AD/F50/98 Amdt 1 - MLG Sliding Member End-stop

The AD uses a standard regulator-to-operator prescription model: identify affected aircraft, specify a required course of action by reference to another mandatory document, and set an effective date. Key concepts expressed in the text are:

• Applicability as fleet definition: "Model F27 Mark 050, Mark 0502, and Mark 0604 aircraft, all serial numbers." The AD therefore applies uniformly to every airframe of those models without serial-number carve-outs (Applicability).

• Import by reference: Rather than reproducing detailed maintenance instructions, the Requirement instructs operators to act "in accordance with the requirements of EASA AD 2009-0018" and to consult Fokker and Messier Dowty service bulletins "original issue, or later EASA approved revision" (Requirement, Note). That creates a layered compliance regime where the AD’s legal obligation is fulfilled by following the referenced documents.

• Effective/compliance timing: Compliance is governed by the referenced Requirement document, but the AD amends the effective date to "9 April 2009", and records that the Amendment takes effect on that date (Compliance, Amendment effective date). The AD therefore creates a single date from which the EASA AD obligations are effective in the issuing authority’s jurisdiction.

• Safety defect and causal mechanics: The Background records observable failure modes , "an end stop had unscrewed" and "no lockwire was present on the two lockbolts which hold the end stop" , and the anticipated harm: "structural damage of the main gear and loss of control of the aircraft during the landing roll." The AD frames the remedial action as risk mitigation for that specific mechanical failure.

• Regulatory policy change as legal foundation: The Amendment records that it is responding to a new EASA AD and to an EASA policy change "allow[ing] the issue of Mandatory Continuing Airworthiness action to require correction of unsafe conditions, resulting from production and/or maintenance deficiencies." The AD thus identifies the policy mechanism authorising a mandatory continuing airworthiness action for production/maintenance-derived unsafe conditions.

• No technical change: The text explicitly states "There is no change to the technical requirements of this Directive," signalling that the amendment is procedural/administrative in response to the EASA AD/policy change, rather than imposing different technical steps.

These concepts structure the instrument: a fleet-wide duty by reference to an external AD and service bulletins, tied to a specified effective date, justified by a concrete mechanical failure report and enabled by an EASA policy shift.

The instrument’s applicability clause identifies the primary regulated parties very narrowly and explicitly: operators and owners of "Model F27 Mark 050, Mark 0502, and Mark 0604 aircraft, all serial numbers." That is the full population named in the AD (Applicability). No serial-number exceptions appear in the text.

The Requirement directs action "in accordance with the requirements of EASA AD 2009-0018" and references Fokker Services and Messier Dowty service bulletins (Requirement, Note). Therefore affected parties include those responsible for maintaining the listed aircraft who must obtain and implement the actions in EASA AD 2009-0018 and the referenced service bulletins as issued or in any later EASA‑approved revision. The document does not enumerate roles beyond those obligations; it does not explicitly state separate obligations for owners versus operators versus maintenance organisations. The practical implication of the text is that the persons or entities that carry responsibility for airworthiness and maintenance records for the listed aircraft will be the ones required to ensure compliance because the AD directs remedial action for the aircraft themselves.

The AD does not list additional stakeholders such as part suppliers, lessors, or maintenance providers as separate parties with independent obligations. However the AD’s note referencing service bulletins from Fokker Services and Messier Dowty makes those documents the technical source for corrective action, which typically means maintenance organisations instructed to perform the work must follow the service bulletin procedures (Requirement, Note). The AD does not allocate costs, nor does it identify who will pay for any required parts, inspection or labour. The AD likewise does not offer exemptions or conditional compliance windows for particular operators; applicability is expressed as "all serial numbers", and the effective date is given.

Finally, the AD is presented and signed by a CASA delegate, indicating the issuing regulator (signature block: "David Villiers, Delegate of the Civil Aviation Safety Authority, 24 February 2009"). That positions CASA as the authority issuing the amendment, and by implication the body administering compliance, although the document itself does not spell out enforcement or monitoring mechanisms within its text.

The text imposes a single, central duty: perform the actions required by EASA AD 2009-0018 on the specified aircraft models. The Requirement clause states the duty directly: "Action in accordance with the requirements of EASA AD 2009-0018." This duty is articulated by reference rather than by reproducing procedural steps.

Rights and procedural specifics are not elaborated in this document. The AD gives no express rights text such as appeals, deferrals, or exemptions, and it does not record an administrative review process in this amendment. Where the AD does provide procedural direction, it is to refer to the referenced documents: the EASA AD and the named service bulletins in "original issue, or later EASA approved revision" (Requirement, Note). In practical terms under this instrument, the operator's ability to comply depends on access to those external documents and adherence to their required timelines and technical steps.

