This instrument is an airworthiness directive (AD) directed at Fokker F28 Mark 0070 aeroplanes that have specific Goodrich main landing gear (MLG) part numbers fitted with pistons that were overhauled by Aerospace NDI (ANDI) Pty Ltd between 25 October 2019 and 18 November 2021 using either the AeroNikl or Atotech plating processes. The AD identifies individual piston serial numbers treated by AeroNikl and Atotech processes, and also captures any other MLG units overhauled by ANDI in that date window using those processes. The directive requires operators to perform a Detailed Visual Inspection (DVI) of the pistons in accordance with Fokker Services All Operators Message (AOM) AOF100.230#5, as in force at the date of this AD. It requires that all affected pistons be permanently removed from service and rendered unsalvageable. The AD imposes a recurring DVI requirement prior to each flight until removal, and establishes removal deadlines that differ by process: pistons overhauled using the AeroNikl process must be removed by the effective date (24 November 2022) and those overhauled using the Atotech process must be removed before 1 February 2024. The AD expressly states that it commences on 24 November 2022 and is signed by the CASA delegate dated 24 October 2022. The background material cited in the AD explains that the action follows notification from the European Aviation Safety Agency (EASA) that ANDI’s overhaul processes were not compliant with SAE/AMS2424, that detailed process sheets are missing, and that the lack of representative test specimens raises risk of internal hydrogen embrittlement which can cause cracking and potential MLG axle piston failure resulting in dual wheel separation. The document also records that earlier action required removal of AeroNikl-affected components by 1 March 2022 under Fokker AOM AOF100.230#3 and that the CASA AD supports the AOM’s requirements; EASA requested the Atotech-affected components be removed before 1 February 2024 to protect the Australian fleet and to avoid introducing affected units into the worldwide supply chain.

The AD is built on a small set of technical and regulatory concepts. First, applicability is a combined match of aircraft model (F28 Mark 0070), Goodrich MLG part numbers (explicitly listed) and piston part number 41141-7, together with identification of the plating process used (AeroNikl or Atotech) and discrete serial numbers assigned to pistons. The AD also captures a residual category covering any MLG overhauled at ANDI under CASA Certificate 1-RT6UE between the specified dates using those processes, regardless of whether the individual serial number appears in the listed sets.

Second, the specific remedial measure is dual: mandatory inspection and mandatory removal. The inspection modality is a Detailed Visual Inspection (DVI) according to Fokker Services AOM AOF100.230#5. The AD requires DVIs to be carried out prior to each flight until the pistons are removed, imposing a recurring, operational inspection obligation. Removal is mandatory and immediate for AeroNikl-treated pistons (by the effective date), and staggered for Atotech-treated pistons (by 1 February 2024). All removed pistons must be permanently removed from service and rendered unsalvageable.

Third, traceability and identification are built into the remedy. The AD notes that pistons are marked by serial number with an engraving near the torque link connection point; that engraving is the proximate mechanism for physical identification on-aircraft. The AD also relies on maintenance and overhaul records (implied by capture of ANDI overhauls during a date range and the use of process names and serial numbers) to relate individual piston units to the implicated plating processes.

Fourth, the causal failure mechanism stated is internal hydrogen embrittlement resulting from non-compliant plating processes and missing process documentation or unrepresentative test specimens. The AD attributes the mechanical risk to hydrogen embrittlement leading to cracking and potential piston failure that can produce dual wheel separation.

Fifth, the AD references interaction with other instruments and standards: it cross-references the Fokker AOM (AOF100.230, earlier editions and #3), points to SAE/AMS2424 as the required process standard that was allegedly not followed, and records EASA involvement in notifying CASA and requesting removal to protect the worldwide supply chain. The AD thus sits at the intersection of manufacturer service messaging, an international technical standard, and regulatory oversight by CASA and EASA.

Each of these concepts is operationalised in the AD through explicit lists, deadlines, and the instruction to render parts unsalvageable, changing the lifecycle and economic value of the affected pistons.

The AD directly affects operators of Fokker F28 Mark 0070 aircraft fitted with specified Goodrich MLG part numbers and piston part number 41141-7 that were overhauled by Aerospace NDI (ANDI) Pty Ltd using the AeroNikl or Atotech plating processes during the date window 25 October 2019 to 18 November 2021. That group includes Australian operators of the F28 Mark 0070 type for whom CASA has regulatory responsibility, because the AD is issued by the Civil Aviation Safety Authority (CASA).

Maintenance organisations and engineers responsible for MLG maintenance, overhaul, and parts replacement for the specified aircraft are affected, because they must perform the Detailed Visual Inspection (DVI) required by the Fokker Services AOM and carry out removal and destruction of affected pistons. The AD specifically references that pistons are engraved with serial numbers near the torque link connection point, so engineering staff charged with parts identification bear responsibility for matching serial numbers to the listed sets and for checking overhaul records that indicate whether ANDI performed the overhaul under CASA Certificate 1-RT6UE.

