The investigation

The occurrence

On the afternoon of 12 May 2023, an instructor and student pilot in a Magni M16C Tandem Trainer gyroplane, registered G1850 and operated by Airborne Flight Training, were planning to conduct wheel balance training exercises (see the section titled Operational information) at Lake Macquarie Airport, New South Wales. The airport was located within class G, non‑controlled airspace and had a designated common traffic advisory frequency (CTAF) on which pilots made positional broadcasts to coordinate aircraft separation.

At about 1537, the student and instructor pilots, seated in the front and rear seats respectively, taxied the gyroplane onto the runway near the runway 25[1] threshold and then backtracked[2] towards the runway 07 threshold (Figure 1) to commence the wheel balance training. The training exercise involved the student accelerating the gyroplane on the runway while balancing on the main landing gear until the gyroplane lifted off the ground briefly. The student then handed control to the instructor who would land on the runway, turn the gyroplane around and backtrack towards the 07 threshold before handing control back to the student and repeating the exercise.

At about 1542, the student pilot reported making a ‘rolling' radio call on the CTAF to indicate they were commencing the first wheel balance exercise. About 30 seconds later, after accelerating along the runway and briefly becoming airborne, the gyroplane landed about half-way down runway 07 and turned around. During this turn, the student reported making another radio call to indicate they were backtracking towards the runway 07 threshold.

At about 1543, the pilot of an Extra EA 300L, registered VH-IOG and operated by Inverted Downunder, walked towards the aircraft, which was located on the airport apron near the eastern end of the runway, to prepare for a scenic flight with one passenger. This was to be the pilot’s fifth flight of the day in the Extra.

Figure 1: Lake Macquarie Airport showing G1850 estimated ground track and VH-IOG location

G1850 track estimated using CCTV footage and pilot statements. VH-IOG location based on CCTV footage.

Source: Google Earth, annotated by ATSB

At about 1544, the gyroplane’s student pilot commenced a second wheel balance exercise from the runway 07 threshold. While the gyroplane was undertaking this exercise, airport video footage showed that the pilot of the Extra stepped onto the parked aircraft’s wing to prepare the front seat for the passenger. By about 1545, the gyroplane had travelled towards the end of runway 07, adjacent to the apron area and was slowing down to turn around (Figure 2). The student recalled that during the turn, a backtracking radio call was made. At about the same time, the video footage showed the Extra’s pilot, who was still on the wing, appear to look up for about a second toward the gyroplane. Shortly after, the passenger climbed into the front seat of the Extra, while the gyroplane backtracked towards the runway 07 threshold.

Over the next 8 minutes, the Extra’s pilot secured the passenger in their seat, provided a pre-flight briefing, and then climbed into the rear seat, putting their seatbelt and helmet on. During this time, the instructor and student pilot performed a further 4 wheel balance exercises, with the gyroplane turning around at different locations along the runway (Figure 2), but none as far as during the second wheel balance exercise (near the airport apron). The student pilot and instructor recalled radio calls being made prior to the commencement of, and during the turnaround at the end of, each wheel balance exercise.

Figure 2: G1850 turnaround locations

Source: Google Earth, annotated by ATSB

At 1554:05, a few seconds after turning around following the sixth wheel balance exercise, the Extra’s pilot started the aircraft’s engine and conducted pre-flight checks which included switching on the aircraft’s radios.

At 1554:39, the Extra’s pilot began to taxi towards the runway while the gyroplane was backtracking along runway 07. At about 1554:53, the Extra’s pilot reported making a radio call on the CTAF that the aircraft was taxiing for runway 07.

At about 1555:09, and for about the next 10 seconds while taxiing, the Extra pilot reported visually looking for aircraft on final approach for runways 25 and 07, and for aircraft on the runway. The pilot recalled that most of their attention during this visual lookout was towards the ‘bad lighting’ at the runway 07 threshold and they recalled not seeing any aircraft. During this time, the Extra pilot made another radio call advising they were entering and backtracking runway 07. Shortly after, the aircraft crossed the hold point line without stopping and turned left onto the runway (Figure 3). The pilot stated that they did not usually stop at this line because they had unobstructed views towards the runway 07 threshold and final approach to runway 25 before this point. At a similar time, the student commenced the seventh wheel balance exercise from the runway 07 threshold. Both gyroplane pilots recalled that they did not see any aircraft on the runway at this time, nor  could they recall making a ‘rolling’ radio call prior to this exercise.

As the Extra backtracked runway 07, the student was accelerating the gyroplane along the runway. About 30 seconds later, as the gyroplane approached the midpoint of the runway, the instructor and student observed the Extra about 20 m ahead and backtracking towards them. The instructor took control and banked the gyroplane right to avoid a collision. The rotor blades impacted the runway surface before the gyroplane veered off the runway and collided with terrain, coming to rest on its side. The gyroplane sustained substantial damage to the rotor blades, propeller blades, and landing gear. The instructor was seriously injured, with the student sustaining minor injuries. The Extra pilot saw the gyroplane veer off the runway to the left, stopped their aircraft and exited to provide assistance. The Extra was not damaged and its occupants were uninjured.

Figure 3: G1850 and VH-IOG ground tracks before accident

Labels ‘A’ and ‘B’ are timestamps for the approximate locations of each aircraft.

