[Peetwo]

ATSB recent AAI reports etc.

Via the ATSB website:

Flight below minimum altitude a reminder of high workload during approach, landing



Key points:

- Pilot experienced data entry difficulties during turbulence, which combined with environmental conditions, and timing of clearance from air traffic control, led the pilot to experience high workload;

- Pilot inadvertently selected the incorrect radio frequency during approach, and the aircraft descended below minimum altitude while ATC attempted to re-establish communications;

- Incident is a reminder for pilots of high workload during approach and landing, which can be exacerbated by additional factors such as turbulence.


A pilot’s high workload, including data entry difficulties, while conducting an approach to land at Adelaide Airport in instrument meteorological conditions likely affected their situational awareness resulting in their aircraft descending below the assigned minimum altitude.

An Australian Transport Safety Bureau investigation into the incident details that on the morning of 12 August 2021, the twin-engine Aero Commander 500-S was conducting a private flight from Port Lincoln to Adelaide with a pilot and passenger on board.

After descending to 3,800 ft during the approach, the pilot was cleared by air traffic control to track direct to the GPS waypoint GULLY, the initial waypoint for the area navigation (RNAV) instrument approach into Adelaide.

However, the pilot reported having difficulties entering the RNAV approach into the aircraft’s touchscreen multi-function display due to turbulence.

“Several factors including the environmental conditions, data entry difficulties, and the timing of the clearance for the GULLY waypoint, likely led to the pilot experiencing a high workload,” ATSB Director Transport Safety Dr Stuart Godley explained.

By the time the pilot correctly input the approach into the system, the aircraft had just overflown the GULLY waypoint. This meant when the pilot then selected the ‘Direct-To’ option on the display, the autopilot commanded a sharp turn to the right, to commence an orbit to attempt to overfly the waypoint to recapture it.

The controller then began giving the pilot instructions, intending to vector the aircraft back to the waypoint, but a short time later, communications were lost.

“The ATSB found that during the approach the pilot had inadvertedly selected the incorrect radio frequency,” Dr Godley said.
For about 4 minutes before contact was re-established, the aircraft continued on its assigned heading, but began descending below its assigned altitude.

“During this time, the approach controller attempted to contact the pilot and issued three terrain safety alerts. The lowest altitude the aircraft descended to was 2,480 ft, close to the highest point within 5 NM of the aircraft’s track, which was 1,913 ft.”

Once communications were re-established, the approach controller issued the pilot a terrain safety alert and instructed the pilot to climb immediately to 5,000 ft.

The aircraft then tracked to Adelaide Airport and landed without further incident.

Dr Godley said the event highlights the heightened workload pilots experience during the approach and landing phases of flight.

“Pilots must continuously monitor aircraft and approach parameters, and the external environment, to ensure they maintain a stable approach profile and make appropriate decisions for a safe landing,” Dr Godley said.

“Distractions and unanticipated events can further increase a pilot’s workload leading to undetected errors and a loss of situational awareness.

“During high workload phases of flight, pilots should remain focused on monitoring the aircraft instruments and avoid fixating on a problem.”

Read the report: AO-2021-033: Flight below minimum altitude involving Aero Commander 500 S, VH-LTP near Adelaide Airport, South Australia, on 12 August 2021

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ATSB releases Redcliffe scenic flight accident preliminary report



Key points:

- Investigation is on-going, preliminary report outlines factual information established during the early evidence-collection phase;
- According to witness reports the aircraft’s engine ran rough, then stopped completely, shortly after take-off;
- Pilot attempted to return to the aerodrome but ditched the aircraft 170 m from the shoreline;
- Aircraft flipped over during ditching, coming to rest inverted in about 2 m of water.

The ATSB has released a preliminary report from its on-going investigation into a fatal accident involving a Rockwell International 114 light aircraft near Redcliffe aerodrome, north of Brisbane, on 19 December 2021.

The report, which details factual information from the investigation’s early evidence collection phase, notes that the aircraft departed Redcliffe for a private scenic flight. On board were a pilot and three passengers.