Aerospace NDI Pty Ltd (ANDI) is implicated as the overhauler whose processes and documentation are central to the safety concern; the AD captures units overhauled by ANDI during the date range. Goodrich, as the MLG manufacturer, and Fokker Services, as the type-support organisation issuing the AOM, are part of the regulatory chain: Fokker provides the DVI procedure via its AOM and Goodrich part numbers are used to define applicability.

Parts suppliers, brokers and the secondary market for landing gear pistons or used components are affected indirectly. The AD requires that removed pistons be rendered unsalvageable, creating a prohibition,by mandatory instruction,on reintroduction of those pistons into service or into the parts supply chain. EASA’s stated concern about preventing affected units entering the worldwide supply chain indicates a cross-border effect on purchasers or sellers of used landing gear components.

Passengers and insurers are indirect stakeholders because the AD addresses a failure mode (hydrogen embrittlement leading to dual wheel separation) that could have operational and safety consequences. However, the AD places the operational compliance burden squarely on operators and maintenance organisations: inspections prior to each flight and removal by the specified deadlines.

Finally, regulators beyond CASA are implicated: EASA is noted as the source of notification and is recorded as requesting removal of Atotech-affected components before 1 February 2024. The AD therefore interacts with international regulatory coordination and with the manufacturer’s AOM.

Key duties imposed by the AD are explicit and narrow: inspect, remove, and destroy.

• Inspect: Operators must carry out a Detailed Visual Inspection (DVI) of the pistons in accordance with Fokker Services AOM AOF100.230#5, as in force at the date of this AD. The AD mandates that the DVI is to be performed prior to each flight until removal. The AD contains a note on identification: the pistons are marked by serial number by an engraving near the torque link connection point. That engraving is the physical marker to link a piston to the lists in the AD.

• Remove and render unsalvageable: All pistons identified as affected must be permanently removed from service and rendered unsalvageable. The AD contains two distinct removal deadlines: pistons overhauled using the AeroNikl process must be removed from service by the AD’s effective date (24 November 2022), while pistons overhauled using the Atotech process must be removed before 1 February 2024.

• Timing and recurrence: The DVI is required prior to every flight until removal. The AeroNikl-affected pieces carry an immediate removal date (effective date), while Atotech pieces have a longer phase-out window.

Rights in this instrument are implicit rather than expressly stated. The AD references compliance with the Fokker Services AOM AOF100.230#5 “as in force at the date of this AD,” which gives operators the right to follow that AOM for inspection technique and standard. The AD also records serial marking on the pistons, which effectively gives operators the ability to identify affected parts without destructive inspection, provided the marking is present and legible.

The AD does not specify alternative methods of compliance (AMOCs), repair options, approved replacement parts, or compensation mechanisms. It does not specify required notification to CASA upon compliance, nor does it specify record-keeping requirements within the text presented here, other than the obligation to render the parts unsalvageable. The AD supports and aligns with Fokker AOM requirements and EASA’s request for removal to safeguard the Australian fleet and the worldwide supply chain.

From the text, operators must determine whether pistons were overhauled by ANDI, which process was used, and whether a piston’s serial number appears in the listed ranges. The engraving near the torque link connection point is the on-part identifier the AD highlights; maintenance records documenting the overhaul by ANDI within the date window are the documentary means to establish applicability. Those determinations are operational responsibilities for operators and maintenance organisations.

The AD text supplied does not set out explicit penalties, fines, or specified enforcement procedures or sanctions for non-compliance. It is an instrument that prescribes mandatory inspections and removal actions with fixed deadlines and an effective date. The AD is signed by a CASA delegate and records the commencement date (24 November 2022). It also cross-references the Fokker Services AOM and EASA’s notification and request.

Because no monetary penalties, suspension powers, or enforcement mechanisms are detailed within the text of this AD itself, the AD should be read as a regulatory direction obliging operators to comply with the measures within the prescribed timeframes. The AD employs enforceable language , “must be permanently removed from service and rendered unsalvageable,” “Prior to each flight, carry out a DVI,” and specified removal dates , which creates clear, obligatory duties. The AD does not, in this text, describe how CASA will verify compliance, whether evidence of compliance must be submitted to CASA or Fokker, or what remedial steps would follow detected non-compliance.

The AD does, however, sit within a regulatory ecosystem: it references actions requested by EASA and supports the Fokker AOM requirements previously promulgated. That ecosystem implies oversight and potential enforcement actions by CASA consistent with its regulatory role, but the AD itself does not enumerate enforcement procedures or penalties. The absence of explicit enforcement provisions in the AD text means that the AD’s compliance requirements are operative and enforceable as regulatory obligations, but the AD leaves the mechanics of enforcement and any penalties outside its express terms.

