AD/ECUREUIL/109 Amdt 4 - Sliding Door Rear Fitting Pin

The document sets out a small set of interlocking regulatory concepts that determine what operators must do and when. These concepts, drawn directly from the AD’s headings and text, are: applicability, inspection requirement, replacement/modification requirement, installation prohibition, compliance timing, linkage to manufacturer service data and EASA approvals, and amendment history.

Applicability: The AD specifies the affected helicopter types,AS 350 series B, BA, BB, B1, B2, B3 and D,only when equipped with sliding doors pre-MOD 073298 and/or pre-MOD 073308 (Applicability). That conditions the AD’s reach on both model and the presence of unmodified sliding doors.

Inspection requirement: The AD mandates that persons “check the support shaft of the rear roller and the rear fitting of the sliding door(s) for cracks” and prescribes the inspection method by reference to paragraph 2.B. of Eurocopter AS 350 ASB No. 05.00.47 original issue, or later EASA approved revision (Requirement 1). The AD thereby uses manufacturer service bulletin procedures as the operative inspection method, subject to later EASA-approved revisions.

Replacement and modification requirement: The AD requires replacement of the roller support shaft and fittings in accordance with paragraph 2.B. of ASB No. 52.00.30 original issue, or later EASA-approved revision (Requirement 2). It also makes modification a condition precedent to lawful re-installation of particular sliding doors (Requirement: “No person shall install … unless these sliding doors have been modified per MOD 073298 for LH doors, and per MOD 073308 for RH doors”).

Installation prohibitions by part number: The AD explicitly forbids installation of specified part numbers on any AS 350 helicopter (Requirement: “No person shall install … rail roller pins part number 350A25-1275-20 and cast roller support fittings part numbers 350A25-1270-20 and 350A25-1270-22”). The prohibition operates independently of inspection cycles and applies to maintenance and parts supply decisions.

Compliance timing and intervals: The AD sets different clock starts depending on the recorded flight hours on the sliding door assembly, with explicit initial inspection deadlines and a repeating interval of 110 flight hours, plus a calendar deadline for replacement action (Compliance). The AD also retains that “The compliance times remain unchanged by this issue of the Directive,” signalling continuity across amendments.

Link to EASA and ASBs: The AD repeatedly requires compliance with paragraphs from Eurocopter ASBs and allows later EASA-approved revisions of those ASBs, and it notes “EASA AD 2007-0236 refers” (Requirement; Note). Amendment 4 was issued in response to a new EASA AD, which required repetitive inspections until improved replacement parts were fitted (Background). Thus the AD anchors Australian compliance obligations to EASA-moderated service data and directives.

Amendments and effectivity: The AD records a multi-step amendment history where successive amendments updated which parts must be inspected, replaced, or banned, and how compliance timing was set or extended (Background; “Amendment 1 … Amendment 2 … Amendment 3 … Amendment 4”).

Together, these concepts create a regulatory mechanism that compels operators to inspect, modify or replace hardware, and to avoid installing identified legacy parts and assemblies, using Eurocopter ASBs as the prescriptive technical means and EASA approvals as the certification gate for later revisions.

The AD’s text and structure identify several categories of directly affected parties, all derived from the phrasing “No person shall …”, the Applicability clause, and the technical references to parts, MOD numbers and Eurocopter ASBs.

Aircraft operators and owners: Owners and operators of Model AS 350 helicopters (versions B, BA, BB, B1, B2, B3, D) fitted with sliding doors that pre-date MOD 073298 and/or MOD 073308 are the primary economic subjects of the AD (Applicability). These entities must schedule and carry out the inspections at the specified intervals; where replacement or modification is mandated, they must plan for parts sourcing, downtime, and the labour to accomplish the work in accordance with the referenced ASBs (Requirement; Compliance).

Maintenance organisations and certificated engineers: The AD’s inspection, replacement and installation-prohibition obligations fall on persons who perform maintenance and installation work. The text’s repeated form “No person shall install …” places an affirmative legal prohibition on anyone undertaking installation work with the named parts or assemblies without the required MODs or replacements. Maintenance providers must therefore ensure their procedures and parts inventories comply with the AD and the referenced ASB methods.

Parts suppliers and installers: The AD explicitly bans installation of particular part numbers (roller pins 350A25-1275-20; cast roller support fittings 350A25-1270-20 and 350A25-1270-22). Suppliers who hold stock of these parts, and third-party installers responsible for fitting sliding doors or roller fittings, must be aware that the AD prohibits their installation on any AS 350 helicopter (Requirement). They may have to manage inventory, traceability, and communication with customers.