“A number of witnesses located at the airport, in other aircraft, and on the water in boats, observed the accident aircraft take off and retract its landing gear,” ATSB Director Transport Safety Dr Michael Walker said.

“A short time later, witnesses reported that the engine ran rough briefly before stopping completely.”

Another pilot reported hearing the pilot of the accident aircraft broadcast on the radio that they were returning to the aerodrome, and the aircraft was observed to make two left turns, consistent with manoeuvring back to the runway, and extend its landing gear.

“As the aircraft neared the mangrove tree line to the north of the aerodrome, it was observed to descend and ditch into the water of a tidal mud flat, about 170 m from the shoreline,” Dr Walker said.

“During the ditching, the aircraft flipped over, coming to rest inverted in about 2 m of water.”

The pilot and three passengers were fatally injured in the accident and the aircraft was destroyed.

To date, ATSB investigators have recovered and examined the aircraft wreckage, conducted witness interviews,
disassembled and examined the engine, reviewed the aircraft’s maintenance history, and examined security camera footage from the aerodrome.

“As the investigation continues, the ATSB’s investigation will include a disassembly and examination of the aircraft’s propeller, testing engine components, analysis of data recorded from onboard systems, and further analysis of available footage,” Dr Walker said.

“Should a critical safety issue be identified at any time during the course of the investigation, the ATSB will immediately notify relevant parties so appropriate and timely safety action can be taken.”

Read the preliminary report: AO-2021-053 Collision with terrain involving a Rockwell International 114, VH WMM 1 km north of Redcliffe Aerodrome, Queensland, on 19 December 2021

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Powerline survey aircraft stalled at a height too low for recovery



Key points:

- During low-level survey work, a Cessna 172 stalled and entered a spin at a height that was insufficient for recovery;
- Accident highlights importance of managing airspeed and bank angle to minimise risk of stall;
- Operator has made changes to training and checking, and intends to modify their aircraft with an angle of attack indicator and g-meter with recording and data download capacity.

A Cessna 172 aircraft conducting powerline inspections near Canberra stalled and entered a spin at a height too low for recovery before it collided with the ground, an Australian Transport Safety Bureau investigation details.

In the early afternoon of 13 April 2021, the Cessna R172K departed Canberra Airport to conduct powerline surveying to the north of Sutton township, NSW. On board was a crew of two comprising a pilot and an observer.

About three hours into the flight, while manoeuvring to inspect a powerline adjacent to Tallagandra Lane, nearby witnesses observed the aircraft flying low above the trees before it commenced a left turn that continued into a steep descent before colliding with the ground.

The pilot and the observer were fatally injured in the accident, and the aircraft was destroyed.

During the accident flight, according to recorded data and witness accounts, the Cessna transitioned from a level, right turn to the north-north-east into a tighter, possibly climbing, left turn.

From the ATSB’s analysis of the turns conducted by the pilot earlier in the flight, it was estimated that the final turn was likely conducted at a comparatively high angle of bank and closer to the stall speed of the aircraft.

As the manoeuvre continued, the aircraft likely exceeded the critical angle of attack for the wing, causing the wing to aerodynamically stall.

“This investigation reinforces to pilots the importance of managing airspeed and bank angle to minimise the risk of stalling,” ATSB Director Transport Safety Stuart Macleod said.

“This is particularly important when operating in close proximity to the ground, such as conducting low-level air work, as well as during take-off and landing, as recovery may not be possible.”

Mr MacLeod noted the Pilot’s Operating Handbooks for most light aircraft, including the accident Cessna R172K’s, provides stall speed guidelines to avoid a wings level stall.

However, pilots should be cognisant of the raised stall speed when operating turns.

“In a bank the vertical lift component is reduced, and so pilots must pull back on the control yoke to maintain altitude,” noted Mr Macleod.

“This increases the angle of attack of the wing, and if the angle of attack reaches a critical angle, loss of lift and increased drag occurs, and the wing will aerodynamically stall.”

