Applicability, prescribed method, compliance timing, recordkeeping, and a hazard rationale are the AD’s core concepts, each stated in the text.

• Applicability: The AD applies to specified Alpha Aviation models and serial ranges. The table heading shows the models: HR200‑100, HR200‑100S, HR200‑120, HR200‑120B, HR200/160, and R2100, R2100A, R2112, R2120U, R2160 and R2160D, all with serial numbers 001 up to and including 378 (Applicability). Amendment 1 expressly removes certain aircraft models that are instead covered by EASA AD 2014‑0225 (Amendment 1). The AD thus relies on an inclusive serial number range and model list to delimit scope.

• Prescribed inspection method and source: The inspection must be "in accordance with the instructions contained in Robin Aviation Service Bulletin Number 174 dated 29 November 2000, as in force at the commencement of this AD" (Requirement). That phrase fixes both the procedural source (Service Bulletin No. 174) and the temporal reference (the version effective when the AD commences).

• Who may perform the initial inspection: The AD permits "the pilot in command, other than a student pilot" to carry out the initial engine air intake inspection (Requirement). Subsequent inspections are not given the same explicit permission in the AD text.

• Recordkeeping language: Compliance is to be recorded by entering in the Aircraft Log Book the exact text, “AD/ROBIN/36 Amdt 1 carried out” (Requirement). Any discrepancy found must be recorded in the "Maintenance required" column of the aircraft maintenance release or equivalent document (Requirement). The AD thus separates a compliance evidence entry (logbook) from defect reporting (maintenance release).

• Compliance timing: The AD requires the initial inspection "Before further flight, unless previously accomplished" and then recurrent inspections "at intervals not to exceed 100 hours’ time in service or one year, whichever is the earlier" (Compliance). The AD commences on 29 March 2019 (Compliance).

• Hazard statement and intended safety outcome: The Background sets out a causal chain: the air box sealing felt glued and riveted on the by-pass flap has reportedly caused obstruction of the carburettor, reducing engine power and degrading take‑off performance; in some cases this could lead to uncommanded in-flight engine shut‑down and loss of control (Background). The AD’s objective, by mandating inspection and remedial recording, is to detect and remedy that condition.

• Relationship to other ADs: Amendment 1 removes certain models from applicability because they are covered by EASA AD 2014‑0225, and it amends a compliance note to reflect NZ CAA AD DCA/R2000/31A (Amendment 1, Note). The AD therefore positions itself in a set of overlapping foreign airworthiness directives.

The AD’s mechanics are therefore procedural and record‑based: it does not itself specify a mandatory repair action within the text beyond requiring inspection and defect recording; the remedial detail is delegated to the referenced service bulletin and to maintenance practice once a discrepancy is found. The AD prescribes who may do the initial inspection, the precise compliance wording, and the inspection cadence.

The AD names specific aeroplane models and serial-number ranges, and prescribes actions by pilots, operators, and maintenance personnel. The immediate, named affected parties are:

• Owners and operators of Alpha Aviation model HR200‑100, HR200‑100S, HR200‑120, HR200‑120B and HR200/160 aircraft, serial numbers 001 up to and including 378; and Alpha Aviation model R2100, R2100A, R2112, R2120U, R2160 and R2160D aircraft, serial numbers 001 up to and including 378 (Applicability). The AD’s applicability table is the primary scope limiter. Amendment 1 indicates that some models were removed from applicability because they are covered by EASA AD 2014‑0225 (Amendment 1), so owners/operators of those removed models will need to consult the EASA AD instead.

• Pilots: The AD expressly authorises the "pilot in command, other than a student pilot" to carry out the initial engine air intake inspection (Requirement). That creates a narrow, statutory authorisation for non‑student PICs to perform the first inspection without requiring a maintenance organisation or certificated person, subject to the SB instructions. The AD does not extend that authorisation to student pilots, nor does it explicitly authorise pilots to carry out recurrent inspections.

• Maintenance personnel: The AD obliges that any discrepancy be recorded in the "Maintenance required" column of the aircraft maintenance release or equivalent document (Requirement). Maintenance organisations, licence‑holders, and certifying staff will therefore be engaged, in practice, to correct defects discovered, to complete the maintenance release, and to effect documented repairs per the service bulletin and standard maintenance practice.