Regulatory bodies and delegates: The AD is a Civil Aviation Safety Authority (CASA) instrument, signed by the delegate of CASA (signature block), with an effective date (14 September 2007). CASA, through its inspectors and delegated powers, is the decision-making and enforcement authority for this directive’s obligations. The AD also subjects operators to EASA-approved revisions and references EASA AD 2007-0236, meaning that regulatory interaction with EASA-mandated technical actions is functionally relevant.

Manufacturers: Eurocopter is referenced as the originator of the ASBs and MODs: ASB No. 05.00.47 and ASB No. 52.00.30, and MOD 073298 / MOD 073308. The manufacturer’s reporting of failures and metallurgical analysis is cited in the Background as the trigger for amendment actions. Eurocopter’s ASBs and MOD procedures become the prescriptive technical material for inspections and replacements, subject to EASA approval.

Record-keepers and auditors: While the AD does not list record-keeping requirements in this text, the obligations to inspect, to replace parts, and to refrain from installations will create documentary proof obligations for operators and maintainers. The necessity to reference specific ASB paragraphs and EASA-approved revisions means evidence of adherence to the specified service material will be relevant to satisfy regulator scrutiny.

In short, the AD affects operators, maintainers, parts suppliers, the manufacturer, and the regulator. The obligations fall on “persons” conducting installation or maintenance on affected AS 350 helicopters and on owners/operators responsible for ensuring those tasks are performed in accordance with the AD and quoted ASBs.

The AD establishes a set of affirmative duties and negative obligations, stated in mandatory language. It does not enumerate procedural rights such as appeal pathways or waivers within the text; instead it prescribes technical actions and prohibits certain installations.

Affirmative duties:

• Perform inspections for cracks on the rear roller support shaft and rear fitting of sliding doors in strict accordance with paragraph 2.B. of Eurocopter AS 350 ASB No. 05.00.47 original issue, or later EASA-approved revision (Requirement 1). The duty is to follow the ASB’s specified inspection method.
• Replace the roller support shaft and fitting(s) of left and/or right sliding doors as required, in accordance with paragraph 2.B. of Eurocopter ASB No. 52.00.30 original issue, or later EASA-approved revision (Requirement 2). The duty includes adhering to the replacement procedures in the ASB.
• Observe timing and intervals: initial inspections based on sliding-door flight-hours (less than 90 hours or 90 or more hours), with repeat intervals not exceeding 110 flight hours; and meet the calendar replacement deadline (“Unless already accomplished, before 30 September 2007”) where applicable (Compliance).

Negative obligations (prohibitions):

• Do not install sliding doors listed in paragraph 1.A.2. of ASB No. 52.00.30 Revision 1 (or later EASA-approved revision) on any AS 350 helicopter unless those doors have been modified per MOD 073298 for LH doors and MOD 073308 for RH doors in accordance with ASB No. 52.00.30 Revision 1 (Requirement).
• Do not install specific components on any AS 350 helicopter: rail roller pins part number 350A25-1275-20 and cast roller support fittings part numbers 350A25-1270-20 and 350A25-1270-22 (Requirement).

Technical compliance obligation:

• Follow the Eurocopter ASBs identified and, where later EASA-approved revisions exist, use those later revisions as permitted. The AD repeatedly conditions inspection and replacement methods on the specified ASB paragraphs and any later EASA-approved revision, thereby delegating the technical standard-setting to those documents (Requirement).

Rights and procedural notes reflected (or absent):

• The AD permits the use of later EASA-approved revisions of the referenced ASBs, which gives operators and maintainers the right to comply with updated (EASA-approved) technical procedures rather than being locked to the original issue (Requirement). This is a procedural flexibility explicitly noted.
• The document does not stipulate appeal, exemption, or alternate means of compliance within its text. It also does not specify record-keeping, reporting channels, or penalties for non-compliance in the body of the text. The absence means that any rights (for example, to seek an exemption or to propose an alternative method of compliance) must be inferred from the regulator’s broader procedures, not from this AD’s text.