Source: Google Earth, annotated by ATSB

Context

Pilot information

G1850 pilots

The instructor pilot held an Australian Sport Rotorcraft Association (ASRA)[3] pilot certificate and was approved by ASRA as a chief flying instructor (CFI). They had accrued 2,254 hours of flying time in gyroplanes and about 751 hours on the Magni M16 and Magni M16C Tandem Trainer gyroplane, with 43 of those hours flown in the previous 90 days.

The student held an ASRA pilot certificate and a Private Pilot Licence (aeroplane). The student had accrued about 330 hours of flying time in aeroplanes, and 60 hours in gyroplanes, 10 of which were on the Magni M16C Tandem Trainer gyroplane in the previous 90 days.

VH-IOG

The Extra pilot held a Civil Aviation Safety Authority (CASA) Commercial Pilot Licence (Aeroplane). They had accrued 7,800 hours of flying time, with about 600 hours on the Extra EA 300L, of which 18.5 hours were flown within the previous 90 days.

Aircraft information

G1850

The Magni M16C Tandem Trainer is a 2-seat gyroplane with fixed tricycle landing gear (Figure 4). A 4‑cylinder piston engine drives a 3-bladed pusher propeller, with an unpowered rotor to develop lift. The gyroplane has a pre-rotation system linking the engine to the rotor which, when engaged, can drive the rotor to start it spinning without needing forward motion.

The Magni M16C is 4.7 m long, 2.7 m high (fuselage about 1.5 m high), and 1.8 m wide, with a rotor diameter of about 8.5 m. An external landing light was fitted to the front of the fuselage with strobe lights fitted to each side of the fuselage and one on the rear of the mast.

The front seat was instrumented for the pilot in command and was occupied by the student. The rear seat was not fitted with instrumentation but had flight controls, and was slightly higher than the front seat to improve forward visibility. Both seats were fitted with 4-point harnesses and both pilots were wearing them at the time of the accident.

Figure 4: G1850

Source: Airborne Flight Training

VH-IOG

The Extra EA 300L is a low-wing, 2-seat aerobatic monoplane with fixed tailwheel landing gear and the rear seat was instrumented for the pilot in command. A 6-cylinder piston engine drives a 3-bladed tractor propeller. VH-IOG was manufactured in Germany in 1999 and first registered in Australia in June 2005 (Figure 5).

The aircraft is about 7 m in length and 1.8 m high while on the ground with a wheel track of 1.8 m and a wingspan of 8 m. External navigation and strobe lights were fitted to the wingtips.

Figure 5: VH-IOG

Source: Inverted Downunder

Operational information

The gyroplane instructor planned for the student to perform several wheel balance exercises to teach the student the correct pitch attitude for take-off, and the exercise included many similar aspects of a normal take-off. The United States Federal Aviation Administration (FAA) Rotorcraft Flying Handbook[4] described a normal gyroplane take-off as follows:

The instructor stated that if the student obtained the correct pitch attitude, the gyro would lift‑off briefly, before the instructor would take control and land on the runway, turn around, backtrack towards the runway 07 threshold, and repeat.

The instructor also stated that during the acceleration phase of the wheel balance exercise, the workload was high due to the multi-tasking required in monitoring the gyroplane’s attitude, the student’s flight control inputs, and the gyroplane’s response.

The student stated that during the acceleration phase of each wheel balance exercise, they glanced down occasionally to look at the cockpit instrumentation, but their focus was primarily on looking out of the aircraft and monitoring the gyroplane’s pitch attitude.

Meteorological information

The weather at Lake Macquarie Airport at the time of the accident was good with a light easterly wind, visibility greater than 10 km, and no cloud over the airport.

At the time the Extra’s pilot was taxiing towards the runway from the apron (heading north), the sun was positioned at about the 10 o’clock (300°) position,[5] at an elevation of about 12°. This would have placed the sun in the pilot’s field of view while looking towards the runway 07 threshold (Figure 6). It is likely that the gyroplane would have been illuminated by the sun at this time. The Extra pilot stated that as there was a light wind, a take-off from runway 07 was preferable since the sun was getting low in the west making it difficult to look in that direction. The pilot stated that they were wearing a tinted helmet visor, which would have reduced sun glare.

Figure 6: VH-IOG turning left to backtrack runway 07

Source: Airport operator

While the gyroplane was accelerating towards the Extra on runway 07 during the seventh and final wheel balance exercise, the sun was positioned behind the gyroplane at about the 8 o’clock position. The Extra was likely illuminated by the sun while backtracking along the runway towards the gyroplane.

Airport information and procedures

Lake Macquarie Airport was an aircraft landing area,[6] located about 20 km southwest of Newcastle, New South Wales. It had an elevation of 5 ft above mean sea level, and a single, sealed 880 m long and 11 m wide runway designated 07/25, with trees lining each side.

As a non-controlled airport, separation between aircraft was maintained by ‘alerted see-and-avoid’ principles guided by Civil Aviation Safety Authority (CASA) advisory circulars[7]. Unalerted see‑and‑avoid relies on a pilot or crew visually detecting other aircraft without the assistance of other aids or information. This visual detection can be improved through pilots being alerted to an aircraft’s presence by radio, electronic systems, or other means (alerted see‑and-avoid).

At Lake Macquarie Airport, the carriage and use of a radio was required by the airport operator for all operating aircraft. Pilots were required to broadcast their position and intention so that nearby traffic would have an awareness of their aircraft and be able to plan or act accordingly.