The AD does specify temporal scope for duties: compliance is "As specified in the Requirement document, with a revised effective date of 9 April 2009" and the Amendment "becomes effective on 9 April 2009" (Compliance). That establishes the date from which the duty to act applies, but the AD itself does not restate the compliance window or inspection intervals; those remain in the EASA AD and the service bulletins.

The AD asserts a regulatory basis for the amendment, explaining it is issued "in response to a new EASA AD" and that EASA's policy now permits "Mandatory Continuing Airworthiness action to require correction of unsafe conditions, resulting from production and/or maintenance deficiencies" (Background). That statement explains the regulatory power asserted, but the AD does not list rights of affected parties in the event of contested findings or where technical remedies are impracticable.

In short, the AD assigns the duty to carry out the prescriptive actions contained in the referenced EASA AD and service bulletins, effective 9 April 2009, without providing ancillary administrative rights, exemptions, or enforcement procedures within the text of this amendment.

The amendment text does not set out penalties, civil sanctions, or criminal offences. The document is an AD that prescribes required remedial action by reference to EASA AD 2009-0018, and it records the effective date; however, the text contains no express enforcement paragraph, penalty schedule, or procedural enforcement mechanism.

What the document does provide that bears on enforcement is its legal posture and provenance: the AD is issued by the Civil Aviation Safety Authority delegate, signed "David Villiers, Delegate of the Civil Aviation Safety Authority" and dated "24 February 2009." That identifies the issuing authority and date of delegation (signature block). The AD also incorporates by reference the EASA AD and EASA‑approved service bulletin revisions. Enforcement in practice is therefore likely administered through CASA’s usual regulatory framework for airworthiness directives and maintenance compliance, but the amendment itself does not describe that framework.

Because the AD delegates technical instruction to EASA AD 2009-0018 and service bulletins, any compliance schedule, inspection frequencies, or mandatory corrective actions that carry implied consequences would be found in those referenced documents rather than in this amendment text. The AD’s statement that the Requirement document specifies compliance ("As specified in the Requirement document…") means that the concrete remedial steps and any time limits are to be consulted in the EASA AD.

Finally, the document remarks on a policy change at EASA that allowed "Mandatory Continuing Airworthiness action to require correction of unsafe conditions, resulting from production and/or maintenance deficiencies" (Background). That policy change supplies the legal basis or authority, but the amendment text does not convert that authority into a listing of sanctions. The absence of penalty detail in this AD does not equate to absence of enforceability, but the enforcement mechanisms and penalties, if any, are not stated within the instrument itself and must be located in the regulatory enforcement framework outside this amendment or in the referenced EASA AD.

The amendment explicitly situates itself within a network of airworthiness regulation, and the text identifies the following interactions:

• Supranational/regional AD incorporation: The Requirement instructs action "in accordance with the requirements of EASA AD 2009-0018." That is a direct incorporation by reference of an EASA AD into this instrument. Practically, compliance with the Australian amendment is achieved by complying with the EASA AD, as specified in the text.

• Supersession of a prior directive: The Background states that the "EASA AD supersedes the previous CAA-NL AD because a change in EASA AD policy now allows the issue of Mandatory Continuing Airworthiness action..." This records an interaction where an EASA action replaces an earlier CAA-NL (Civil Aviation Authority Netherlands) directive. The amendment in the present text is Amendment 1 issued in response to the new EASA AD; it therefore aligns the issuing authority’s directive with the new EASA policy posture.

• Reference to manufacturer and supplier service bulletins: The AD’s Note references "Fokker Services Service Bulletin SBF50-32-039 original issue, or later EASA approved revision, and Messier Dowty Service Bulletin SB F50-32-62 original issue, or later EASA approved revision." Those service bulletins are technical documents produced by manufacturer/supplier entities and become part of the compliance chain by this cross-reference. The AD thereby connects regulatory obligation to provider technical instructions.

• Procedural and policy grounding: The Background explains that the Amendment is being issued "in response to a new EASA AD" and due to a change in "EASA AD policy" allowing mandatory continuing airworthiness actions to require corrections stemming from production/maintenance deficiencies. This ties an organisational policy change at EASA to the content and authority of this amendment.

• Administrative territorial effect: The AD is issued by the Civil Aviation Safety Authority (CASA) delegate, which places it within Australia's domestic aviation regulatory regime. The instrument imports EASA AD content and service bulletins into that domestic regulatory instrument, demonstrating interplay between EASA prescriptive material and national implementation.

