[Peetwo]

Popinjay to the rescue with AO-2024-035 Prelim report..etc - 

On 4 September PJ was attributed to this bollocks media spin, announcing the Annex 13 non-conforming (by 53 days) prelim report release for Short investigation AO-2024-035...
   

Preliminary report details passenger 737 flight below minimum safe altitude near Canberra


A preliminary report from the ATSB’s on-going investigation into a flight below minimum altitude incident involving a Boeing 737 south of Canberra notes the operator involved has taken a number of proactive safety actions. 

On the evening of 13 June 2024, the Boeing 737-800 had departed Denpasar, Indonesia, operating Batik Air’s inaugural flight to Canberra, the report details. Forecast tailwinds resulted in an estimated arrival time just prior to 0600 on 14 June, which was earlier than planned, and before Canberra Tower and Canberra Approach air traffic control commenced services for the day. 

The crew elected to proceed, without delaying to wait for those air traffic services to become available, which meant arriving in Canberra using the Canberra Airport CTAF (common traffic advisory frequency – where pilots use radio calls to announce their positions and arrange separation from other aircraft). 

As the aircraft descended in darkness towards Canberra, the crew prepared to conduct the AVBEG 5A standard arrival route (or STAR – which uses satellite-based positioning waypoints to transition aircraft from en route flight to, in this case, an initial approach fix waypoint for Canberra Airport’s instrument landing system approach). 

“While the crew intended to fly the STAR, they did not request this from the air traffic controller managing the airspace,” ATSB Chief Commissioner Angus Mitchell said. 

Instead, the controller expected the crew to track along the clearance previously provided direct to Canberra Airport from the AVBEG waypoint, which is to the north-west of the airport and is also the first waypoint of the AVBEG 5A STAR. 

The crew proceeded with their planned standard arrival route, which meant the aircraft deviated from the cleared track direct to Canberra, and instead tracked to a series of waypoints to the south-west and south of the airport. 
The controller, unaware of the flight crew’s intentions, did not query the deviation, but did instruct them to maintain 10,000 ft to remain clear of a restricted area around the Deep Space Communications Complex at Tidbinbilla to the west of Canberra (this separation is built into the STAR).  

“After receiving this instruction, the flight crew became uncertain as to whether the aircraft would be operating within, or outside of, controlled airspace during the standard arrival route and approach,” Mr Mitchell explained. 
After levelling the aircraft at 10,000 ft, the crew subsequently requested ATC clearance to conduct the instrument landing system (ILS) approach to Canberra. The controller advised them that the Canberra tower was closed and that CTAF procedures applied for the airspace.  

A short time later, when tracking towards the airport from the south and having descended outside of controlled airspace, the flight crew identified they were above the desired flightpath, and the captain decided to conduct a holding pattern at the approach waypoint of MOMBI to reduce altitude. 

“During this holding pattern, the aircraft levelled out at 4,700 ft, but this meant it descended below minimum holding altitude of 5,600 ft, and at one point the aircraft passed 924 ft above terrain,” Mr Mitchell said. 

After rejoining the approach, the aircraft commenced descending again, following the runway 35 glidepath, and it landed without further incident. 

The report notes that while the aircraft was in the holding pattern, a controller in the Canberra Tower was preparing to commence the tower service for the day and they observed the aircraft below the minimum holding attitude. 

“The Tower controller made multiple attempts to contact the crew on the Canberra CTAF, but did not receive a response,” Mr Mitchell explained. 

At about the same time, the Canberra Approach controller commenced for the day – taking over the frequency the flight crew were listening to – and issued a safety alert that the aircraft was operating below the minimum safe altitude. 

The flight crew responded that they were visual with the runway and continued their approach. 

The ATSB’s continuing investigation will consider, among other elements, Batik Air’s procedures, training and route implementation processes, as well as air traffic control procedures and training. 

“A final report with analysis and findings will be released at the conclusion of the investigation, but we note the operator has already pro-actively taken safety actions,” Mr Mitchell concluded. 

“These include revising their Canberra Airport briefing documentation, issuing flight crew notices highlighting procedures for operating in non-controlled airspace, and rescheduling flights to Canberra to ensure they arrive during air traffic control operating hours.” 

Read the preliminary report: Flight below minimum altitude involving Boeing 737, PK-LDK, 19 km south of Canberra Airport, Australian Capital Territory, on 14 June 2024

Publication Date: 04/09/2024

Hmm...I guess Batik Air is fair and uncontroversial game, being as it's an international operator not associated with QF or VA. However what is the point of continuing with this investigation and having PJ contributing 'attributable to' commentary, that effectively says the operator has already addressed the safety issues identified? 

Next we get DTS Dr Godlike being attributed to this media report announcing the release of SAN AO-2024-013-SAN-01

Chipmunk owners urged to ensure rivets are maintained to specifications following Jandakot accident



The ATSB advises DHC-1 Chipmunk maintainers and owners that crashworthiness could be significantly compromised if incorrect specification rivets are used.

The safety advisory notice has been issued as part of the ATSB’s continuing investigation into a fatal accident involving a Chipmunk at Jandakot Airport, WA, on 26 April 2024. 

As detailed in a preliminary report in July, shortly after take-off the aircraft was observed turning to the left at a low height before colliding with the ground, fatally injuring the pilot.