Duties on timing and flight-hour thresholds:

• The AD prescribes different initial inspection schedules depending on whether a sliding door has logged less than 90 flight hours (inspect upon accumulating 110 flight hours and then every 110) or 90 or more flight hours (inspect within 20 flight hours after 26 October 2006 and then every 110 flight hours). Operators must therefore ascertain the flight-hour history of the sliding door assembly to determine the correct inspection start time and manage the recurring inspection schedule (Compliance).

Delegation and effectivity:

• The AD is issued by the Civil Aviation Safety Authority (delegate signature) and becomes effective on 14 September 2007. The duty to comply is therefore time-bound and enforceable from that effective date as stated (signature block; “This Amendment becomes effective on 14 September 2007”).

To summarise, the AD creates operative duties to inspect and replace specified components according to Eurocopter ASBs (and later EASA-approved revisions) and negative obligations to avoid installing certain doors and part numbers unless modification or replacement conditions are satisfied. The AD does not itself enumerate appeal rights, exemptions, or explicit sanctions within the text provided.

The text of the AD sets out mandatory technical requirements, prohibitions on installations, compliance times and an effective date, but it does not include explicit penalty provisions within the body of the instrument. Enforcement and any sanctioning mechanisms are therefore not articulated in this document; instead, the AD establishes obligations that will be enforced by the Civil Aviation Safety Authority through its regulatory powers as represented by the delegate’s signature (signature block: “Charles Lenarcic, Delegate of the Civil Aviation Safety Authority”), and by the AD’s stated effective date (“This Amendment becomes effective on 14 September 2007”).

The mechanism for enforcement implicit in the AD consists of:

• Mandatory compliance deadlines and intervals: the AD prescribes fixed inspection intervals (every 110 flight hours once initial thresholds are met) and specific calendar deadlines for replacement actions (“Unless already accomplished, before 30 September 2007”), giving regulators concrete benchmarks against which to assess compliance (Compliance).
• Explicit prohibitions: the AD contains categorical prohibitions on installation of certain sliding doors and specific part numbers (Requirement). The phrasing “No person shall install …” provides a clear legal proscription for regulated behaviour and is an enforceable obligation within the regulatory context.

What the AD does not specify:

• The AD text does not state civil or criminal penalties, fines, suspension of certificates, or other administrative sanctions for non-compliance. It likewise does not identify an inspection or audit regime, nor does it list reporting procedures for discovered cracks, replacement entries or modifications. Those elements are not included in the AD as supplied.
• The AD does not set out a formal process for requesting an alternative method of compliance, nor does it provide procedural guidance on reporting compliance to CASA within the instrument text. If such processes exist, they are external to this AD and would need to be sourced from CASA’s broader regulatory instruments or guidance material.

Interaction with EASA and other directives:

• The AD notes that it refers to EASA AD 2007-0236 and that Amendment 4 was issued in response to a new EASA AD requiring repetitive inspections until replacement with improved parts and prohibiting installation of part 350A25-1270-22 on any AS 350 helicopter (Background). This cross-reference means that enforcement and compliance expectations are aligned with EASA’s supervisory actions, and non-compliance could be assessed against both CASA’s AD and the referenced EASA requirements as technical standards.

Practical enforcement implications:

• Because the AD delegates technical procedure to specific Eurocopter ASBs (and later EASA-approved revisions), enforcement will look to whether the inspections, replacements and installation prohibitions were carried out in accordance with those ASB paragraphs and within the stated timeframes. Evidence of compliance would therefore be documents and maintenance records demonstrating the referenced ASB procedures were complied with.
• The AD’s effective date (14 September 2007) provides the regulator with a clear temporal cut-off from which to judge whether the obligations were met, and the calendar deadline (“before 30 September 2007”) gives a further compliance milestone.

In summary, the AD sets mandatory technical obligations and prohibitions and identifies effective timings, but does not itself articulate penalty schedules or enforcement procedures in the supplied text. Enforcement will be exercised by CASA under its regulatory authority with compliance assessed against the AD’s explicit technical and timing requirements and the referenced ASB/EASA materials.

The AD integrates and cross-references manufacturer service documentation and a relevant EASA airworthiness directive, thereby creating compliance obligations that link Australian regulatory action with international regulatory and manufacturer technical standards.

Linkage to Eurocopter ASBs: The AD’s inspection and replacement mandates are expressed by direct reference to Eurocopter Alert Service Bulletins: paragraph 2.B. of ASB No. 05.00.47 for inspections of the rear roller support shaft and rear fitting, and paragraph 2.B. of ASB No. 52.00.30 for replacement of the roller support shaft and fittings. The AD expressly permits compliance using those ASB paragraphs or “later EASA approved revision[s]” (Requirement). This means that operators’ compliance duties are procedurally defined by the manufacturer’s service material, subject to EASA approval, rather than by bespoke technical text in the AD.