All 3 pilots were familiar with the airport operations and had operated at Lake Macquarie for many years. Both aircraft were on the correct CTAF frequency before the accident, with all pilots having 2-way communications with other aircraft. None of the pilots reported hearing the other aircraft’s radio calls. The gyroplane pilots could not recall whether they had made a rolling call at the start of the final wheel balance exercise.

The Extra pilot reported that once they had taxied clear of the apron toward the hold point line, there was nothing obstructing their view of the runway 07 threshold other than the lighting conditions. The gyroplane instructor similarly reported no limitations with visibility of the entire runway when viewed from the runway 07 threshold.

The Extra pilot stated that there had been historically poor radio usage at the airport, and that they needed to use visual lookout ‘aggressively’ and not rely on radio communications. The gyroplane instructor considered radio to be a secondary means of collision avoidance to visual lookout.

Limitations of see-and-avoid

The see-and-avoid principle has been an effective defence in preventing aircraft collisions, but has several limitations (ATSB, 1991).

Workload

See-and-avoid can only be effective when the pilot is looking outside the cockpit. However, many tasks require pilots to direct their attention inside the aircraft, particularly when conducting operations and tasks that involve a high workload.

There was an opportunity for the Extra pilot to become aware of the gyroplane while they were on the Extra’s wing preparing the passenger’s seat, when they looked up briefly toward the gyroplane turning around on the runway. However, the Extra’s pilot recalled being unaware of any other operations being conducted at the airport while on the apron preparing the passenger for the flight. It is possible that the pilot’s focus on preparing the aircraft and passenger for flight resulted in them not detecting the gyroplane despite appearing to look towards it.

Although the Extra had occupied the runway for about 30 seconds before the gyroplane pilots saw the aircraft, the gyroplane pilots’ focus on other traffic in the runway environment was probably limited due to the complex training exercise being conducted. The instructor and student’s attention was primarily focused on the gyroplane’s motion and attitude to ensure the exercise was being conducted appropriately.

Visual search

In daylight, a pilot must look almost directly at an object to see it and it is possible for a pilot to look past an object if they do not see it directly. An FAA advisory circular recommended scanning the entire visual field outside the cockpit with eye movements of 10 degrees or less, with about a second spent on each 10 degree sector, to ensure effective detection of conflicting traffic.[8]  

It was estimated that the Extra pilot would have spent about 10 seconds on their visual lookout which included viewing both ends of the runway and associated approaches. While the Extra’s pilot was approaching the runway from the apron, the runway 07 environment would have been captured in a sector about 30 degrees horizontal by 10 degrees vertical. This suggests that the Extra pilot would have required at least 3 seconds for an effective visual scan of the runway (without accounting for any other factors). While the pilot probably spent at least that length of time viewing the runway 07 environment, there were other factors that likely affected their visual scan and their ability to detect the gyroplane in that time.

Cockpit visibility

Items such as window pillars, sun visors, and front seat occupants may impact on the pilot’s ability to see an aircraft. The FAA Airplane Flying Handbook[9] described the reduced forward visibility of tailwheel aircraft:

The pilot reported that the Extra EA 300L had limited visibility from inside the cockpit between 11‑1 o’clock directions while on the ground. Their usual procedure at Lake Macquarie Airport was to undertake a ‘zig-zag’ manoeuvre at the half-way point of the runway to allow them to see the runway environment and ensure the final approach was clear of traffic. The manoeuvre was only performed once as the narrow runway required the aircraft to slow down significantly. On this occasion, the accident occurred before the Extra had reached the half-way point on the runway.

Threshold for acuity

The eye’s ability to recognise an object also depends on the relative size of the object and an approaching aircraft might be too small to be seen. Studies have estimated the size an object needs to be for it to be sighted, with estimations of visual angle varying from about 0.02° to detect features of an alphabet letter (Howett, 1983), to at least 0.2° (NTSB, 1988) to reasonably detect an overall object. However, visual acuity varies widely across the retina of the eye and therefore, these values are only of relevance when looking directly at an object. Additionally, these observations were conducted under certain conditions, for example high object contrast with the background and moderate illumination (Howett, 1983), while the particular conditions experienced by the pilots involved in this occurrence were likely different.

With the Extra’s pilot at the hold point line and the gyroplane at the runway 07 threshold lined up with the runway, the estimated angular size of the gyroplane’s fuselage including landing gear would have been between 0.11° (height) and 0.14° (width). If the gyroplane pilots were at the runway 07 threshold and looked towards the runway 25 end with the Extra facing them on the runway, the estimated angular size of the Extra’s fuselage would have been about 0.14° (height and width). While the angular size of the Extra’s wingspan and the gyroplane’s rotor would be larger, these were both thin making them difficult to detect at such a distance compared to each aircraft’s fuselage.

Background features

Detecting an aircraft can become more difficult against a complex background that has different colours, contours, and objects. Aircraft are more easily spotted if they have a high contrast with their background. Images taken from around the midpoint on the runway about 20 minutes after the accident (Figure 7) provided some indication of the background features present at the time of the accident:

• The background behind the runway 07 threshold end had some small dark areas of shrub where the gyroplane’s white fuselage illuminated by the sun would have provided good contrast. However, the fuselage and background area covered by the shrub were small, and the light blue of the lake, and lighter terrain areas covered with haze in the distance, would have a presented a lower contrast difference with the white fuselage.
• Behind the runway 25 threshold was a highway at the same elevation as the runway, which video footage showed was busy with traffic around the time of the occurrence, with trees illuminated by the sun behind the highway. Although the Extra’s yellow nose and spinner would have been illuminated by the sun during the wheel balance exercise, the background behind the Extra had the sideways motion of traffic at the same level as the Extra creating a more complex scene. In addition, the trees in the background were also illuminated by the sun potentially reducing the contrast of the nose and spinner as the Extra moved closer to the gyroplane.