The amendment does not reference domestic legislation, civil aviation regulations, enforcement statutes, or judicial review mechanisms within its text. It does not indicate whether compliance with the EASA AD will be accepted as compliance with any separate national regulatory duty beyond this amendment. The text therefore shows direct interaction with EASA outputs and with manufacturer/supplier service bulletins, and an explicit supersession relationship with a previous CAA-NL AD, but it does not elaborate broader statutory links or enforcement pathways within domestic law in this document.

The document itself is titled and presented as "AD/F50/98 Amdt 1" and dated "4/2009" in the header. The narrative records the following history points:

• The present item is Amendment 1 to AD/F50/98: the heading and repeated lines identify it as "AD/F50/98 Amdt 1" and "MLG Sliding Member End-stop" with date marker "4/2009." That indicates a first amendment to an existing AD numbered F50/98.

• It states the Amendment is "issued in response to a new EASA AD" and that the new EASA AD "supersedes the previous CAA-NL AD because a change in EASA AD policy now allows the issue of Mandatory Continuing Airworthiness action to require correction of unsafe conditions, resulting from production and/or maintenance deficiencies." This explains the reason for the amendment: harmonisation with a new EASA AD and a policy change at EASA.

• The technical requirements remain unchanged: the AD explicitly records "There is no change to the technical requirements of this Directive." Thus Amendment 1 is administrative or jurisdictional in character, aligning local documentation with the new EASA policy and AD, without altering the substantive technical remedy previously prescribed.

• A revised effective date is recorded: the Compliance row says "As specified in the Requirement document, with a revised effective date of 9 April 2009" and again states "This Amendment becomes effective on 9 April 2009." The AD is thus backdated or sets a specific operative date for compliance.

• The signature and date in the document show it was executed on "24 February 2009" by a CASA delegate, David Villiers. That provides the administrative time stamp for issuance preceding the effective date.

The AD does not include prior amendment text or a full change log within this document; it refers to prior directives by reference only (previous CAA-NL AD) and asserts that the new issuance aligns with changes at EASA. It also points readers to the EASA AD and service bulletins for technical detail rather than reproducing any historical technical revisions. Any earlier versions of the AD’s technical requirements or procedural steps are not reproduced here; the document simply notes that technical requirements have not changed and that the amendment is driven by the EASA AD/policy update.

The text contains no litigation history. There are no references to court decisions, administrative appeals, challenge proceedings, or prior enforcement actions in the document. The AD is a regulatory amendment that records a safety incident and administrative response, but it does not report any legal proceedings related to the incident, the AD itself, or the prior CAA-NL AD.

Because the document is an airworthiness directive and not a judicial or adjudicative record, absence of litigation references in the text should not be read as a statement about whether litigation exists elsewhere. Within the four corners of this instrument, there is no litigation history recorded, no citations of judicial authority, and no mention of appeals or disputes. Any judicial or administrative cases concerning the AD, its underlying facts, or related enforcement would need to be sought outside this text. The AD’s background supplies technical incident detail and administrative rationale but does not claim or describe any adjudicative outcomes or legal challenges.

The instrument contains several points that are easy to miss and that have practical consequences for operators and maintenance organisations; the following are drawn directly from the text and its structural choices.

• Applicability is broad and simple: the AD covers "Model F27 Mark 050, Mark 0502, and Mark 0604 aircraft, all serial numbers." That means the rule applies to every airframe of those models. There are no serial-number carve-outs or conditional applicability lines in the text to limit scope (Applicability). Operators cannot assume selective application.

• The AD prescribes compliance by reference rather than by restatement: "Action in accordance with the requirements of EASA AD 2009-0018" and notes particular service bulletins. The AD therefore requires consulting external documents. If a reader relies only on the text of this amendment without obtaining the EASA AD and the named service bulletins (or later EASA‑approved revisions), they will lack the necessary technical prescriptions to be compliant (Requirement, Note).

• The referenced service bulletins are permitted only in "original issue, or later EASA approved revision." That language creates a specificity: only EASA-approved revisions count. Operators must ensure they have the EASA‑approved revision status of any later service bulletin rather than any manufacturer-issued revision that lacks EASA approval. The AD does not specify how to confirm EASA approval status; operators must source that information from EASA or their approved maintenance organisation (Requirement, Note).

• Temporal variation: the AD states compliance is "As specified in the Requirement document, with a revised effective date of 9 April 2009" and that "This Amendment becomes effective on 9 April 2009." Readers must check EASA AD 2009-0018 to see precise compliance windows, because this instrument does not reproduce timing or periodicity (Compliance).