Operators and maintenance organisations should therefore treat the AD’s directives as mandatory and implement them on the specified timelines, including documentation of inspections and the rendering-unsalvageable process, because the AD creates binding obligations even where the specific enforcement pathway is not set out in this document.

The AD explicitly interacts with a small number of external documents, standards and authorities. It cross-references Fokker Services All Operators Message (AOM) AOF100.230, specifically the current AOM as in force at the date of this AD (AOF100.230#5), and it references an earlier Fokker AOM action (AOF100.230#3) which had required removal of AeroNikl-affected components before 1 March 2022. The AD frames itself as supporting the Fokker AOM requirements: “The subject CASA AD supports the requirements stated within the Fokker all operator message.” Therefore, the AD operates in tandem with manufacturer service instructions rather than replacing them.

The AD also cites the SAE/AMS2424 standard as the plating process specification that ANDI allegedly did not comply with. The AD records that EASA notified CASA that MLG pistons overhauled by ANDI were not compliant with the process contained in SAE/AMS2424, pointing to the standard as the technical benchmark for acceptable plating and testing practice. The AD does not itself modify SAE/AMS2424 but uses non-compliance with that standard as the factual basis for regulatory action.

The document records international regulatory coordination: EASA notified CASA of the non-compliance issue and requested removal of Atotech-affected components before 1 February 2024 so as not to introduce affected units into the worldwide supply chain. The AD thereby aligns an Australian regulatory action with EASA’s request and with manufacturer AOM directives. The AD’s stated aim in background language is to “ensure that the airworthiness of the Australian F28 fleet is safeguarded, and that the affected units are not introduced into the worldwide supply chain,” which places the AD within the international safety oversight framework.

ANDI’s CASA Certificate 1-RT6UE is used in the AD to define the population of overhauled gear: any MLG overhauled at ANDI while ANDI held that certificate during the date range is captured, regardless of whether the specific serial number appears in the explicit lists. Thus, the AD’s applicability is tied to a regulatory certification event for ANDI.

The AD does not list other domestic legislative instruments or cite specific provisions of Australian aviation law in the text supplied. Nor does it set out the relationship between the AD and other civil aviation regulatory instruments such as certificates of airworthiness or operator responsibilities beyond referencing the Fokker AOM. Therefore, readers must construe the AD as operating through established aviation regulatory channels,linking manufacturer service messaging, international regulator notifications, and CASA’s directive,while specific interactions with broader statutory provisions or enforcement mechanisms are not articulated in this document.

The AD document as supplied records a small internal sequence but does not contain an explicit amendment log beyond the references to the Fokker AOM sequence. The AD is titled AD/F28/93, dated 22/2022, and it commences on 24 November 2022. The text records that Fokker Services had previously issued AOM AOF100.230#3, which required the removal of AeroNikl components before 1 March 2022; the CASA AD states that it supports those earlier AOM requirements. The AD in this text references Fokker AOM AOF100.230#5 as the operative inspection procedure “as in force at the date of this AD,” which implicitly acknowledges that the Fokker AOM has undergone at least three prior iterations (including #3), and that the versioning of the AOM matters to the inspection detail.

Outside of that internal referencing, the AD document does not list any formal amendments to itself, nor does it record supersessions, revocations, or later amendments to the AD in the text given. There is no amendment schedule or subsequent effective-dated changes included in this document. The AD’s commencement date and its staged removal deadlines constitute the primary temporal structure set out here. Any later amendment or revocation that might be issued after the date of this AD is not contained in the supplied text.

Practically, the AD establishes two temporal cut-offs: the effective date (24 November 2022) for immediate removal of AeroNikl-affected pistons, and 1 February 2024 for removal of Atotech-affected pistons. Earlier Fokker AOM direction (AOF100.230#3) required removal of AeroNikl components before 1 March 2022; the CASA AD says it supports that requirement. The reference to “as in force at the date of this AD” for the Fokker AOM shows that the inspection procedure is fixed to the AOM edition current on 24 November 2022; any later changes to the AOM are outside the temporal state of the AD unless a later AD amends the applicability or inspection instruction.

The supplied document contains no litigation history, no case names, and no references to court proceedings or administrative appeals. It records factual and regulatory matters: EASA notification to CASA, the Fokker AOM sequence, the overhauler (ANDI), the technical standard (SAE/AMS2424), the safety concern (hydrogen embrittlement), and the required operator actions (DVI, removal, destruction). The AD is signed by a CASA delegate and dated, but the document does not record any disputes, contested decisions, litigation, or precedent.

