Boeing 717, registered VH-NXO, which occurred at Perth Airport on 1 June 2012. These findings should not be read as apportioning blame or liability to any particular organisation or individual.
Contributing factors
The weather forecast for Perth Airport was amended to include the requirement to carry sufficient fuel to divert to a suitable alternate aerodrome when the aircraft no longer had that amount of fuel remaining.
The captain, as the flying pilot, continued an approach to land after the approach had been destabilised by initiating a go-around procedure.
Other factors that increased risk
The flight crew did not update the weather forecast for Perth Airport en route which, although in this instance did not indicate an operational requirement, was a missed opportunity to update pertinent operational information prior to the aircraft being committed to its destination.
Other findings
Given the circumstances, when confronted by a choice between completing the missed approach with an indeterminate outcome and landing from a discontinued missed approach, the captain chose the option that was considered to represent lower risk.
The operator’s procedures in the case of an unstabilised approach were unambiguous and reflected those promoted by the Flight Safety Foundation.
Safety analysis
Introduction
The flight proceeded normally until just after commencing descent to Perth Airport, when visibility reduced due to the rapid onset of fog. This deterioration in the weather conditions occurred after the last diversion point to a suitable alternate aerodrome for the flight and resulted in the crew being committed to landing the aircraft at Perth. The following analysis will consider the role of weather and procedural factors in this occurrence and assess the safety implications for future operations in similar conditions.
Weather factors
The aerodrome and trend forecasts for Perth Airport did not predict weather conditions that required the carriage of sufficient fuel to fly to a suitable alternate landing airport, until after the aircraft no longer had sufficient fuel to divert to a suitable alternate aerodrome. This committed the crew to landing at Perth where a safe landing could no longer be assured.
In the few minutes before landing, the flight crew observed a rapid deterioration in the weather conditions, and their observations were reinforced by information heard on the aircraft radio. The flight crew were confronted with rapidly deteriorating unforecast weather conditions, and uncertainty about how much further the weather might deteriorate.
Procedural factors
The crew updated their knowledge of the weather observations for Perth Airport as soon as the broadcast of those observations from the airport could be received. Observations with a trend forecast appended were available previously from the automatic en route information service facility at Meekatharra. However, the delay normally encountered by the captain in obtaining updated weather from this facility and the timing of this particular flight influenced the captain to not access that information in this case.
Weather observations do not predict expected weather conditions. In contrast, a weather forecast is intended to provide the best approximation of future weather conditions. Knowledge of any changes to forecast weather at the destination is assured when flight crews request or obtain the latest version of the relevant forecast. For safety purposes, the most relevant time to ensure that the destination’s forecast weather remains suitable for an assured landing is shortly before the aircraft no longer carries sufficient fuel to divert to an alternate aerodrome where a landing can be assured.
The crew had a reasonable knowledge of the point in the flight when they were committed to a landing in Perth because of the fuel remaining, and an amended forecast was not issued for Perth Airport before this time. However, by not confirming the latest weather forecast for Perth, and its potential effect on the flight, the crew could not assure themselves of the validity of that understanding.
Conduct of the approach and landing
The flight crew commenced the instrument landing system (ILS) approach to runway 03 and encountered unforecast and rapidly deteriorating weather, the extent and duration of which was unknown. Similar instrument approaches were available to runways 21 and 24 that allowed for landing in slightly worse weather conditions, but the time taken to change to either of these approaches would, given the traffic situation, have impacted further on the crew’s now less-than-ideal fuel situation.
In the event, the captain was confronted with a short-notice choice between completing the missed approach, with an indeterminate outcome, and landing from a discontinued missed approach. He was aware of the risk associated with continuing the landing in what amounted to an unstabilised configuration, but considered this option represented lower risk.
Sources and submissions
Sources of information
The sources of information during the investigation included the:
flight crew of VH-NXO
Cobham Airline Services (Cobham).
Submissions
Under Part 4, Division 2 (Investigation Reports), Section 26 of the Transport Safety Investigation Act 2003 (the Act), the Australian Transport Safety Bureau (ATSB) may provide a draft report, on a confidential basis, to any person whom the ATSB considers appropriate. Section 26 (1) (a) of the Act allows a person receiving a draft report to make submissions to the ATSB about the draft report.
A draft of this report was provided to the flight crew, Cobham and the Civil Aviation Safety Authority.
Submissions were received from the aircraft captain, first officer, Cobham and the Civil Aviation Safety Authority. The submissions were reviewed and where considered appropriate, the text of the report was amended accordingly.