Reference to EASA ADs: The AD contains a note that “EASA AD 2007-0236 refers” and Background explicitly states that Amendment 4 was issued in response to a new EASA AD requiring repetitive inspections until replacement with improved parts and prohibiting installation of part 350A25-1270-22 on any AS 350 helicopter. The AD therefore incorporates, by reference and alignment, the safety actions and technical conclusions of an EASA directive. For operators, that creates a harmonised set of obligations between CASA and EASA for these specific airworthiness concerns.

MODs as conditions: The AD conditions lawful installation of certain sliding doors on the presence of modifications performed per MOD 073298 (LH doors) and MOD 073308 (RH doors) as documented in ASB No. 52.00.30 Revision 1. The MOD numbers are manufacturer modification identifiers. The AD’s coupling to MODs means the regulatory effects hinge on a known set of manufacturer modifications that alter component geometry, material or attachment methods. The legal effect is that only doors that have been modified in accordance with the specified MODs (and therefore documented in service records) may be re-installed lawfully where the AD would otherwise prohibit their installation.

Interplay with aircraft maintenance and certification frameworks: The AD imposes mandatory inspection and replacement activities that must be performed using the referenced ASB procedures; in practice, those activities intersect with certificate-holder maintenance programmes, continuing airworthiness records, and the quality-control and release-to-service functions performed under Australia’s maintenance regulatory framework. While not stated in the AD text, this linkage is implicit because the AD defines what must be done technically and when, leaving record-keeping and release-to-service actions to standard maintenance regulatory processes. The AD does not itself set out these broader procedural requirements, but it prescribes the underlying technical standards that must be satisfied within those processes.

Absence of explicit statutory references: The AD does not quote or restate provisions of primary statute or regulation within the text provided. There is no enumeration of the statutory power under which the AD is issued or of specific penalties under an Act; the instrument is presented as a directive from the Civil Aviation Safety Authority (delegate signature). As such, the AD operates by invoking CASA’s regulatory authority without reproducing the enabling statute in the instrument text.

Overall, the AD functions as a focused regulatory instrument that binds operators to Eurocopter’s ASB procedures (as EASA-approved), aligns CASA action with an EASA AD, and conditions installation activities on execution of specific MODs. Its practical legal effect will be determined by how CASA enforces the directive within the broader Australian aviation safety regulatory framework and by operators’ adherence to the referenced ASBs and EASA approvals.

The AD records a serial amendment process in its Background paragraph, summarising four prior amendment events that shaped the AD’s current content. The text gives a short narrative account of the problem and how successive amendments changed the requirements.

Initial trigger and early amendments:

• The manufacturer reported failure and cracking of the sliding door rear roller support pin, with investigation revealing cracks initiating from a spring pin bore and subsequent fatigue growth; metallurgical analysis revealed a heat treatment non-conformity in the pin material (Background). Those findings led to the original AD action set out in the document.
• Amendment 1 followed reports of cracking and failure of the roller support shaft rear attaching fitting, prompting additional action to address that fitted geometry and attachment point (Background).

Conversion to ASB and mandated modification:

• Amendment 2 converted a Requirement document into an Alert Service Bulletin (ASB) with the same reference number and mandated modification action that “cancels the inspection requirements of this Directive” (Background). In other words, Amendment 2 replaced recurring inspections, in appropriate cases, with a mandated modification that eliminated the need for continued inspections. That change reflects a standard regulatory progression from inspection regimes to structural design fixes where practicable.

Compliance timing adjustment:

• Amendment 3 extended the compliance time for Requirements 2, 3 and 4 (Background). The text does not restate the exact new compliance times here but records the fact of extension, indicating that the regulator moved to give operators more time to meet certain obligations,presumably to accommodate parts availability, operational constraints, or implementation issues.

Amendment 4 (this document):

• Amendment 4 was issued in response to a new EASA AD, which required repetitive inspections until replacement of current parts with improved parts and also prohibited installation of roller support fitting part number 350A25-1270-22 on any AS 350 helicopter (Background). This Amendment therefore reintroduced or retained repetitive inspection obligations alongside replacement requirements and added an absolute installation prohibition on a specified fitting part number. The AD states that “This Amendment becomes effective on 14 September 2007” and notes that “The compliance times remain unchanged by this issue of the Directive” within its Compliance section.