Because the AD does not include or reference any judicial or administrative decisions, there is no litigation history to summarise within the terms of the source. Any challenge to the AD, any enforcement action taken under other statutory powers, or any case law arising from this AD is not contained in the supplied text.

Several practical and legal pitfalls emerge directly from the terms of the AD and its structure.

Identification and traceability: The AD lists numerous discrete serial numbers for pistons treated by AeroNikl and Atotech, and it captures “any other MLG that was overhauled at Aerospace NDI (ANDI) Pty Ltd as holder of CASA Certificate 1-RT6UE between 25 October 2019 to 18 November 2021 using either the AeroNikl or Atotech plating processes.” The AD notes that pistons are marked by serial number by an engraving near the torque link connection point. If that engraving is worn, unreadable, or absent, operators will need to rely on maintenance and overhaul records to demonstrate whether a piston is affected. The AD therefore places a premium on the availability and accuracy of paperwork covering ANDI overhauls and on the legibility of on-part engravings.

Staggered removal dates: The AD imposes immediate removal for AeroNikl-treated pistons (by the effective date, 24 November 2022) but allows Atotech-treated pistons to remain in service until 1 February 2024, with the interim requirement for DVIs prior to each flight. Mixed fleets or aircraft with pistons of uncertain process provenance must apply the more conservative operational posture (DVI prior to each flight), but defining when to remove depends on establishing whether the process was AeroNikl or Atotech. The difference in deadlines creates operational complexity and potential confusion.

Recurring operational burden: The requirement to carry out a DVI prior to each flight increases pre-flight workload, especially for operators with multiple affected aircraft or tight turnarounds. The AD does not spell out DVI intervals beyond the “prior to each flight” mandate, nor does it state whether the DVI may be performed by the operator’s flight crew or must be certified maintenance staff. The AD directs compliance with Fokker AOM AOF100.230#5 for the DVI technique, but operators must ensure they have appropriate personnel and resources to perform DVIs at the required frequency until removal.

Rendering unsalvageable: The AD requires affected pistons to be “permanently removed from service and rendered unsalvageable.” That phrase extinguishes the residual value of affected parts and eliminates the option to rework or repair them for future use, and it requires a destruction process to be carried out and recorded. The AD does not specify the method or documentation required to demonstrate that parts were rendered unsalvageable, which may create evidentiary disputes if CASA or other regulators request proof of compliance.

Supply chain and replacement parts: The AD does not provide guidance on approved replacement pistons or how operators should source compliant units. The AD’s rationale includes a concern that affected units not be introduced into the worldwide supply chain. Operators must therefore plan for procurement of serviceable, compliant replacements, but the AD does not address availability, lead times or liability for replacement cost.

The AD states explicit steps and deadlines; practical compliance requires operationalising those steps and creating documentary evidence.

1. Identify affected aircraft and parts

   • Use the AD’s applicability clause: confirm whether the aircraft is an F28 Mark 0070 and whether it has Goodrich MLG part numbers listed in the AD fitted with pistons part number 41141-7. Confirm the piston serial numbers by inspecting the engraving near the torque link connection point, which the AD identifies as the on-part serial number marking method.
   • Cross-check maintenance and overhaul records to determine whether the MLG was overhauled at Aerospace NDI (ANDI) Pty Ltd while ANDI held CASA Certificate 1-RT6UE between 25 October 2019 and 18 November 2021. The AD captures any MLG overhauled by ANDI in that period using either the AeroNikl or Atotech processes, so confirm the overhaul date and process in ANDI records.

2. Apply the inspection requirement

   • Perform a Detailed Visual Inspection (DVI) of the pistons in accordance with Fokker Services AOM AOF100.230#5, “as in force at the date of this AD.” Ensure that the personnel performing the DVI have the requisite competence and follow the AOM’s procedures closely. The AD requires the DVI prior to each flight, so implement DVI as a pre-flight task for affected aircraft that remain in service.
   • Keep dated records of each DVI, including who performed it, what was inspected, the AOM version used, and any findings. Where possible, retain photographs or signed inspection checklists to demonstrate that the AOM procedures were followed.

3. Remove and render unsalvageable by the required date

   • For pistons overhauled using the AeroNikl process, remove affected pistons by the effective date of this AD (24 November 2022).
   • For pistons overhauled using the Atotech process, remove affected pistons before 1 February 2024.
   • When removing a piston, carry out and document the removal in the aircraft maintenance logbook and parts history. The AD requires that all pistons be permanently removed from service and rendered unsalvageable; therefore, implement a defined destruction procedure (for example, physical destruction that precludes re-use) and document that destruction with photographs, destruction certificates, serial numbers, method used, date, and responsible person.

4. Prevent re-entry into the supply chain