• Manufacturers and technical service providers: Robin Aviation (the Service Bulletin originator) is the technical source for required inspection steps. The AD references Robin Aviation Service Bulletin Number 174 dated 29 November 2000 (Requirement). The manufacturer or approved maintenance organisation will be required to provide instructions, parts, or repairs consistent with that SB when defects are found.

• Regulators in related jurisdictions: The AD references New Zealand CAA AD DCA/R2000/31A, and Amendment 1 removes models that are covered by EASA AD 2014‑0225 (Amendment 1, Note). That indicates overlapping regulatory interest; holders who operate or register these aircraft with NZ or EU authorities will need to reconcile obligations under the respective ADs.

• Record custodians: Aircraft owners/operators and the person maintaining the aircraft logbook and maintenance release will be responsible for making the required entries: the precise logbook wording, and the "Maintenance required" column entry for discrepancies (Requirement).

Indirectly affected parties include flight schools (student pilots are excluded from being authorised PICs to do the initial inspection), insurers and lessors who monitor airworthiness compliance, and maintenance data auditors who may be asked to verify the logbook entry or maintenance release.

Who pays: the AD creates inspection costs and potential maintenance costs for the owner/operator. The AD does not allocate funding or specify cost recovery. Who decides: the AD is issued by the Civil Aviation Safety Authority delegate (Pieter van Dijk) and fixes the procedural obligations. What changes: owners/operators must introduce an inspection routine, allow a non‑student PIC to conduct an initial check if they choose, and ensure the exact logbook and maintenance release recording for evidence.

The AD assigns a set of duties, limited rights for a particular actor, and recordkeeping obligations. These are explicit in the Requirement and Compliance entries.

Duties

• Carry out inspection in accordance with Robin Aviation Service Bulletin Number 174 dated 29 November 2000, as in force at the commencement of this AD (Requirement). The AD makes the SB the operative technical standard; the duty is to follow that SB when performing the required inspection.

• Conduct initial inspection before further flight, unless already done, and then repeat the inspection "at intervals not to exceed 100 hours’ time in service or one year, whichever is the earlier" (Compliance). This duty creates two temporal obligations: an immediate pre‑flight check if not previously performed, and ongoing recurrent inspections.

• Record compliance by entering in the Aircraft Log Book the phrase “AD/ROBIN/36 Amdt 1 carried out” (Requirement). This is a precise recording duty to provide evidence that the AD inspection has been effectuated.

• Record any discrepancy disclosed during inspection in the "Maintenance required" column of the aircraft maintenance release or equivalent document (Requirement). The duty separates compliance evidence (logbook entry) from recorded fault reporting (maintenance release).

Rights

• The AD expressly permits the pilot in command, other than a student pilot, to carry out the initial engine air intake inspection (Requirement). That authorisation is narrower than a blanket permission for pilots to perform maintenance; it is specific to the initial inspection and excludes student pilots.

• The AD does not specify a right to defer repair; it requires recording of discrepancies but does not in its text prescribe an explicit timeline for rectification. The AD’s compliance phrase "Before further flight, unless previously accomplished" applies to the inspection rather than to a repair action. The AD does not state the remedial steps to be taken following a discovered discrepancy; those steps will be governed by the referenced Service Bulletin and by applicable maintenance practice.

Recordkeeping obligations and form

• The logbook entry must be the exact phrase provided. That exact wording is part of the duty: “AD/ROBIN/36 Amdt 1 carried out” (Requirement).

• The maintenance release or equivalent must contain the discrepancy in the "Maintenance required" column. The AD uses the term "aircraft maintenance release or equivalent document", thereby allowing for jurisdictional or operator differences in maintenance records, but the duty is to capture the discrepancy in a document that serves the maintenance release function (Requirement).

Delegation and limits

• The AD limits the delegation of the initial inspection to a non‑student PIC. It does not extend the same authorisation to student pilots, nor does it state that subsequent inspections may be performed by pilots.

• The AD delegates technical content to an external document, Robin Aviation Service Bulletin No. 174 (Requirement). The AD therefore imposes a duty to consult and apply that SB.

What the AD does not specify

• The AD does not specify repair actions, timelines for remedial repair, or who must effect repairs. It does not contain enforcement penalties or administrative sanction language. It does not define competence requirements for the pilot‑conducted initial inspection beyond the limitation that the inspector must be a non‑student PIC.

Practical implications: the principal duties are to perform the inspection per the SB, to ensure it is completed before further flight (if not already done), to maintain recurrent inspections on the stated cadence, and to make the mandated logbook and maintenance release entries. The limited right is the explicit authorisation for non‑student PICs to do the initial inspection.