Figure 7: background features at runway ends

Source: Inverted Downunder

Other factors affecting visibility

In regard to aircraft lighting, research has shown that lights are generally ineffective in daylight at making an aircraft more visible, especially against bright sky backgrounds and can be less conspicuous than the aircraft itself, but may make aircraft more visible against terrain or in conditions of low light.  The Extra’s strobe lights were off while the aircraft was backtracking runway 07. The gyroplane strobe lights were on at the time of the accident and the landing light was off.

Glare occurs when unwanted light enters the eye. Glare can come directly from the light source or can take the form of veiling glare, reflected from crazing or dirt on the windscreen. The Extra’s pilot reported that the cockpit canopy was cleaned between flights and had some scratches as it was the original canopy fitted from manufacture. Although the pilot was wearing a sun visor to reduce glare, the sun would have been in the pilot’s field of view while looking towards the runway 07 threshold before entering the runway. The associated glare, which may have been exacerbated by the cockpit canopy, would have probably reduced the pilot’s ability to detect the gyroplane.

Additionally, it is difficult to see another aircraft when there is little relative motion between one aircraft and the other, such as when they are moving towards the same location in space. There was little relative movement between the 2 aircraft while (a) the gyroplane pilots were accelerating towards the backtracking Extra and (b) the gyroplane was positioned near the runway 07 threshold while the Extra pilot was visually looking towards that location before turning onto the runway.

Recorded data

Airport video footage from several locations captured the Extra pilot’s pre-flight activities, taxi, and backtrack towards the runway 07 threshold. The footage also showed segments of the gyroplane’s wheel balance exercises when in view from around the middle of the runway towards the runway 25 threshold. Footage of the runway 07 threshold up to the runway midpoint was not captured by any available video camera.

CTAF radio broadcasts were not recorded at Lake Macquarie Airport. Of the airports that operated on the same CTAF, Warnervale Airport (28 km south-west of Lake Macquarie Airport) was the only airport that recorded radio transmissions. Due to distance and line-of-sight limitations, radio calls on or near the ground at Lake Macquarie were not normally received at Warnervale Airport. The ATSB reviewed recorded radio calls from Warnervale while both the Extra and gyroplane were operating at Lake Macquarie Airport, however, no radio calls from either aircraft were recorded. No recorded data was available from either aircraft.

Safety analysis

Radio alerting

The gyroplane student pilot recalled making backtracking radio calls when turning around at the end of every wheel balancing exercise. However, the final backtracking call was made before the Extra pilot had turned the aircraft’s radio on, and therefore, they would not have heard this radio call. Additionally, the gyroplane pilots could not recall making a rolling call at the commencement of the final wheel balancing exercise prior to the accident, and there were no other sources of evidence to assist in establishing whether this call was made. In any event, the Extra pilot reported that they did not hear any call.

The Extra pilot reported making 2 radio calls before entering the runway. However, for reasons that could not be determined, the gyroplane pilots reported that they did not hear these calls. Consequently, neither aircraft’s pilots were alerted to the other’s presence over the radio and therefore, aircraft separation became solely reliant on each aircraft’s pilots seeing each other.

Visual search

The gyroplane was operating on the runway for about 11 minutes while the Extra pilot was on the apron preparing for the flight. During this time, the gyroplane was primarily on an area of the runway some distance from the pilot and not directly in sight, limiting the Extra pilot’s ability to detect it during this time.

The Extra pilot did not sight the gyroplane before entering the runway. The gyroplane pilots also did not sight the Extra at the start of their seventh and final wheel balance exercise, or while accelerating on the runway until a collision was imminent. While the reasons for this could not be determined, there were likely many common factors that reduced the ability of the pilots to identify each other such as the small angular size of each aircraft, the complex and cluttered background with reduced contrast difference, and the minimal relative movement between each aircraft.

The effectiveness of the Extra pilot’s visual scan was likely also affected by sun glare before entering the runway, and the tailwheel configuration of the aircraft which limited forward visibility while backtracking. The gyroplane pilots were likely also influenced by the higher workload associated with the training exercise, which probably reduced their available attention for identifying conflicting aircraft.

Findings

From the evidence available, the following findings are made with respect to the collision with terrain involving Magni M16C Tandem Trainer gyroplane, G1850, while avoiding Extra EA 300L, VH‑IOG.

Contributing factors

• Before entering the runway, the pilot of VH-IOG did not see G1850 occupying the runway and subsequently backtracked towards G1850. As VH-IOG was a tailwheel aircraft, the pilot was unable to sight G1850 while backtracking.
• While accelerating on the runway, the instructor and student in G1850 did not see VH-IOG backtracking towards them until a collision was imminent. While manoeuvring to avoid a collision, G1850 collided with terrain.

Safety actions

Safety action by Lake Macquarie Airport

In May 2023, the airport operator released a bulletin reminding all operators based at Lake Macquarie Airport of several aspects of safe operational practice highlighted by this event, including that:

• aircraft should stop forward motion at the hold point line (or equivalent for helicopters) to ensure a good lookout prior to entering the runway environment
• pilots are to ensure they know and use correct radio terminology while operating at the airport and to broadcast their intentions
• although radio discipline was required, it cannot be relied upon for safety, and that the visual lookout was paramount
• for operations involving a backtrack for runway 07, aircraft should turn through 90° in the turning node at the far end, stop to lookout, then broadcast a radio call on lining up
• the runway should only be occupied for the minimum time required to either taxi, take off, or land.