• The AD is administrative in response to policy change but "There is no change to the technical requirements of this Directive." That could be misread: while the technical steps remain unchanged, the legal authority under which the steps are mandated has shifted to a different policy footing. Stakeholders seeking to challenge authority or seeking exemptions must be mindful that the AD records EASA’s policy change as the authority for mandating corrections for "production and/or maintenance deficiencies" (Background).

• The safety issue reported is precise: an end stop "had unscrewed" and "no lockwire was present on the two lockbolts which hold the end stop." The AD’s remedial action is therefore likely to be targeted at securing the end stop and lockbolts. However, this AD does not reproduce the technical remedy, so maintenance teams must not improvise but must follow the referenced service bulletins and EASA AD for the correct procedure (Background; Requirement, Note).

• No penalties or enforcement mechanics are set out: the AD imposes an obligation but does not state sanctions in the document. Parties should not infer the absence of enforcement from this omission; rather, they will need to consult CASA’s enforcement framework or the EASA AD for any stated compliance consequences (Penalties and enforcement).

• Supersession relationship: the AD notes the EASA AD "supersedes the previous CAA-NL AD." If an operator was relying on an earlier CAA-NL AD for technical guidance, they must switch to the EASA AD and the service bulletins referenced here. Failure to update to the new reference set could lead to non‑compliance under this amendment (Background).

These are practical hazards for compliance that arise from how the AD imports external documents, sets a uniform applicability, and leaves technical and enforcement detail outside the amendment text.

Compliance under this amendment is achieved by carrying out the actions set out in EASA AD 2009-0018 and by following the technical instructions in the referenced service bulletins as approved by EASA. The text provides a clear route: consult the Requirement document and the listed service bulletins, then implement their instructions by the revised effective date. Concretely, follow these steps derived directly from the AD text:

1. Confirm applicability: identify whether the aircraft is one of the listed models , "Model F27 Mark 050, Mark 0502, and Mark 0604 aircraft, all serial numbers" , since the AD applies to that entire population (Applicability).

2. Obtain the referenced documents: secure a copy of EASA AD 2009-0018 and the original issues (or later EASA‑approved revisions) of Fokker Services Service Bulletin SBF50-32-039 and Messier Dowty Service Bulletin SB F50-32-62. The AD’s Note requires use of the original issue or any subsequent EASA‑approved revision, not unapproved manufacturer revisions (Requirement, Note).

3. Read the EASA AD for mandated tasks and timing: the AD instructs "Action in accordance with the requirements of EASA AD 2009-0018" and that compliance is "As specified in the Requirement document, with a revised effective date of 9 April 2009." Therefore, consult EASA AD 2009-0018 for precise inspection intervals, corrective steps, and any reporting requirements (Requirement; Compliance).

4. Implement the technical steps as specified in the service bulletins: the Fokker and Messier Dowty bulletins are the technical instructions referenced. Ensure that any parts replacements, torqueing, lockwiring, inspections, or checks are performed to the standard and sequence specified in those bulletins and in the EASA AD, and that any later EASA‑approved revisions are followed where applicable (Requirement, Note).

5. Document compliance: maintain maintenance records showing the EASA AD and service bulletin revision used, the work completed, dates, and personnel/organisation that performed the work. The AD itself does not list record-keeping requirements, but documentation evidencing compliance with the referenced AD will be necessary for any audit or regulatory check given the directive nature of the instrument.

6. Confirm approval status of revisions: where a later service bulletin revision exists, verify that the revision is EASA‑approved before relying on it, since the AD permits "later EASA approved revision." Do not assume manufacturer-issued updates are EASA approved without confirmation (Requirement, Note).

7. Note timing: ensure the actions are completed in accordance with any deadlines within EASA AD 2009-0018 and that the effective date used is 9 April 2009 as stated for this Amendment (Compliance).

8. Coordinate among stakeholders: where the aircraft is operated by one entity but maintained by another (for example, a lessor/lessee or contracted maintenance organisation), ensure contractual responsibility and maintenance procedures are aligned so the remedial actions are completed and logged in the operator’s maintenance records.

9. Where uncertainties arise, consult CASA and EASA: the AD does not spell out enforcement or exemptions. If an operator believes compliance is impracticable, if there are questions about the validity of a service bulletin revision, or if alternative corrective measures are proposed, raise those issues with the regulator or seek guidance from EASA as appropriate. The AD references policy change at EASA as the legal basis, so liaison with EASA or CASA is the appropriate route to resolve procedural uncertainties (Background).

Following these steps, and documenting each action against the EASA AD and the named service bulletins, implements the requirements this amendment imports and satisfies the effective-date constraint recorded in the AD.