The AD text contains no express penalty provisions, fines, or enforcement mechanisms. It specifies operational obligations (inspection method, timing and recording) and records the delegate who issued it, but it does not set out sanctions or enforcement procedures within the document itself.

What the AD states

• The AD prescribes actions: inspections "Before further flight" and at recurrent intervals (100 hours TIS or one year), requires a precise logbook entry, and mandates that any discrepancy be recorded on the maintenance release (Requirement; Compliance). It records the date the AD commences (29 March 2019) and the issuing delegate (Pieter van Dijk) (Compliance; signature block).

What the AD does not state

• There are no express civil or criminal penalties, no administrative enforcement steps, no prescribed notice or remedial order process, and no statement of consequences for failing to make the required logbook entries or inspections in the text provided. The AD does not reference statutory enforcement provisions or other CASA enforcement measures within its text.

Implications for enforcement in practice (limited to what the AD allows us to say)

• Because the AD mandates actions and prescribes documentation requirements, failure to comply would leave inspection and maintenance records incomplete relative to the AD’s requirements. The AD itself, however, does not set out what administrative consequences flow from non‑compliance.

• The AD cross‑references other ADs (EASA and NZ) in its Amendment 1 and notes. Those foreign ADs may have their own enforcement regimes in their jurisdictions; the AD does not reproduce those regimes.

• The document’s lack of explicit penalties does not mean non‑compliance will have no consequences in practice. The AD is a formal airworthiness directive issued by a CASA delegate; in operational or certification contexts, absence of the required actions or required entries could have implications for inspections, airworthiness certification, or insurer claims. Those are contextual consequences outside the text of this AD.

Limitations on discussion of enforcement

• Any assertion about CASA’s enforcement powers, typical penalty ranges, certificate actions, or other regulatory remedies would be beyond the text of this AD. The AD text itself contains no enforcement schedule or penalty table, so this note records only the absence of such provisions within the AD and the practical consequence that the AD creates evidentiary obligations (prescribed logbook and maintenance release entries) that will be relevant in any subsequent review by regulators, auditors, or third parties.

In short, the AD mandates inspections, recording and defect reporting, but does not in its text specify penalties or enforcement mechanisms. The only enforcement‑relevant content in the AD is the specified obligations and the formal commencement date and signature that establish the AD as a formal directive.

The AD explicitly references other airworthiness directives and situates itself in a network of overlapping regulatory instruments. The text provides direct cross‑references, which shape applicability and compliance interdependencies.

Cross‑references in the AD text

• The AD includes a Note: "New Zealand Civil Aviation Authority AD DCA/R2000/31A refers" (Requirement/Note). This is an explicit cross‑reference to a New Zealand CAA airworthiness directive. The AD also records in Amendment 1 that it "amends the compliance note to reflect DCA/R2000/31A" (Amendment 1). Thus, the Australian AD recognises a parallel NZ instrument and adjusts its compliance note accordingly.

• Amendment 1 removes certain aircraft models from the AD's applicability "which are now covered by EASA AD 2014‑0225" (Amendment 1). This is an express allocation of regulatory territory: models removed from this AD are instead subject to the EASA AD. The AD therefore is not a standalone instrument for all Robin models worldwide; it adjusts scope to avoid overlap with the EASA regulatory instrument.

Regulatory implications

• The AD's references imply that operators who hold registrations or operate across jurisdictions must reconcile obligations among CASA, EASA and NZ CAA ADs. Where the AD removes models because they are governed by EASA AD 2014‑0225, operators of those models must consult the EASA text for their obligations. Likewise, the Note on DCA/R2000/31A invites operators to consult the NZ AD for related guidance or requirements.

• The AD delegates the technical inspection steps to Robin Aviation Service Bulletin Number 174 dated 29 November 2000. Service bulletins are typically manufacturer technical documents; airworthiness directives often make them mandatory. Here, the AD makes the SB the operative technical standard "as in force at the commencement of this AD" (Requirement). Therefore the AD interacts with the manufacturer’s maintenance regime by incorporating the SB as the technical standard of compliance.

Certainty and legal layering

• The AD creates an Australian regulatory requirement that references foreign ADs and a manufacturer SB. That produces a layering: CASA sets the obligation, but the technical description and any repair procedures are in the SB; EASA or NZ ADs may cover some models and contain their own technical prescriptions or timelines. This kind of cross‑referencing requires operators to read multiple documents to understand full obligations.