Following the accident, the operator amended the training and checking section of its Operations Manual to incorporate Threat and Error Management and Situational Awareness training modules for powerline low-level survey operations. The amendments enhanced existing topics in the operator’s crew resource management training and stipulated learning outcomes and assessment criteria specific to Threat and Error Management and Situational Awareness.

“The operator also provided detail of intended additions to its low-level procedures to implement an airspeed ‘manoeuvre margin’ that will take into account the increased stall speed associated with steep turns,” Mr Macleod said.

Further, the operator plans to modify its aircraft to include an angle of attack indicator and a g-meter with recording and data download capability.

“These will not only supplement the aircraft’s stall warning device by providing additional warning of an impending stall, but will allow for a record of the maximum and minimum in-flight readings to be downloaded post flight for review,” Mr Macleod said.

Read the report AO-2021-016: Loss of control and collision with terrain involving Cessna R172K, registered VH-DLA near Sutton, New South Wales, on 13 April 2021

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Low-level aerobatics preceded high speed water impact off South Stradbroke Island



Key points:

- Aircraft was conducting low-level aerobatics prior to colliding with water;
- ATSB encourages witnesses, particularly those in the aviation industry, to report concerns regarding unsafe behaviour through confidential reporting channels;
- Investigation found a pre-existing fatigue crack in the aircraft’s elevator bellcrank, although this did not contribute to the accident.

A Yak-52 warbird aircraft had been conducting low-level aerobatics at a height of less than 500 ft above the ground before it collided with water at high speed, fatally injuring the pilot and passenger, an Australian Transport Safety Bureau investigation report details.

The two-seat Yak-52, an ex-military trainer aircraft, departed Southport Airport, on Queensland’s Gold Coast, on the morning of 5 June 2019 for a private aerobatic flight expected to last about 30 minutes. The pilot had owned the aircraft since 2018, and held an endorsement to conduct aerobatics at no less than 3,000 ft above ground level.

When the aircraft did not return to Southport as planned, a search and rescue operation commenced, with part of the aircraft’s propeller located on South Stradbroke Island later that afternoon. The pilot and passenger, who had sustained fatal injuries, and additional wreckage, were recovered from the waters near Jumpinpin channel in the following days.

“The ATSB’s investigation established that prior to the accident the pilot had conducted a number of aerobatic manoeuvres below 500 ft above ground level,” ATSB Director Transport Safety Dr Stuart Godley said.

“While the absence of recorded data for the last phase of flight or witnesses to the accident meant we could not determine with certainty that the pilot was conducting an aerobatic manoeuvre immediately prior to the aircraft’s impact with the water, the ATSB considered it a possibility.”

Dr Godley said the ATSB was able to build a detailed understanding of much of the accident flight, including from air traffic control surveillance radar, which recorded an aircraft over South Stradbroke Island conducting operations with significant track and speed fluctuations, consistent with aerobatic manoeuvres, and witness reports.

Witnesses on South Stradbroke Island reported that they observed an aircraft consistent with the accident aircraft conduct a “loop, cut right, and dive below the tree line”.

“During the accident flight and previous flights, the pilot conducted low-level aerobatics without having completed the required training or having the appropriate endorsement to do so,” noted Dr Godley.

“This would have potentially limited the pilot’s appreciation of the inherent risks associated with low-level aerobatics.”

Dr Godley noted that research shows that pilot perceptions of risk may decrease with repeated successful outcomes, and if a pilot has a history of flights without incident, then they may perceive that they have a lower likelihood of an adverse outcome based on their prior incident-free experiences.

“This accident highlights the inherent risks associated with performing low-level aerobatics where there is a reduced safety margin for recovery,” Dr Godley said.

“Even more so, it demonstrates the importance of being suitably-trained and qualified to conduct these operations.”

The investigation noted that people with aviation experience and knowledge had witnessed the pilot undertake previous low-level aerobatic flights.

While there had been some attempts to communicate concerns about risk-taking behaviour to the pilot, the investigation did not find evidence that the pilot’s behaviour had been formally reported.

“We encourage witnesses, particularly those within the aviation industry, to report any concerns regarding unsafe behaviours through mechanisms such as confidential reporting systems, such as the ATSB’s own REPCON, or the Civil Aviation Safety Authority’s online reporting portal,” Dr Godley said.