The occurrence
On 1 June 2012 at 0027 Western Standard Time,[1] a Boeing 717 aircraft, registered VH-NXO and operated by Cobham Airline Services, landed from a runway 03 instrument landing system (ILS)[2] approach at Perth Airport, Western Australia. The flight crew had initiated a missed approach procedure, due to visual reference not being established at the decision altitude, but discontinued this procedure and landed after the pilot flying (PF)[3] saw the runway.
The previous evening, the aircraft was flown from Perth to Paraburdoo, Western Australia and the occurrence took place on the return flight to Perth. Shortly before departure from Paraburdoo for the 90-minute flight to Perth, the flight crew obtained a trend forecast (TTF)[4] for Perth. They reported assuring themselves that based on this forecast, there was no weather-related requirement to carry sufficient fuel to divert from Perth Airport to an alternate aerodrome.[5] The aircraft took off from Paraburdoo at 2255.
Despite the lack of a requirement to provide for an alternate for Perth, the aircraft was carrying sufficient fuel to allow for the flight to be diverted to Kalgoorlie until shortly after commencing descent into Perth. Beyond that time, the aircraft was no longer carrying sufficient fuel to divert to another suitable aerodrome.
During the flight, the flight crew did not seek or obtain an amended or updated forecast for Perth. The captain reported that he normally obtained the latest TTF for Perth when overflying the automatic en route information service (AERIS) at Meekatharra, about 360 NM (667 km) north-north-east of Perth. However, the timing of the flight and the delay normally encountered in updating the available weather information on the AERIS meant that he did not expect to obtain the latest TTF at that time. When the aircraft was about 240 NM (440 km) from Perth, the crew obtained the latest automatic terminal information service (ATIS)[6] weather observation for Perth, which provided no indication of deteriorating weather.
After the aircraft descended below 11,000 ft, air traffic control (ATC) notified the crew of deteriorating visibility at Perth Airport, and the first officer (FO) observed a thin layer of cloud between the airport and the coast. ATC notified the crew of continuing reducing visibility as they manoeuvred the aircraft for a runway 03 ILS approach. While manoeuvring the flight crew heard on the radio that another aircraft had conducted a missed approach procedure from this approach.
As the aircraft started the ILS approach, it flew through small patches of cloud until it descended below 1,000 ft, when it entered continuous cloud. At the decision altitude of 320 ft the FO, who was the pilot monitoring (PM) called ‘nil sighting’. That statement indicated that the FO had not obtained visual reference with the runway. The captain, who was the PF, called ‘going around’ and initiated a missed approach procedure by pressing the go-around switches and advancing the thrust levers. It was reported that the captain had not initiated the next actions for the missed approach procedure when the aircraft flew clear of cloud and both crew members obtained visual reference with the runway. The captain called ‘landing’, disconnected the autopilot and the autothrottle, and manually landed the aircraft without exceeding any flight or landing tolerances (Figure 1).
Figure1: Plot of selected aircraft parameters during the approach and landing
Source: ATSB
The captain later reported being concerned about the unforecast weather deterioration with limited fuel remaining, and not knowing if the weather would deteriorate further after going around and repositioning for a second attempted approach and landing. He reported that this concern influenced his decision to land after initiating the missed approach, during which the aircraft exceeded the operator’s stabilised approach criteria for a landing.
Purpose of safety investigations & publishing information
Purpose of safety investigations
The objective of a safety investigation is to enhance transport safety. This is done through:
identifying safety issues and facilitating safety action to address those issues
providing information about occurrences and their associated safety factors to facilitate learning within the transport industry.
It is not a function of the ATSB to apportion blame or provide a means for determining liability. At the same time, an investigation report must include factual material of sufficient weight to support the analysis and findings. At all times the ATSB endeavours to balance the use of material that could imply adverse comment with the need to properly explain what happened, and why, in a fair and unbiased manner. The ATSB does not investigate for the purpose of taking administrative, regulatory or criminal action.
Terminology
An explanation of terminology used in ATSB investigation reports is available here. This includes terms such as occurrence, contributing factor, other factor that increased risk, and safety issue.
Publishing information
Released in accordance with section 25 of the Transport Safety Investigation Act 2003
Ownership of intellectual property rights in this publication
Unless otherwise noted, copyright (and any other intellectual property rights, if any) in this report publication is owned by the Commonwealth of Australia.
Creative Commons licence
With the exception of the Coat of Arms, ATSB logo, and photos and graphics in which a third party holds copyright, this publication is licensed under a Creative Commons Attribution 3.0 Australia licence.
Creative Commons Attribution 3.0 Australia Licence is a standard form licence agreement that allows you to copy, distribute, transmit and adapt this publication provided that you attribute the work.
The ATSB’s preference is that you attribute this publication (and any material sourced from it) using the following wording: Source: Australian Transport Safety Bureau
Copyright in material obtained from other agencies, private individuals or organisations, belongs to those agencies, individuals or organisations. Where you wish to use their material, you will need to contact them directly.