The airport operator also advised that:

• the hold point line at the apron end of the runway (near the runway 25 threshold) had been repainted and a hold line also painted at the runway 07 end
• CTAF radio recording equipment was purchased and anticipated to be installed in February 2024. This will ensure all communications can be reviewed periodically, and in the event of an incident.

Safety action by Inverted Downunder

The operator of VH-IOG advised the ATSB that operational procedures were updated to include requirements for:

• a ground employee to have a hand-held radio, switched on and in reach for all operations, and to monitor any departure and arrival radio calls
• pilots to stop at the hold point before entering the runway for departures.

Safety action by Australian Sport Rotorcraft Association

The Australian Sport Rotorcraft Association (ASRA) advised the ATSB that, in response to this accident and other previous sport rotorcraft accidents, ASRA intends to replace the one-off human factors exam, which is completed as a requirement of the ASRA pilot certificate, with an updated exam to be completed recurrently as part of each biennial flight review.

Sources and submissions

Sources of information

The sources of information during the investigation included the:

• pilot and passenger of the VH-IOG
• instructor and student of G1850
• VH-IOG operator photos
• New South Wales Police Force photos
• CCTV footage from Lake Macquarie Airport and Westpac Rescue Helicopter Service

References

Australian Transport Safety Bureau (1991),

CASA (Civil Aviation Safety Authority (2021), Operations in the vicinity of non-controlled aerodromes, AC 91-10v1.1.

CASA (Civil Aviation Safety Authority (2021), Pilots' responsibility for collision avoidance, AC 91‑14v1.0.

FAA (Federal Aviation Administration) (2021), Airplane Flying Handbook, FAA-H-8083-3C, United States.

FAA (Federal Aviation Administration) (2000), Rotorcraft Flying Handbook, FAA-H-8083-21, United States.

FAA (Federal Aviation Administration) (2022), Pilots’ Role in Collision Avoidance, Advisory Circular 90-48E, United States.

Howett, G. L. (1983), Size of letters required for visibility as a function of viewing distance and observer visual acuity (National Bureau of Standards Technical Note 1180).

National Transport Safety Board (1988), Aircraft Accident Report - Midair Collision of Skywest airlines Swearingen Metro II, N163SW, and Mooney M20, N6485U, Kearns, Utah, January 15, 1987.

Submissions

Under section 26 of the Transport Safety Investigation Act 2003, the ATSB may provide a draft report, on a confidential basis, to any person whom the ATSB considers appropriate. That section 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 following directly involved parties:

• Pilot of VH-IOG
• instructor and student of G1850
• operators of VH-IOG and G1850
• Lake Macquarie Airport
• the Australian Sport Rotorcraft Association (ASRA)
• the Civil Aviation Safety Authority (CASA).

Submissions were received from:

• instructor and student of G1850
• operator of G1850.

The submissions were reviewed and, where considered appropriate, the text of the report was amended accordingly.

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 Published by: Australian Transport Safety Bureau © Commonwealth of Australia 2024 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.

The occurrence

On 7 May 2023, a pilot of a Diamond Aircraft Industries Inc. DA 40, registered VH-ERE (ERE) and operated by Flight Training Adelaide, was conducting a solo training flight from Sunshine Coast Airport, Queensland to Brisbane West Wellcamp Airport, Queensland.

At 1322 local time, while parked at the general aviation area on the airport, the pilot contacted air traffic control (ATC) requesting a departure to the south‑west. ATC instructed the pilot to ‘taxi via Foxtrot to holding point[2] Foxtrot runway 31’[3] (Figure 1) and cleared them to depart for Wellcamp via Esk at 4,500 ft. The pilot readback ‘taxi via Foxtrot, use runway 31 and cleared to Esk at 4,500’. ATC reiterated ‘taxi to holding point Foxtrot’ to which the pilot apologised after reading back ‘taxi to holding point Foxtrot’.

Figure 1: VH-ERE taxi path

Source: Google Earth annotated by the ATSB

ATC then turned their attention to a Boeing 737 (737), which was on final for runway 31, and an airport safety car that was escorting an aircraft under tow to the general aviation parking area. At 1327:25, while the 737 was on final approach, ATC cleared it to land on runway 31.

At 1327:40, ERE stopped at holding point Foxtrot and 20 seconds later the pilot radioed ATC and advised ‘holding short of Foxtrot’. ATC observed ERE stationary at the holding point and instructed the pilot to ‘hold short runway 31’ to which the pilot responded ‘Wilco’. ATC then requested a specific readback of the instruction to hold short runway 31 however, the pilot did not respond. Following a second request from ATC, the pilot responded with ‘Hold short runway 31’.

Ten seconds later, while ATC was completing a departure clearance for another aircraft on the ground and updating flight progress strips,[4] ERE proceeded to cross the holding point without a clearance. The pilot later advised misunderstanding the instruction to hold short of runway 31 as they thought they were holding short of taxiway Foxtrot and that there was a second holding point closer to the runway. The driver of the safety car, who could see ERE and had heard the exchange between the pilot and ATC, notified ATC that ERE had ‘gone onto the runway’ as soon as there was a break on the radio. ERE had travelled approximately 74 m in this time.