• The AD’s amendment note shows active coordination: the removal of certain models in Amendment 1 indicates CASA’s effort to avoid duplicative or conflicting directives where EASA has issued an AD covering the same design variants. The AD does not explain the legal mechanics by which a model becomes excluded from Australian coverage beyond the textual note; the operator must rely on the AD's applicability table and Amendment 1 text.

What the AD does not state about interaction with other laws

• The AD does not describe how it interacts with domestic statutory enforcement tools, aviation safety regulations, or certification processes beyond the document’s own requirements and references. It does not cite the enabling statute or administrative provisions that give CASA authority to issue ADs. It also does not spell out whether compliance with the referenced NZ or EASA AD would be treated as compliance with this AD for the models removed by Amendment 1; it simply states that the removed models are covered by EASA AD 2014‑0225.

Operational takeaway

• Operators must check the AD’s applicability list against their airframe serial numbers, follow SB No. 174 as in force at commencement, and note that some models are governed by other ADs. The AD’s cross‑references reduce duplication for some models but increase the documentation an operator must review to ensure full compliance across jurisdictions and registries.

The AD as published is Amendment 1 to AD/ROBIN/36. The text includes a concise amendment note describing the principal changes made by Amendment 1. The AD is dated and signed by the CASA delegate, providing a clear administrative record.

Key items in the amendment history that appear in the text

• Amendment label and date: The document is identified as "AD/ROBIN/36 Amdt 1" and dated 6/2019 in the heading. The bottom of the sheet shows "Pieter van Dijk, Delegate of the Civil Aviation Safety Authority, 19 March 2019" and elsewhere "This AD commences on 29 March 2019" (signature block; Compliance). Taken together, Amendment 1 was issued in March 2019 and commences 29 March 2019.

• Substance of Amendment 1: The AD contains an explanatory line: "Amendment 1 of this AD removes from the applicability certain aircraft models which are now covered by EASA AD 2014‑0225, amends the compliance note to reflect DCA/R2000/31A, and provides further background information in relation to this issue" (Amendment 1). That sentence is the explicit record of what Amendment 1 changed relative to the AD’s prior form.

• Effect on applicability: Amendment 1 removed certain models from the AD’s applicability. The current applicability table in the AD should be taken as amended; the AD’s wording identifies the models that remain under CASA oversight (Applicability).

Administrative record details

• The AD identifies its reference number (AD/ROBIN/36 Amdt 1), the subject (Air Intake By‑pass Flap), and the issuance month/year (6/2019 on the form) (header). It is attested by a CASA delegate and specifies the commencement date (29 March 2019). Those elements constitute the administrative metadata of the amendment.

What the text does not provide

• The AD does not provide the original issue date of AD/ROBIN/36 prior to Amendment 1, nor does it reproduce the earlier text or a change log of earlier amendments. The AD states the corrective adjustments made in Amendment 1 but does not include the previous version for comparison.

• The AD does not include the text of EASA AD 2014‑0225 or NZ DCA/R2000/31A. It only references them. Operators must consult those documents separately to see the content that prompted removal of certain models from this AD.

Practical effect

• Amendment 1 narrows the AD’s scope for some models and aligns compliance notes to reflect related foreign ADs. The practical implication for operators is that they must ensure they are reading the current, amended applicability list and must consult EASA and NZ ADs where indicated. The AD’s abbreviated amendment note gives an administrative explanation for the change but leaves technical conformity and details to the referenced instruments.

Record certainty

• The AD declares its commencement date and is signed by the CASA delegate, providing a clear formal effective date. This ensures a discrete point in time from which compliance obligations in the amended AD are to be measured, including the "as in force at the commencement of this AD" phrasing related to the Service Bulletin.

The AD text contains no litigation history, and no cases are named or cited in the document. There are no judicial decisions, appeals, or challenges recorded in the text provided. The AD includes only technical requirements, a background safety rationale, and an amendment note.

What the AD explicitly contains on this topic

• There is no mention of legal proceedings, appeals to administrative tribunals, or court cases in the AD. No enforcement or dispute resolution procedures are referenced (the AD is silent on litigation).

Consequences of silence in the document

• The absence of litigation history means the AD contains no textual record of disputes about its content, no precedential decisions interpreting the AD’s obligations, and no reported judicial findings on the scope or application of this particular AD.