At about 0930 Eastern Standard Time on 28 May 2012, the pilot of a Cessna Aircraft Company 172 aircraft, registered VH-WLF, departed Wentworth Airport, New South Wales for a private flight under the visual flight rules. No details of the flight were submitted to Air Traffic Services nor left with any other person and there was no requirement to do so. A property owner at the airport witnessed the aircraft depart and, following the failure of the aircraft to return to Wentworth, notified the police on the afternoon of 29 May 2012. As a result of that notification, a search was initiated.
Following an extensive visual search involving multiple aircraft, the crew of a search helicopter sighted the aircraft wreckage on the evening of 30 May 2012 near the Murray River, about 10 km west of Wentworth Airport. Upon landing, the helicopter crew established that the pilot had received fatal injuries.
What the ATSB found
The ATSB found that shortly after departure from Wentworth Airport the aircraft collided steeply with terrain at high speed and that the accident was not survivable. There was no evidence of any in-flight failure of the airframe structure or flight control system and the engine appeared to have been producing significant power at impact.
Based on advice from the aircraft manufacturer following their consideration of on-site evidence, and in the absence of an identified problem with the aircraft, the ATSB concluded that continual pilot input was probably applied to the flight controls immediately before the impact with terrain. However, the possibility that the pilot may have applied that input as a result of incapacitation could not be discounted.
Safety message
Although there was no requirement for details of the flight to be provided to Air Traffic Services or other agencies, the lack of such information hampered the search and rescue (SAR) response to this accident. If information on the intended flight route had been available, a more focussed search effort would have been possible and probably have resulted in the rapid location of the aircraft. In addition, although the carriage of a portable emergency locator transmitter (ELT) complied with the relevant regulations, a crash-activated ELT installation, normally associated with a permanent aircraft installation, would have expedited the provision to SAR agencies of more timely advice of an accident. Although earlier location of the aircraft would not have reduced the severity of the outcome in this instance, the availability of accurate flight information generally provides for a more timely emergency response.
On Saturday 7 April 2012 at around 1830 EST, an Airborne XT912 micro-light aircraft, registered 32-7581, impacted a tree and windmill approximately 2.2NM from Cootamundra airport. The force of the impact and subsequent fire fatally injured the two occupants.
Recreational Aviation Australia (RA-Aus) is assisting the New South Wales police service with their investigation of this occurrence. In response to a request for assistance from RA-Aus officers, and in accordance with the provisions of the Transport Safety Investigation Act (2003), the Australian Transport Safety Bureau initiated an External Investigation to facilitate the technical examination of an airspeed indicator instrument recovered from the accident aircraft.
Examination of the instrument has been completed and a report on the findings forwarded to RA-Aus on 4 September 2012.
At 1314:47 hours the pilot reported that he was ready to descend
and was cleared by Cairns ATC to "descend to 4000 feet, not below
DME steps". He was requested to report approaching 4000 feet on
descent and to advise his in-flight conditions at that time. The
pilot read back "four thousand, not below DME steps" and ATC
requested him to confirm that the aircraft's DME had "locked on"
again. The pilot replied "affirmative and indicating four niner
DME".
At 1326:21 hours Cairns ATC requested the pilot to report DME
distance, but there was no reply. Further attempts to establish
radio contact with the aircraft were unsuccessful. Search and
Rescue action was initiated and at 1625 hours a ground party
reported finding the wreckage of the aircraft on the southeastern
side of Mt. Bellenden Ker.
Examination of the wreckage did not reveal any evidence of
unserviceability or malfunction of the aircraft which might have
contributed to the accident.
Occurrence summary
Investigation number
197800033
Occurrence date
07/07/1978
Location
Mt Bellenden Ker, 47 Km South-south-east of Cairns
On 22 May 2012 at 1608 Eastern Standard Time, a Piper PA-34-220T, registered VH-PWQ (PWQ), conducting training under Instrument Flight Rules (IFR) and a Cessna R182, registered VH-JYG (JYG), on a pipeline survey under Visual Flight Rules (VFR) passed within 0.1 NM and 100 ft of each other in Class D airspace at Avalon aerodrome, Victoria.
The air traffic controller had provided traffic information to both aircraft, but the pilot of PWQ stated that the information was not sufficient for him to understand the intended track of JYG.
Traffic information provided by air traffic controllers must be concise, however it needs to include enough relevant reference information to enable the pilot to determine if any avoidance action is required. A recent amendment to documents used by air traffic controllers provided more detail on the provision of safety alerts in all classes of airspace and on when to issue avoiding action within surveillance coverage.
In Class D, where separation is not provided between IFR and VFR aircraft, pilots need to be aware of the limitations of the see-and-avoid principle. Pilots should also be aware of their responsibilities in Class D and conscious of the dangers of expectation.