During the ongoing investigation the ATSB has identified that non-specification rivets had been installed on the aircraft, attaching the upper structure between the front and rear cockpits to the fuselage. This structure provides the attach point for the front cockpit shoulder harness.

“Two sets of rivets – 12 in total – attaching the structure to the fuselage sheared during the accident,” Director Transport Safety Dr Stuart Godley said. 

“The ATSB found that the rear row of rivets in each set – that is, three of the six rivets on each side – were pure or near-pure aluminium.”

This meant the rivets did not meet the specification of the relevant modification.

“Testing indicated a significant reduction in strength, estimated to be about one-third of the specification strength,” Dr Godley said.

The rivets would have been originally replaced during the embodiment of modification H.268, issued in 1966 by the aircraft’s type certificate holder at the time, Hawker Siddeley, to replace alloy structure elements with steel.
The aircraft may have modified in the 1960s, however the ATSB has not determined precisely when, or if, the rivets had been replaced since the modification.

It is important to note that while the crashworthiness of the aircraft had been compromised by the presence of non-specification rivets, the ATSB has yet to establish whether it contributed to the outcome of this accident.

However, as there is the potential for other Chipmunks to have incorrect rivets installed in this location, the ATSB determined it was important to bring the issue to the wider attention of Chipmunk operators.

“The ATSB’s safety advisory notice highlights the importance of maintaining aircraft crashworthiness design elements, including its restraint system, to keep the occupant within an aircraft’s ‘living space’ during an accident sequence,” Dr Godley said.

“The use of upper torso restraints such as a shoulder harness can prevent the occupant from striking the surrounding structure during an accident. It is crucial that all components forming part of that restraint system and the structures to which they are attached are maintained to defined specifications.”

The notice therefore advises DHC-1 Chipmunk maintainers and owners to be aware that fitment of incorrect specification rivets where the upper structure between the front and rear cockpits attaches to the gussets on either side could significantly compromise the crashworthiness of the aircraft.

“Those conducting work on aircraft must ensure modifications are carried out to the required specification, or during maintenance returned to that specification,” Dr Godley concluded.

The investigation is continuing, and the ATSB will issue a final report, which will detail findings and analysis, at the conclusion of the investigation.

Read the Safety Advisory Notice: DHC-1 Chipmunks may have incorrect rivets fitted

Publication Date:
11/09/2024

I guess kudos for the proactive initiative of releasing a SAN, however I'm not sure why Dr Godlike needs to be involved? I also query the timetable on when the safety issue was 1st identified to the release of the SAN nearly 5 months after the accident occurred?

Next 'attributed to' DTS Stewie Macleod announcing the release and findings of Short investigation AO-2022-066 (note the excuse for the delay in the investigation):

Saab 340 engine failure due to incorrectly seated coupling securing hydro-mechanical unit to accessory gearbox


The right engine of a Saab 340 flamed out shortly after the aircraft reached cruising altitude, after the engine’s hydro-mechanical unit driveshaft decoupled from the accessory gearbox due to an incorrectly seated coupling, leading to a fuel pump failure, an ATSB investigation report details.

The aircraft, with 2 flight crew, 1 cabin crew and 32 passengers on board, was operating a scheduled Regional Express service from Perth to Albany, WA, on the evening of 21 December 2022.

After climbing to 15,000 ft and establishing a direct track to Albany, the flight crew felt 2 bumps pass through the airframe, and felt the aircraft yaw.

Identifying that the right engine had failed, they conducted the associated checklists, secured the right engine, and returned to Perth where the aircraft landed without further incident.

“The ATSB’s investigation found that the right engine’s hydro-mechanical unit was incorrectly seated, resulting in a misalignment with the engine’s accessory gearbox, leading to significant wear and the eventual decoupling of the hydro‑mechanical unit’s drive shaft from the accessory gearbox,” ATSB Director Transport Safety Stuart Macleod explained.

“As a result, the fuel pump within the hydro-mechanical unit could not function, leading to the engine flameout.”
The engine, a GE Aerospace CT7, was removed from the aircraft for inspection at an authorised CT7 maintenance facility.

“While this inspection put the ATSB investigation on hold for an extended period, it did reveal that the V-band coupling securing the flanges of the hydro-mechanical unit to the accessory gearbox had wear on its inner surface from contact with the accessory gearbox flange,” Mr Macleod noted.

“Interference wear in this area was evidence of a misalignment and non-seating of the hydro‑mechanical unit onto the accessory gearbox.”

Maintenance records showed that the last recorded maintenance that required installation of the hydro-mechanical unit onto the accessory gearbox was during an engine workshop visit at a contractor maintenance facility in February 2018.

“This incident highlights that the incorrect alignment or seating of an aircraft or engine component may not be readily apparent after the installation of a V-band coupling or clamp,” Mr Macleod said. 

“As such it serves as a reminder to maintenance personnel installing V-band couplings to ensure the correct seating and alignment of flanges and the V-band coupling prior to the fitment and torquing of attaching hardware.”

Regional Express has since commenced a fleetwide inspection of its Saab aircraft to confirm the correct fitment of the V-band coupling, while GE Aerospace intends to share the learnings of this occurrence with its customers and maintenance facilities.

Read the report: Engine failure involving Saab 340B, VH-RXE, 141 km south of Perth, Western Australia, on 21 December 2022

Publication Date:
12/09/2024

MTF...P2