• For practitioners seeking case law or precedential interpretation, the AD itself does not provide references. Any legal challenges, administrative reviews, or court decisions related to this AD would need to be located in external sources; none are supplied or referenced in the AD text.

Practical guidance given the absence of litigation references

• Rely on the AD’s text for technical and procedural requirements. If there is legal uncertainty about interpretation (for example, the permissibility of subsequent inspections by pilots, or the scope of "before further flight"), the AD itself provides the operative wording and the cross‑references to the SB and related ADs. Any legal questions must be resolved through separate legal research or regulatory inquiry; no litigation precedent is recorded in the document.

• Operators, maintenance organisations, and certifying staff should treat the AD’s text as the primary compliance instrument, and not expect adjudicative guidance from the AD itself. The lack of litigation history in the AD does not imply absence of legal risk; it simply means the AD does not document any adjudicated disputes.

In summary, the AD contains no litigation history. It does not identify cases or disputes, and it does not provide judicial or tribunal interpretation. Any legal contestation or precedent relating to the AD would have to be sought outside the AD text.

This AD contains several precise drafting choices and cross‑references that create potential pitfalls if read hastily. The following are practical risks or traps for owners, operators, pilots and maintenance staff, grounded in the AD wording.

1. Applicability is model plus serial‑number inclusive ranges. The AD lists specific models and serial numbers "001 to and including 378" for two blocks of models (Applicability). Operators must check serial numbers carefully; a wrong interpretation of whether a particular serial falls within "001 to and including 378" could result in mistaken non‑compliance.

2. Amendment 1 removes certain models because EASA AD 2014‑0225 covers them (Amendment 1). If an operator relies on older guidance or an older AD printout, they may incorrectly assume the AD applies to a model that has been removed. Always read the AD’s current applicability table and amendment note.

3. The Service Bulletin reference is time‑tied. The AD requires inspection "in accordance with the instructions contained in Robin Aviation Service Bulletin Number 174 dated 29 November 2000, as in force at the commencement of this AD" (Requirement). That phrase fixes the operative SB version to the one in force when the AD commenced (29 March 2019). If Robin Aviation or another authority has issued later revisions to SB 174 after commencement, the AD does not automatically incorporate them; the operator must use the SB "as in force at the commencement." Operators should secure the correct SB version and verify its status as of 29 March 2019.

4. Pilot‑performed inspection is limited and specific. The AD authorises "the pilot in command, other than a student pilot" to carry out the initial engine air intake inspection (Requirement). The AD does not extend that authorisation to student pilots, nor does it expressly authorise pilots to carry out the recurring inspections. Missing this limitation could lead to improper personnel performing inspections or failing audit checks.

5. Exact logbook wording required. The AD requires the precise entry: “AD/ROBIN/36 Amdt 1 carried out” (Requirement). Variations in wording, punctuation, or omission of "Amdt 1" could be treated as non‑compliant with the AD’s recording instruction. Operators should ensure logbook templates or electronic recording systems can capture the exact text.

6. Separate recording of discrepancies. The AD distinguishes the logbook entry from defect reporting, instructing that "Any discrepancy disclosed in carrying out the inspection shall be recorded in the 'Maintenance required' column of the aircraft maintenance release or equivalent document" (Requirement). Recording a discrepancy only in the logbook, or only in the maintenance release without the required logbook AD compliance entry, would not meet both documentary duties.

7. "Before further flight" applies to the inspection, not the repair, in the AD text. The Compliance clause binds the inspection to pre‑flight timing if not already done. The AD does not in its text explicitly state that any defect must be rectified before further flight, only that discrepancies must be recorded in the maintenance release (Requirement; Compliance). That leaves a potential ambiguity as to whether certain defects require grounding pending repair. Operators must consult the Service Bulletin and applicable maintenance rules to determine remedial action timelines.

8. Recurrent interval combination phrase. The AD sets the recurrent cadence as "not to exceed 100 hours’ time in service or one year, whichever is the earlier" (Compliance). Misreading this could lead to inspections spaced closer or further apart than required. Operators must track both hours TIS and elapsed calendar time.

9. Commencement date and SB version link. The AD commences on 29 March 2019 (Compliance). Because the SB version is tied to "as in force at the commencement of this AD," operators who obtained SB 174 at a different time must verify that they possess the SB version effective as at that date.