Figure 2: Location of VH-ERE to inbound aircraft

Source: Sunshine Coast Airport annotated by the ATSB

The controller immediately instructed the 737, which was now on late final about 250 ft above the runway, to conduct a go around. One second after the go around instruction was given, ERE stopped. The pilot advised that as they were nearing the intersection with the runway and after hearing ATC instruct the approaching aircraft to go around, they stopped as they could not see a second holding point. The crew of the 737 advised that they had seen ERE stationary at holding point Foxtrot, however due to the high nose attitude of the aircraft, they lost sight of it under the aircraft’s nose as they continued the approach.

At 1329, ATC advised the 737 to make a left circuit and 20 seconds later instructed ERE to make a right turn and vacate the runway at Foxtrot. The pilot turned the aircraft around and taxied back on taxiway Foxtrot and after passing the holding point, was instructed by ATC to turn around and hold position. The 737 landed on runway 31 uneventfully 6 minutes later.

At 1337, ATC advised ERE to taxi ahead and hold short of runway 31 on Foxtrot. The pilot taxied on Foxtrot and just prior to reaching the holding point, ATC advised the pilot that they were at the holding point and described the markings.

At 1341, ATC instructed ERE to line up on runway 31, however, before they entered the runway ATC confirmed with the pilot that they were okay to continue the flight, to which the pilot replied, ‘all good’. ATC then cleared ERE for take-off and the pilot conducted an uneventful take-off and flight to Brisbane West Wellcamp Airport.

Context

Pilot

The pilot held a student pilot licence. They commenced training on 12 September 2022 at Brisbane West Wellcamp Airport. At the time of the occurrence, they had a total flying experience of 132.5 hours, of which 33.7 hours had been in the previous 30 days.

Runway and taxiway information

In June 2020, stage 1 construction of a new runway was completed and officially handed over to the Sunshine Coast Airport for operation. Stage 2, which included the completion of the displaced threshold, was completed in December 2020. The runway has an orientation of 128 degrees/308 degrees magnetic, giving the runway its 13/31 designation. The runway length is 2,800 m, which includes a 175 m permanently displaced threshold for runway 31 and a 170 m starter extension.[5] The airport operates within Class D airspace.

Taxiway Foxtrot is the repurposed southern end of the decommissioned runway 18/36. Due to the angle between the taxiway and runway 31 (approximately 130⁰ - Figure 3), there is approximately 140 m of taxiway from holding point Foxtrot to the intersection with runway 31 required to ensure that the holding point remained outside of the runway strip. Once reaching the intersection, there is approximately 350 m to the displaced runway threshold.

Figure 3: Taxiway Foxtrot in relation to the runway and other taxiways

Source: Google Earth annotated by the ATSB

Airport diagrams

The airport diagram for the Sunshine Coast Airport in the Aeronautical Information Publication (AIP) Enroute Supplement (ERSA) (Figure 4) and the Departure and Approach Procedure (DAP) chart did not indicate any specific holding point locations. In the additional information section in the ERSA, it did not indicate the distance from the holding point to the runway junction. In addition, the ERSA did not indicate the full length of the runway (2800 m) in black shading, which is used to depict the length of runway available for take-off.

The information in these charts is supplied to Airservices Australia as the publishing body, by the Airport owner. The Civil Aviation Safety Regulations Part 139 Manual of Standards (MOS) Chapter 5 Division 2 Standards for information stipulates what information is required to be presented in the AIP documents. This did not require that holding points be depicted in the diagrams. However, International Civil Aviation Organisation Annex 4 Aeronautical charts section 13.6 (g) required that runway holding positions be marked. Australia had filed a difference with ICAO in relation to this requirement.

In addition, Part 139 MOS did not have a definition of a runway starter extension and did not outline the runway shading requirements when a runway starter extension was present.

Figure 4: ERSA Sunshine Coast airport diagram

Source: Airservices Australia annotated by the ATSB

The Civil Aviation Safety Authority (CASA) aerodrome manoeuvring map for Sunshine Coast Airport (Figure 5) indicated that the entire length of the runway was 2,450 m and did not display the extra 350 m of displaced threshold. Additionally, the placement of holding point Foxtrot was not accurately depicted, with it being shown approximately 110 m closer to the intersection of the taxiway and extended runway. The map did not show the decommissioned runway.

Figure 5: Aerodrome Manoeuvring Map for Sunshine Coast

Source: CASA Aerodrome Manoeuvring Map for Sunshine Coast annotated by the ATSB

Holding point Foxtrot

Holding point Foxtrot was equipped with signage and ground markings to provide flight crews with visual cues indicating their position and proximity to the runway strip (Figure 6). The holding point was also equipped with runway guard lights which sat 30 cm above the ground on either side of the taxiway. These were bright yellow, and flashed when the runway was in operation.

The gable markers at the intersection between taxiway Foxtrot and runway 31 were in an irregular configuration to delineate the extent of the graded runway strip. Due to the location of the taxiway intersecting at the corner of the runway strip, flush rather than raised gables were provided at the taxiway shoulder. The gable that would be within the taxiway has been omitted. These differences were conducted under CASA approval.

Figure 6: Holding point markings, signage and lights

Source: Sunshine Coast Airport annotated by the ATSB

From the control tower, which is approximately 400 meters from holding point Foxtrot, the entire length of taxiway Foxtrot, the holding point and the displaced threshold of runway 31 are visible.