Other amendment mechanics:

• The AD incorporates a procedural feature common to such directives: the prescription of work by reference to specific ASB paragraphs and later EASA-approved revisions. That means amendments can be operationalised through updated ASBs that are EASA-approved without each technical tweak requiring a separate amendment to the AD text, provided the AD continues to reference “later EASA approved revision[s]”.

Constraints in the record:

• The AD’s Background summarises the amendments but does not reproduce the exact text changes for each numbered amendment. It notes the causal inputs,field reports, metallurgical analysis, EASA coordination,and records the policy moves (inspection, modification, calendar extensions, prohibition of part installations).

In short, the AD shows an evolutionary amendment pattern: an initial inspection regime to address detected cracking, follow-on actions when additional cracking modes were reported, conversion to a mandatory modification where feasible (thus cancelling inspection requirements for modified parts), later extensions of compliance times, and, in the latest amendment, alignment with an EASA AD that retained inspections until parts were replaced and prohibited an identified part number. The document’s amendment history therefore reflects the standard regulatory response sequence from immediate inspection to design modification, interspersed with timing adjustments and harmonisation with international regulator (EASA) action.

The AD as provided contains no record of any litigation or court proceedings concerning its validity, interpretation, or enforcement. The instrument’s text includes a Background narrative, compliance requirements, prohibition clauses and an effective date, but it does not cite any cases, legal challenges or judicial determinations, nor does it reference adjudicative outcomes.

Implications of the absence of litigation in the AD text:

• The AD itself is an administrative safety directive produced by the Civil Aviation Safety Authority and designed to be complied with by operators and maintainers. The absence of litigation citations in the instrument means that any legal disputes that may have arisen (if any) are not recorded here and cannot be inferred from this text.
• The AD does not set out internal review or appeal mechanisms in its language. In practice, administrative instruments of this kind are typically subject to the broader statutory and regulatory frameworks of the issuing regulator for remedies and challenges. However, those mechanisms are external to this AD and are not described within the supplied document.

Consequences for practitioners:

• When advising clients on compliance risk, practitioners must rely on the AD’s explicit technical and timing obligations and on the regulator’s enforcement authority as represented by the delegate’s signature and effective date (“This Amendment becomes effective on 14 September 2007”; signature block). Any legal recourse, challenge, or interpretation dispute would therefore be pursued in the usual fora under the statutory regime that empowers the regulator; this AD does not specify such procedures.
• Because the AD cross-references EASA AD 2007-0236 and requires compliance with Eurocopter ASBs (or later EASA-approved revisions), disputes about technical sufficiency, alternative compliance means or interpretation of ASB paragraphs would likely involve both regulator and technical expert evidence. The AD does not provide a litigation history indicating how such disputes have been resolved previously.

Advisory note drawn strictly from the document:

• The AD’s content and amendment history indicate iterative regulatory action in response to field reports and an EASA AD. The absence of litigation history in the AD text does not demonstrate whether challenges were pursued elsewhere; it simply means no litigation record is incorporated into this instrument. Any practitioner needing to know whether litigation has occurred must consult external legal records and CASA administrative records outside the AD itself, because those sources are not contained in this document.

The AD contains several specific features and potential pitfalls that could catch operators, maintenance providers and parts suppliers if not carefully monitored. These are drawn directly from the AD’s language and structure.

Part-number prohibitions are absolute: The AD expressly bans installation of rail roller pins part number 350A25-1275-20 and cast roller support fittings part numbers 350A25-1270-20 and 350A25-1270-22 on any AS 350 helicopter (Requirement). That prohibition is unconditional in the text; it is not conditional on an aircraft’s flight hours or modification state. Parties must therefore ensure that inventory control systems, procurement decisions and maintenance release-to-service checks prevent these parts being fitted under any circumstances.

Installation prohibition tied to MODs and ASB paragraph references: The AD prohibits installation of sliding doors listed in paragraph 1.A.2. of ASB No. 52.00.30 Revision 1 (or later EASA-approved revision) unless those doors have been modified per MOD 073298 (LH) and MOD 073308 (RH) in accordance with ASB No. 52.00.30 Revision 1. The gotcha is that compliance depends on the combination of identifying whether a door is one of the listed assemblies in paragraph 1.A.2 of the ASB, confirming whether it has been modified per the correct MOD number, and ensuring the modification was performed “in accordance with” the named ASB revision. Operators must therefore retain traceable records linking installed doors to MOD compliance, and maintain their own familiarity with the specific ASB paragraph referenced.