10. Interjurisdictional confusion. The AD references NZ CAA AD DCA/R2000/31A and EASA AD 2014‑0225 (Note; Amendment 1). Operators who fly in multiple jurisdictions or who operate aircraft registered overseas must check the relevant foreign ADs for overlapping or differing obligations. Relying solely on the CASA AD without consulting the referenced foreign ADs could leave gaps in compliance if the aircraft is one of the models removed from this AD’s applicability.

11. No explicit repair instructions in the AD text. The AD delegates inspection steps to SB 174 but does not list or require a specific repair action in the AD text. If an operator expects a self‑contained AD that sets repairs, they will be mistaken; the remedial content is in the SB or in maintenance practice.

12. Record custody and proof. The AD’s required logbook entry and maintenance release recordkeeping create potential audit points. Electronic record systems and transfer of maintenance records need to preserve the exact required wording and the maintenance release "Maintenance required" entry for discrepancies.

Operators and maintenance organisations should therefore: verify serial numbers; obtain the correct version of SB 174 current at 29 March 2019; ensure non‑student PICs performing the initial inspection are briefed on SB procedures; set up a system to make the exact logbook entry; capture discrepancy entries on the maintenance release; and review EASA and NZ ADs where cross‑referenced. These are procedural "gotchas" grounded in the AD wording.

Compliance under this AD is procedural and document‑based. Below is a stepwise checklist that follows the AD text verbatim and directs operational steps and recordkeeping. The checklist assumes the reader has immediate access to the aircraft’s serial number, the aircraft logbook, maintenance release, and Robin Aviation Service Bulletin No. 174 dated 29 November 2000.

Step 1 , Confirm applicability

• Check the aircraft model and serial number against the AD’s applicability list. The AD applies to Alpha Aviation model HR200‑100, HR200‑100S, HR200‑120, HR200‑120B and HR200/160, serial numbers 001 to and including 378; and Alpha Aviation model R2100, R2100A, R2112, R2120U, R2160 and R2160D, serial numbers 001 to and including 378 (Applicability). If your aircraft is one of the models removed from applicability by Amendment 1, consult EASA AD 2014‑0225 as noted.

Step 2 , Obtain the correct Service Bulletin version

• Obtain Robin Aviation Service Bulletin Number 174 dated 29 November 2000 and confirm the version that was "in force at the commencement of this AD" (29 March 2019). Use that SB text as the technical standard for the inspection. Do not substitute a later SB revision unless an authorised change to the AD or the SB has been made.

Step 3 , Schedule the initial inspection

• If the required inspection has not already been accomplished, ensure it is done "Before further flight" (Compliance). That means the initial inspection must occur prior to the next flight after the AD’s commencement if not already completed.

Step 4 , Who may perform the initial inspection

• The AD permits the "pilot in command, other than a student pilot" to perform the initial engine air intake inspection. If you intend to have the PIC perform it, confirm the PIC is not a student pilot and that they understand and can follow the SB instructions. If the PIC will not perform the initial inspection, arrange for an appropriately qualified maintenance person to do it.

Step 5 , Carry out the inspection per SB 174

• Follow the steps, checks and acceptance criteria set out in Service Bulletin No. 174 dated 29 November 2000. The AD makes the SB the operative technical standard, so do not omit SB steps.

Step 6 , Record the compliance entry

• After the inspection, record the exact phrasing in the Aircraft Log Book: “AD/ROBIN/36 Amdt 1 carried out” (Requirement). Ensure the entry is made in the appropriate maintenance record location and that whoever signs or certifies the entry is the person authorised to make logbook entries under your organisation’s procedures.

Step 7 , Record discrepancies

• If the inspection discloses any discrepancy, record it in the "Maintenance required" column of the aircraft maintenance release or equivalent document (Requirement). The AD separates the compliance entry (logbook) from discrepancy reporting (maintenance release). Ensure that maintenance release is accessible and that maintenance staff are notified and have the authority to effect repairs.

Step 8 , Remedy defects per SB or maintenance procedures

• The AD text does not specify repair timelines or actions; follow the remedial instructions in Service Bulletin No. 174 and your maintenance organisation’s procedures to rectify any defect. Document repair actions in the maintenance release and related records.

Step 9 , Implement recurrent inspections

• After the initial inspection, schedule recurring inspections "at intervals not to exceed 100 hours’ time in service or one year, whichever is the earlier" (Compliance). Track both flight hours and calendar time to ensure inspections occur on schedule.