Figure 7: View of holding point Foxtrot from the Sunshine Coast Airport control tower

Source: Air Services annotated by the ATSB

Training and briefings

The operator had multiple training documents on runway markings and signs. Students were also taught ground basics at the commencement of their training. Prior to flying solo to any airport in Class D airspace, the operator required that they complete a competency check. They also had a guidance section which included that ‘the student must first have demonstrated competence on two visits to the same aerodrome without instructor takeover’.

The training school records indicated that the pilot had completed the required competency check for operating to a Class D airspace on 18 April 2023, flying into Archerfield Airport, Queensland. The pilot had also completed 3 training flights to Sunshine Coast Airport, 2 flights with an instructor on 28 March and 4 April 2023, and a solo flight on 5 May 2023. None of these flights had required the use of holding point Foxtrot.

The operator had a briefing for Sunshine Coast Airport that contained:

• a description of class D airspace
• visual meteorological condition (VMC) requirements
• airport facilities including runways and lighting
• communication frequencies for the airport and surrounds
• reference points for training flights
• inbound and outbound information
• ground information.

The information relating to the runways and taxiways contained a graphic of the runway and taxiways at Sunshine Coast Airport (Figure 8) prior to the runway extension and taxiway Foxtrot completion in 2021. The map showed only 2 runway holding points: A1 and A2.

Figure 8: Sunshine Coast Airport map used in the operator airport briefing for students.

Source: Flight Training Adelaide annotated by the ATSB

Pre-flight briefing

On the occurrence flight, the student used the current ERSA for planning and runway information, and the departure and approach procedures (DAP) available at the time for ground information while taxiing at the airport. The student’s instructor reported that prior to the flight, when a briefing of the airport layout was conducted with the student, only holding points A1 and A2, and the location of general aviation parking were discussed.

Other occurrences

The ATSB has investigated previous runway incursions at various locations throughout Australia, including:

• Runway incursion involving Beech Aircraft Corp. 58, VH-NSK Bankstown Airport, New South Wales, on 26 October 2021 (AO-2021-046)
• Runway incursion involving a SAAB 340B, VH-ZRH Carnarvon Airport, Western Australia, on 31 August 2020 (AO-2020-045)
• Runway incursion involving Sling 2, VH-ZSD Moorabbin Airport, Victoria, on 23 July 2020 (AO‑2020-037)
• Runway incursion and communication issues involving Bombardier Dash 8, VH-LQJ, Gladstone, Queensland, on 17 March 2020 (AO-2020-019)
• Runway incursion involving Boeing 737, VH-XZM, resulting in a rejected take-off involving Boeing 737, VH-VZL, Perth Airport, Western Australia, on 28 April 2018 (AO-2018-032)

Safety analysis

The pilot was familiar with the runway configurations at Sunshine Coast Airport having flown to the airport previously. However, having never used taxiway Foxtrot, they were unfamiliar with the length of taxiway from holding point Foxtrot to the intersection with the runway associated with the oblique angle between them, and the displaced threshold on runway 31. Due to this distance of almost 500 m, they incorrectly assessed that they were holding at a taxiway intermediate holding position, despite the visible difference between the marking of runway and intermediate hold points and the correct lighting and signage at the holding point. This error was reinforced when the pilot received instructions to ‘hold short runway 31’, as the change in terminology from ATC led them to believe there was an additional holding point closer to the runway. At this point, and while unsure where any additional holding point might be located, the pilot did not ask ATC for clarification on the instructions and instead proceeded to cross the holding point. As the pilot did not expect to enter the runway strip, they did not scan for incoming aircraft. While they had heard an aircraft being cleared to land, they were unaware of the aircraft’s proximity to the runway.

The controller had given the 737 clearance to land prior to ERE reaching the Foxtrot holding point. At that stage, the landing path for the 737 was clear. The controller visually confirmed ERE had stopped at the holding point and had ensured they had read back that they were to ‘hold short runway 31’ prior to turning their attention to another aircraft. The controller was not required to check the landing path for the 737 again until immediately before the aircraft crossed the threshold. 

Due to the angle of taxiway Foxtrot to the runway, a pilot in the left seat of an aircraft would need to scan for landing aircraft at an angle of 125–130⁰ from directly ahead. As explained in ATSB report AS-2022-001, a normal field of view is approximately 190° (95° either side of the forward view). This would have placed the approaching 737 outside the normal field of view of the pilot of ERE. It is also likely that the pilot was concentrating to the front of the aircraft as they were looking for a holding point. In addition, the pilot was sitting on the left side of the aircraft and so their view would also have been blocked by aircraft structure. This would have required them to move forward in the seat to have visibility of an aircraft on final approach.

The crew of the 737 did not know ERE had crossed the holding point as their view was obscured by the nose of the aircraft. As such, they were unaware of the runway incursion and would likely not have taken evasive action if they had not been instructed to conduct a missed approach. The aerodrome reporting officer (ARO) proactively alerted ATC to the incursion and reduced the likelihood of a serious incident.

The ERSA and the DAP diagrams for the Sunshine Coast Airport did not include holding point locations. While the ERSA was not required to show the locations of holding points, inclusion of this information reduces the potential for confusion or ambiguity around their position. Also, the marking used on the runway diagram to depict the take-off distance available was not accurate. Additionally, the CASA aerodrome manoeuvring map for Sunshine Coast Airport did not give an accurate representation of the holding points or the runway and, if compared to the ERSA, would increase confusion for pilots.