Flight-hour thresholds determine initial inspection timing: The AD sets different initial inspection triggers based on whether sliding doors have logged less than 90 flight hours or 90 or more flight hours (Compliance). Operators must have accurate flight-hour logs specific to the sliding door assembly to determine whether the initial inspection is at 110 flight hours (for doors <90 hours) or within 20 flight hours after 26 October 2006 (for doors ≥90 hours). Misreading the threshold or failing to segregate door assembly hours from aircraft hours could lead to premature missed inspections or unnecessary inspections.

Repetitive inspection intervals must be observed precisely: Once the initial inspection is done, the AD requires inspections “thereafter at intervals not to exceed 110 flight hours” (Compliance). Maintenance planners must therefore schedule and document recurring inspections on that interval. Failure to adhere to the 110-hour max interval exposes the operator to regulatory non-compliance.

Calendar deadline ambiguity and obligation sequencing: The Compliance section includes a standalone line “2. Unless already accomplished, before 30 September 2007.” The AD text does not restate in this segment which specific Requirement “2.” refers to, though by placement it links to replacement actions in the Requirement list. Because the AD’s text does not explicitly restate the referenced Requirement text here, there is a risk of misinterpretation about which action is mandatorily to be completed by that date. Operators should interpret the calendar requirement conservatively and align with the AD’s earlier Requirement language and the referenced ASB paragraphs to determine which replacement actions were intended to have that deadline.

Dependence on external documents and “later EASA-approved revisions”: The AD repeatedly defers the precise inspection and replacement procedures to paragraphs of Eurocopter ASBs and permits later EASA-approved revisions. That creates two practical issues: first, operators must obtain and use the correct ASB and the correct paragraph (paragraph 2.B.); second, they must ensure that any later revision they rely on is EASA-approved. Relying on an unapproved ASB revision or an incorrect paragraph could result in technical non-conformance with the AD.

Effective date versus compliance milestone dates: The AD becomes effective on 14 September 2007, while some compliance timings are tied to earlier calendar dates (e.g. “within 20 flight hours after 26 October 2006” for certain doors). Operators should be careful to reconcile effective dates, retrospective timing triggers and the applicable flight-hour calculations to ensure they meet the AD’s obligations even where the AD’s effective date post-dates the initial inspection trigger referenced.

Scope limitation by MODs: The applicability clause limits applicability to helicopters equipped with sliding doors pre-MOD 073298 and/or pre-MOD 073308. The gotcha is that an aircraft retrofitted with doors that have already incorporated those MODs may not be subject to the same inspection obligations. Determining whether a door is “pre-MOD” requires checking mod status in aircraft and component records, and such checks must be done with care.

Recordation and evidence of compliance: The AD requires actions to be carried out “in accordance with” the referenced ASB paragraphs. While the AD does not itself list record-keeping requirements, proof of compliance will necessarily depend on documentary evidence (maintenance entries, ASB compliance sheets, parts invoices and MOD compliance documentation). Operators should treat the AD as imposing an implicit documentation burden even though it is not explicit in this text.

In sum, the principal practical pitfalls are: absolute bans on specific part numbers; conditional installation approvals tied to named MODs and ASB paragraphs; flight-hour-specific inspection triggers; a repeating 110-hour interval; dependence on EASA-approved ASB revisions; and potential ambiguity in the calendar deadline’s precise scope. Each of those items requires careful administrative and technical controls to avoid inadvertent non-compliance.

Compliance under this AD requires a sequence of identification, inspection, modification or replacement, and prevention of prohibited installations, executed in accordance with the specified Eurocopter ASB paragraphs or later EASA-approved revisions. The following steps translate the AD’s text into a practical checklist grounded on the AD’s explicit requirements.

1. Confirm applicability:

   • Determine whether the helicopter is Model AS 350, version B, BA, BB, B1, B2, B3 or D.
   • Confirm whether the helicopter is fitted with sliding doors that are pre-MOD 073298 (LH) and/or pre-MOD 073308 (RH) (Applicability). If the doors are post-MOD, the AD’s inspection and replacement requirements may not apply in the same way; verify MOD status via logbooks and component records.