Step 10 , Maintain records for audit and transfer

• Preserve the logbook entry with the exact wording and the maintenance release entries for any discrepancies and their rectification. Where records are electronic, ensure they store the exact text and associated metadata (date, signature, certifying person) so they can be reviewed by auditors or inspectors.

Step 11 , Monitor related ADs and SB revisions

• Because Amendment 1 removed some models now covered by EASA AD 2014‑0225 and the AD notes NZ DCA/R2000/31A, monitor those ADs for actions affecting your aircraft. Also confirm whether Robin Aviation issues any new service bulletins or revisions, and check whether CASA issues any further amendments that change the operative SB version or applicability.

Operational notes and risk controls

• If a discrepancy raises doubt about airworthiness, consult the SB, the maintenance organisation's release criteria, and any applicable airworthiness authorities’ guidance before conducting further flights. The AD mandates recording, but does not itself specify whether or when a finding must be rectified before the next flight; prudence and maintenance practice demand that safety-critical defects be dealt with promptly.

• Where the initial inspection is performed by a non‑student PIC, ensure maintenance release and logbook sign‑off processes are followed afterwards. Even if the PIC conducts the inspection, any required repairs will normally need a qualified maintenance person to complete the work and release the aircraft.

• Keep a copy of the AD (AD/ROBIN/36 Amdt 1) with maintenance documentation so that future reviewers can verify exact compliance language and dates.

By following these steps, an operator will satisfy the AD’s explicit obligations: inspection per SB 174 as in force at commencement, pre‑flight initial inspection if not previously done, recurrent inspections on the specified cadence, the precise logbook compliance entry, and recording any discrepancies on the maintenance release.

The AD creates a modest but concrete set of obligations that impose costs and shape behaviour for a small, identifiable set of aircraft owners and operators. The AD’s text and background justify the measure as a safety step; the mechanics determine who pays, who decides, and what practical incentives and costs arise.

Who pays and bearing of costs

• Owners and operators pay the direct compliance costs. Those costs include the labour time for the inspection (whether performed by a non‑student PIC or by maintenance staff), the administrative time to make the required logbook and maintenance release entries, and any parts and labour for repairs if discrepancies are found. The AD does not provide funding or cost mitigation.

• Potential indirect costs include aircraft downtime while inspections and repairs are carried out, operational disruption for flight training or rental operations, and any additional monitoring systems or recordkeeping processes organisations adopt to track the 100‑hour/one‑year cadence.

Who decides

• CASA, through a delegate (Pieter van Dijk), issued the AD, so the regulatory decision is vested in the agency’s airworthiness‑directive process as recorded in the AD. Technical detail and remedial methods are delegated to Robin Aviation via the incorporated Service Bulletin No. 174.

Cost-benefit alignment inherent in the AD

• The AD aims to detect a specific defect: the air box sealing felt on the by‑pass flap that reportedly obstructs the carburettor and reduces engine power, potentially causing uncommanded engine shut‑down and degraded take‑off performance. The benefit is focused and concentrated: reducing the probability of engine power loss during critical phases of flight. The costs are similarly concentrated on operators of the listed models. The AD confines obligations to a finite set of serial numbers, concentrating costs on a definable owner set.

Incentive effects

• Operators gain an incentive to perform timely inspections and remedial action to maintain safety margins and to ensure required documentary evidence is present. The precise logbook wording and "Maintenance required" entry provide incentives to maintain accurate records because those entries are the AD’s compliance evidence.

• The AD authorises non‑student PICs to perform the initial inspection, which creates a short‑term cost‑saving option for operators without immediate access to maintenance personnel. This permission reduces the initial compliance cost and time delay but may create a trade‑off in inspection rigour depending on pilot familiarity with maintenance tasks. There is no authorisation in the AD for subsequent inspections by pilots, so operators will likely use maintenance staff for ongoing compliance.

• Because the AD ties the inspection method to a specific SB version "as in force at the commencement of this AD," manufacturers or maintenance providers may be incentivised to keep the SB up to date; however, the AD prevents automatic incorporation of later SB versions without separate action, which creates an incentive for operators to monitor both SB revisions and regulatory amendments.

Compliance burden, substitution and operational trade‑offs

• The repetitive inspection cadence (every 100 hours or one year, whichever is earlier) imposes a recurring compliance burden. For lower‑utilisation aircraft the calendar year trigger may be binding; for high‑utilisation aircraft the 100‑hour TIS trigger will dominate. Operators must track both metrics and schedule inspections accordingly.