The operator’s briefing documentation on the layout of Sunshine Coast Airport was also not current and did not provide the correct information to students. However, this was found not to have contributed to the pilot’s lack of understanding of the airport taxiway layout and markings as the pilot was using the ERSA for pre-flight planning and the DAP as a location reference while at the airport, and so had the latest available information about the runway layout at the airport.

Findings

From the evidence available, the following findings are made with respect to the Runway incursion involving Diamond Aircraft Industries Inc. DA 40, VH-ERE that occurred at the Sunshine Coast Airport, Queensland on 7 May 2023.

Contributing factors

• The student misinterpreted the instruction given by ATC and their location in relation to the runway, resulting in their aircraft entering the runway strip while a Boeing 737 was on final approach.
• The Airservices Australia‑published Departure and Approach Procedure chart (DAP) for the Sunshine Coast Airport did not indicate the position of the holding point on taxiway Foxtrot, which added to the confusion of the pilot when instructed to hold short of runway 31.

Other factors that increased risk

• The oblique angle of the taxiway to the runway meant that the pilot of the DA 40 would not have had the Boeing 737 within their normal field of view and the 737 pilots on final would not have seen the Diamond as it was obscured under the nose of the aircraft while on final approach. This limited both crew's ability to react without intervention from a third party.
• The Civil Aviation Safety Authority (CASA) Sunshine Coast manoeuvring map did not accurately depict the position of holding point Foxtrot and the large runway displacement.

Other factors

• The aerodrome reporting officer (ARO) proactively alerted ATC to the incursion and as such reduced the likelihood of a serious incident.

Safety actions

Safety action by Flight Training Adelaide

Flight Training Adelaide conducted an internal investigation into the runway incursion and has actioned the following safety actions:

• A notice to crew (NOTAC) was issued to address landings at controlled zones, airports other than home base, and solo flights to controlled zones.
• A qualified flight instructor (QFI) meeting was conducted to communicate the importance of students understanding the signs, markings, lights and phraseology, particularly when at a controlled aerodrome.
• A student meeting was conducted to reiterate the points outlined in the QFI meeting.
• The results of class G and class C & D airspace quizzes appear in the monthly students reports to QFIs.
• Existing tutorials for class D, class C, Sunshine Coast Airport, Archerfield Airport, and Gold Coast Airport were reviewed and updated.
• An exam and quiz specifically for Sunshine Coast Airport has been created.
• Quizzes for Sunshine Coast Airport, Archerfield Airport, and Gold Coast Airport have been made mandatory for all students before visiting these airports.

The operator is also in the process of reviewing the:

• requirements for solo flights to controlled zones, including the requirement for dual flight before any solo flight to any of the training controlled zones
• forms used by QFIs for issuing flight plans in controlled zones.

Safety action by Sunshine Coast Airport

Sunshine Coast Airport, through its safety management process, carried out a review of the occurrence and has undertaken the following safety actions:

• Installed mandatory instruction markings pursuant to Civil Aviation Safety Authority (CASA) Manual of Standards (MOS) 139 section 8.40 - Mandatory Instruction Markings, to further improve the visual characteristics of the runway holding position markings at Foxtrot, the airport (Figure 9).

Figure 9: New runway holding point markings at Sunshine Coast Airport

Source: Sunshine Coast Airport

• Requested an update to the CASA manoeuvring map to correctly identify the runway length, location of displaced threshold and holding point Foxtrot.
• Changed the Aeronautical Information Publication (AIP) Enroute Supplement (ERSA) and the Departure and Approach Procedure (DAP) to reflect the full length of runway 31. Additionally, the distance between holding point Foxtrot and the runway has been added to the additional information section in the ERSA.

Safety action by the Civil Aviation Safety Authority

The Civil Aviation Safety Authority (CASA) has taken the following safety actions:

• provided clarity around the runway shading on ERSA and DAP diagrams
• upgraded the Sunshine Coast manoeuvring map to accurately reflect the airport layout.
• recommended and supported the addition of a runway hotspot depiction at taxiway Foxtrot at the Sunshine Coast Airport to the ERSA and DAP.

CASA further advised that clarification on the terminology and definition of runway starter extensions will be added to the Part 139 MOS. They are also in the process of transferring the Aeronautical Information Package to digital form, which includes transferring all runway maps to digital versions. This will allow a more detailed map to be available.

Sources and submissions

Sources of information

The sources of information during the investigation included:

• the involved pilots and air traffic controller
• Airservices Australia
• Flight Training Adelaide

References

Australian Transport Safety Bureau (2022). AS-2022-001 - Aircraft performance and cockpit visibility study supporting investigation into the mid-air collision involving VH-AEM and VH-JQF near Mangalore Airport, Victoria on 19 February 2020. Canberra: Australian Transport Safety Bureau

Submissions

Under section 26 of the Transport Safety Investigation Act 2003, the ATSB may provide a draft report, on a confidential basis, to any person whom the ATSB considers appropriate. That section 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 following directly involved parties:

• the involved pilots and air traffic controller
• Sunshine Coast Airport
• Flight Training Adelaide
• Qantas
• Civil Aviation Safety Authority
• Airservices Australia

Submissions were received from:

• the air traffic controller
• Sunshine Coast Airport
• Flight Training Adelaide
• Civil Aviation Safety Authority
• Airservices Australia

The submissions were reviewed and, where considered appropriate, the text of the report was amended accordingly.

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 Published by: Australian Transport Safety Bureau © Commonwealth of Australia 2023 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.