2. Ascertain sliding-door flight hours:

   • For each sliding door assembly, determine the accumulated flight hours. The AD prescribes different initial inspection timing depending on whether the sliding door has logged less than 90 flight hours or 90 or more flight hours (Compliance). Ensure door-specific hour tracking is in maintenance records.

3. Perform the initial inspection per the ASB:

   • If the door has logged less than 90 flight hours: inspect upon accumulating 110 flight hours on that door, then repeat every 110 flight hours thereafter.
   • If the door has logged 90 or more flight hours: unless already inspected, perform the initial inspection within 20 flight hours after 26 October 2006, then repeat every 110 flight hours thereafter (Compliance).
   • Execute the inspection “in accordance with paragraph 2.B. of Eurocopter AS 350 Alert Service Bulletin No. 05.00.47 original issue, or later EASA approved revision” as the AD requires (Requirement 1). Use the ASB’s prescribed methods, tools, and inspection criteria.

4. Replace components as required using the ASB:

   • Where inspection findings or the AD require replacement, replace the roller support shaft and fitting(s) of the left and/or right sliding doors in accordance with paragraph 2.B. of ASB No. 52.00.30 original issue, or later EASA-approved revision (Requirement 2). Follow the ASB's step-by-step replacement procedures, part numbers for improved components, and installation torques/clearances as specified.

5. Meet calendar replacement deadlines:

   • Where the AD sets a calendar deadline (“Unless already accomplished, before 30 September 2007”), ensure the relevant replacements or modifications have been completed by that date unless they were already accomplished prior to the AD. Interpret the calendar deadline conservatively as referring to the replacement/modification Requirement that precedes the compliance note (Compliance).

6. Avoid prohibited installations:

   • Do not install sliding doors listed in paragraph 1.A.2. of ASB No. 52.00.30 Revision 1 (or later EASA-approved revision) on any AS 350 helicopter unless those sliding doors have been modified per MOD 073298 for LH doors and per MOD 073308 for RH doors in accordance with ASB No. 52.00.30 Revision 1 (Requirement).
   • Do not install rail roller pins part number 350A25-1275-20 or cast roller support fittings part numbers 350A25-1270-20 and 350A25-1270-22 on any AS 350 helicopter (Requirement). Purge these part numbers from allowable fitment lists and inventory where necessary.

7. Use only the prescribed ASB paragraphs and EASA-approved revisions:

   • The AD permits the use of paragraph 2.B. of the named ASBs or “later EASA approved revision[s]”. Before relying on any revised ASB, confirm that the revision is EASA-approved. Document the ASB revision number and approval status in the maintenance record when carrying out the inspection or replacement.

8. Maintain documentary evidence:

   • Record the inspection findings, part numbers replaced, MOD compliance status, dates, flight-hour readings at inspection and replacement, and the ASB revision used. Although the AD does not state record-keeping procedures, these records will be essential to demonstrate compliance with the AD’s exacting references to ASB paragraphs and compliance times.

9. Coordinate with regulatory and supply channels:

   • Liaise with CASA if clarification is required about the AD’s applicability, the interpretation of the calendar deadline, or proof-of-compliance standards. For parts and modifications, coordinate with Eurocopter-approved parts suppliers and maintenance organisations to obtain improved parts and to have MODs performed “in accordance with” the specified ASB revision.

10. Treat the AD as active from the effective date:

• The Amendment became effective on 14 September 2007. Ensure compliance actions are timed accordingly, reconciling any earlier triggers in the AD (for example, the 26 October 2006 reference) with the effective date and aircraft-specific flight-hour data (signature block; “This Amendment becomes effective on 14 September 2007”).

11. Prevent inadvertent installation during future maintenance:

• Update maintenance control documents, parts catalogues and shed-based workshop procedures to block the use of the prohibited part numbers and to ensure that any reinstallation of sliding doors meets the MOD requirements. Train staff and adjust procurement approvals so that prohibited parts cannot be fitted.

12. Monitor for EASA or Eurocopter updates:

• Because the AD allows later EASA-approved revisions of the ASBs, monitor Eurocopter ASB releases and EASA approvals for any revisions that may alter inspection methods, replacement processes, or approved MOD standards.

By following these steps, which are direct translations of the AD’s explicit Requirements and Compliance text into operational actions, operators and maintainers should meet the AD’s obligations. All actions must be documented with reference to the specific ASB paragraph used and the EASA approval status where applicable.