• The AD does not mandate specific repairs within the text, so the cost impact of defects depends on the prevalence and severity of issues found. If inspections frequently reveal felt that needs replacement or re‑seating, repair costs will be recurrent. If defects are rare, the main cost is inspection time.

• The authorisation for PICs to perform the initial inspection creates a substitution effect: operators can shift labour from certificated maintenance staff to pilots for the initial check, reducing immediate certified maintenance demand. However, if defects are found, maintenance staff will be required for repairs and for maintenance release sign‑off, creating a partial substitution for only the initial check.

Concentrated benefits, diffuse costs

• The safety benefit is concentrated on the passengers and pilots of the specific aircraft affected, and the cost is concentrated on their owners/operators. There is no broad industry‑wide burden beyond that owner/operator set. No rents, subsidies, or transfer payments are described in the AD.

Capture, rent‑seeking and market distortion (text‑based limits)

• The AD text shows no mechanism for transfer payments, exemptions, or industry subsidy; it is a technical safety measure. It references but does not compel buying decisions: it requires inspection but does not mandate an upgrade that would alter market competition. Any market distortion would arise only if the cost of compliance causes some owners to ground or retire aircraft, or if the SB requires parts only available via a single supplier; the AD does not state either outcome.

Implementation risk and uncertainty

• The main implementation risk is operational: obtaining and applying the correct SB version, ensuring the PIC or maintenance person conducts the inspection to the SB standard, and maintaining the exact required record entries. The AD’s cross‑references to EASA and NZ ADs add complexity for operators across jurisdictions.

• Because the AD does not specify remedial timelines, there is an operational uncertainty about when a defect must be rectified before flight; that leaves room for varying interpretations depending on maintenance practice and risk tolerance.

In sum, the AD places narrowly targeted inspection and recordkeeping obligations on a defined owner/operator population, shifting inspection costs and some administrative burden onto those parties, while concentrating safety benefits for those operating the affected aircraft. The AD limits duplicative regulatory reach by excluding models covered by EASA AD 2014‑0225 and aligns its compliance note with NZ DCA/R2000/31A, but it does not specify enforcement penalties or repair timelines in the text.

The AD includes an explicit background statement and administrative elements that clarify the safety rationale, the operative documents, and the issuing authority.

Background safety rationale

• The AD sets out the hazard succinctly: "There have been several reports of the air box sealing felt which is glued and riveted on the by-pass flap causing obstruction of the carburettor, preventing the engine from delivering its maximum power. As a consequence, the performance of the aeroplane, notably during take-off, may be significantly degraded. This condition, if not corrected, could lead to an uncommanded in-flight engine shut-down, possibly resulting in loss of control of the aeroplane" (Background). That statement links a particular component (air box sealing felt on the by‑pass flap) to performance degradation and a potential engine shut‑down hazard that could affect control during take‑off.

Administrative metadata

• The AD is presented as "AD/ROBIN/36 Amdt 1" with subject "Air Intake By-pass Flap" and a date marker "6/2019" in the heading. The AD includes an applicability table, a requirement block, a compliance block, and a background block. The AD indicates a commencement date of 29 March 2019 and is attested by the CASA delegate, Pieter van Dijk, dated 19 March 2019 (signature and commencement entries). The AD’s form follows standard AD presentation by listing subject, applicability, requirement and compliance.

Cross‑jurisdictional notes

• The AD explicitly notes the relevance of New Zealand CAA AD DCA/R2000/31A and indicates that certain models are covered by EASA AD 2014‑0225 (Note; Amendment 1). Those points situate the AD within an international set of safety directives and indicate the presence of parallel regulatory action by other civil aviation authorities.

Document scope and limits

• The AD’s substantive content is inspection and recording obligations. It relies on a manufacturer service bulletin for technical content and does not itself specify repair requirements or enforcement penalties. Amendment 1 adjusts applicability to reduce overlap with EASA coverage and updates the compliance note to reflect DCA/R2000/31A.

Signatory and authority

• The AD is attested by "Pieter van Dijk, Delegate of the Civil Aviation Safety Authority" (signature block). The presence of a delegate’s signature and a specified commencement date provides administrative finality and an effective date for operators to measure compliance obligations against.

This completes the source‑grounded deep dive into the AD/ROBIN/36 Amendment 1 text provided.