On 25 May 2012, freight train 3PW4 collided with a motor vehicle (Toyota Corolla) that was fouling the railway track at the Cherry Street level crossing in Werribee, Victoria. The passenger in the Corolla died as a result of the collision and the driver was injured and required treatment in hospital.
What the ATSB found
The ATSB found that the driver of the Corolla had entered the level crossing when traffic was flowing relatively freely. Shortly after the Corolla entered the crossing, the lights, bells and boom barriers protecting the crossing began to operate for the approach of train 3PW4. Unbeknown to the Corolla driver, another vehicle had broken down just beyond the crossing. This led to her having to stop the Corolla in a position which was foul of the railway track.
When the crew of train 3PW4 saw the Corolla fouling the track, they made an emergency brake application. However, the train could not be stopped in time to prevent the collision.
The ATSB’s investigation found that the level crossing signage and road markings were generally in accordance with the applicable Australian Standards and that the crossing warning lights, bells and boom barriers had operated correctly.
The ATSB also found that while the collision was a direct result of the Corolla being in a position foul of the approaching train, the safety issues involved were more complex and extensive. The investigation identified several opportunities to enhance the safety of the existing grade crossing including changes to the road design, the provision of short-range warning lights, improving the coordination of the crossing protection system with the nearby pedestrian traffic lights, reducing the length of the crossing and the provision of suitable refuge/escape area(s).
What's been done as a result
Metro Trains Melbourne has advised that they will investigate the potential benefits gained from fitting short range lights at this and other similar level crossings. They have also advised that the options available for shortening the level crossing length will be explored in consultation with the Wyndham City Council.
The Wyndham City Council has advised that actions have been taken to improve the coordination of the nearby pedestrian crossing lights and that further coordination improvements are being considered. Council officers are also investigating ways to provide escape/refuge areas.
Safety message
Although the road rules (Victorian Road Safety Act 2009) make motorists primarily responsible for avoiding a collision with a train when negotiating a level crossing, prudent road and level crossing design is essential in helping to mitigate the risk of road and rail vehicles colliding.
Where it is feasible, road and rail authorities should consider additional measures to enhance the situational awareness of motorists negotiating level crossings and to address the risks associated with traffic queuing.
It is also imperative that motorists approaching level crossings are extremely vigilant.
On 17 May 2012, the flight crew of a de Havilland Canada Dash 8 aircraft, registered VH-XFZ and operated by Skippers Aviation Pty Ltd, was conducting a circling approach to runway 07 at Laverton Aerodrome, Western Australia. In conditions of low cloud, the crew positioned the aircraft on a close base leg to maintain visual reference with the runway threshold. This led to a steep final approach and a high rate of descent that triggered alerts from the aircraft’s Enhanced Ground Proximity Warning System (EGPWS) and exceeded the operator’s stable approach criteria. The crew heard some alerts from the EGPWS and knew they had a high rate of descent but at the time did not identify an unstable approach. The crew continued the approach and landed.
What the ATSB found
The ATSB found that at the time of the occurrence the flight crew did not have an adequate understanding of operational aspects of the aircraft’s EGPWS and the operator’s standard operating procedures in regard to mandatory go-arounds. Crew fixation on the runway environment at a time of higher than normal cognitive workload and an inadequate monitoring of the aircraft’s rate of descent resulted in the continuation of an unstable approach, contrary to the operator’s procedures. The ATSB also determined that the operator’s minimum height for achieving the criteria for a stable approach was lower than recommended by the International Civil Aviation Organization.
What has been done as a result
In response to this occurrence, the operator implemented a number of safety actions to refine their stabilised approach criteria and formulate a method of incorporating realistic EGPWS warning events in the Dash 8 simulator training program. The intent was to enhance crews’ ability to recognise and respond correctly and rapidly to EGPWS alerts.
Safety message
The ATSB continues to stress the risks associated with the handling of an approach to land. The Flight Safety Foundation cites a lack of go-arounds from unstable approaches as the number one risk factor in approach and landing accidents and the primary cause of runway excursions. This occurrence highlights the importance of crews adhering to standard operating procedures and correctly responding to cockpit warnings.
Occurrence summary
Investigation number
AO-2012-070
Occurrence date
17/05/2012
Location
Laverton Aerodrome
State
Western Australia
Report release date
05/12/2013
Report status
Final
Investigation level
Systemic
Investigation type
Occurrence Investigation
Investigation status
Completed
Mode of transport
Aviation
Aviation occurrence category
Unstable approach
Occurrence class
Incident
Highest injury level
None
Aircraft details
Manufacturer
De Havilland Canada/De Havilland Aircraft of Canada