“Confidential reporting provides a means to escalate concerns about pilot behaviour while providing protections for the source of the report.”

Dr Godley also noted that the investigation found a pre-existing fatigue crack in the aircraft’s elevator bellcrank, which had the potential to fail in-flight, leading to a loss of control.

Although this crack did not contribute to the accident flight, the finding prompted the ATSB in November 2020 to issue a safety advisory notice to Yak-52 maintainers and owners, emphasisng the importance of dye penetrant inspections to remove defective elevator bellcranks from service.

Read the report: AO-2019-027 Collision with water involving Yakovlev Aircraft Factories Yak‑52, VH-PAE near South Stradbroke Island, Queensland, on 5 June 2019

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Expectation bias from pilot’s greater familiarity with IFR procedures likely led to runway incursion during rare VFR flight



Key points:

- Cleared for Bankstown’s runway 29R, a Beech Baron crossed the runway and entered the occupied runway 29C without clearance;
- The pilot had been conducting IFR flights with the aircraft on a regular basis for the last 18 months but had not operated a VFR flight for some considerable time and had never departed from runway 29R.

The runway incursion of a Beech Baron aircraft onto an occupied runway at Bankstown Airport highlights the potential effect of expectation bias and the importance of pilots focusing on specific instructions given by air traffic controllers, a new Australian Transport Safety Bureau investigation report says.

On the morning of 26 October 2021, the Baron aircraft, registered VH-NSK, and operated by Little Wings, was conducting a post-maintenance flight to test its stall warning system, the investigation report details. Prior to this flight the pilot had not conducted a VFR flight from the airport for some considerable time and had only departed Bankstown from runway 29C for flights over the last previous 18 months. 

Following pre-flight checks, the aircraft was cleared to taxi to holding point A8 for a departure from runway 29R. Once there, the pilot contacted air traffic control (ATC) and advised they were holding short of runway 29R for departure and were advised to hold position. Just prior to this, an Embraer 190 received clearance to enter runway 29C at holding point A2, for high-power engine runs.

Moments later ATC instructed VH-NSK to line-up and wait for runway 29R. The pilot read back their instruction and seeing VH-NSK commence taxiing the Tower controller began assisting two helicopters operating north of the airport. During this time VH-NSK crossed runway 29R and entered and lined up on runway 29C.

Turning back to VH-NSK, the Tower controller issued an instruction for take-off.  When VH-NSK was detected on runway 29C, the Tower Controller immediately called for VH-NSK to ‘hold position, hold position you are lined up on Centre, hold position’ and issued repeated instructions to stop. At the same time, the pilot of VH-NSK saw the Embraer conducting high-power engine runs on runway 29C and did not commence the take-off.

ATSB Transport Safety Director Stuart Macleod said this incident highlights the importance of pilots focusing on the specific instructions given by air traffic controllers and how expectation bias can affect how they receive and understand verbal instructions

“As the pilot of the Baron aircraft had only conducted IFR flights departing from Bankstown’s runway 29 centre for the last 18 months it is likely their focus had narrowed to the actions for the unfamiliar VFR departure and despite confirming their instructions back to ATC they reverted to what they had done previously.

“When issued instructions by air traffic control, pilots need to focus on listening and then repeat what was said in your head and then actively apply that information,” said Mr Macleod.

For more information on runway safety and avoiding errors that lead to runway incursions go to Airservices Australia’s A pilot’s guide to Runway Safety and their specific publications for Bankstown, Moorabbin, Parafield, Jandakot and Archerfield airports.

Read the report: AO-2021-046: Runway incursion involving Beech Aircraft Corp. 58, VH‑NSK, Bankstown Airport, New South Wales, on 26 October 2021

Hmm...all this mad flurry of activity from the Bearded Popinjay's ATSB but still no conclusion to the nearly 4 year investigation in to the Essendon DFO approval process: https://www.atsb.gov.au/publications/inv...-2018-010/ - 

MTF...P2