AD/DH 60/10 - Inspection of Wooden Structure

Scope and applicability. The AD applies to "all variants of DH 60 aircraft" (Applicability). That broad phrase is the legal scope as written; there is no carve‑out for modified airframes, restorations, or derivative models in the text. The AD defines two shorthand terms: "DHSL" means de Havilland Support Ltd and "TNS" means DHSL Technical News Sheet CT (Moth) No. 32, Issue 3, dated 1 December 2008 (Definitions).

Three core mandatory actions. The Requirements section sets out three mandatory obligations. Requirement 1: suspend all aerobatic flight. Requirement 2: unless previously accomplished, (a) install inspection rings and drainage provisions as per Figure 3 of Appendix G of the TNS; (b) gain access to the internal structure by removing all 'pop-in' panels or by cutting away fabric from inside inspection rings to facilitate access to the entire internal wooden structure; (c) perform a detailed inspection per the inspection criteria at Appendix B paragraph 6 and taking into account Appendix F page F1 paragraph 2 of the TNS; and (d) remove or repair all unserviceable wooden structure in accordance with approved data. Requirement 3: report all defects discovered to CASA via the Service Difficulty Reporting System.

Timing, categories and repeat inspections. The Compliance part sets precise timing. Requirement 1 must be complied with within two weeks of the AD's effective date. Requirement 2 must be done within two months for aircraft used for commercial purposes as prescribed in regulation 206 of the Civil Aviation Regulations 1988, and by 31 December 2015 for all other aircraft. Requirement 2's inspections must be repeated at the earlier of (i) every 200 hours, (ii) within 36 months of the previous inspection, or (iii) after a ground strike, birdstrike or other wing strike of sufficient magnitude to leave witness marks on the fabric, or obvious damage to a wing; in such event, both top and bottom wings are to be inspected on the impacted side. Requirement 3 follows Part 4B - Defect Reporting of CAR 1988.

Technical reliance on an external TNS. The AD anchors its inspection standards and the installation figure to a specific DHSL Technical News Sheet (CT (Moth) No. 32, Issue 3, dated 1 December 2008). It cites three internal parts of the TNS: Appendix G Figure 3 (installation of inspection rings and drainage), Appendix B paragraph 6 (Inspection Content) and Appendix F page F1 paragraph 2 (areas for specific inspections). The AD therefore transfers substantive technical content to that TNS document; the AD itself prescribes actions but delegates the technical inspection content to the TNS.

Operational consequence for aerobatic flight. Aerobatic flight is suspended immediately under the AD until the airworthiness of the wooden structure of the wings and empennage has been established "in accordance with Requirement 2 of this AD." The AD ties operational permission (aerobatics) directly to maintenance/inspection outputs.

Document provenance and authority. The AD is dated and signed by a CASA delegate (Nicholas Ward, 2 February 2015) and the effective date cited is 6 February 2015. The AD’s ID is AD/DH 60/10, Issue 3/2015. The Background section states the AD "will mandate" these inspections to ensure continued airworthiness. Those are the AD’s own explanatory words, not independent findings.

Standards of repair and documentation. Repairs to removed unserviceable wooden structure must be "in accordance with approved data" (Requirement 2(d)). Reporting is through CASA's Service Difficulty Reporting System and referenced to Part 4B - Defect Reporting of the CAR 1988 (Requirement 3 and Compliance references). The AD therefore places obligations on operators to use approved repair data and to record and report defects to the regulator.

Triggers for unscheduled inspection. The AD defines clear event triggers that require inspection: ground strikes, birdstrikes or other wing strikes that leave witness marks on fabric or obvious wing damage require inspection of both top and bottom wings on the side affected. That introduces a safety-critical post-event inspection obligation that is distinct from the scheduled 200-hour/36-month repeat intervals.

Aircraft owners and operators. The AD applies to all variants of DH 60 aircraft, so the primary parties affected are registered owners, operators and any maintenance organisations responsible for those aircraft. The AD makes distinctions in timing between aircraft used for commercial purposes under regulation 206 of the Civil Aviation Regulations 1988 and other aircraft; therefore commercial operators face an earlier compliance deadline (within two months of the effective date) while non-commercial operators had until 31 December 2015 (Compliance). That timing difference directly affects the scheduling burden for commercial operators, who must implement inspection rings, drainage, and detailed inspections sooner.

Pilots and aerobatic operators. All pilots who conduct aerobatic flying in DH 60 variants are directly affected. Aerobatic flight is suspended under Requirement 1 and may only recommence once the airworthiness of the wooden structure of the wings and empennage is established under Requirement 2. Owners who permit aerobatics must therefore ensure inspections and corrective actions are completed before resuming those operations.

Maintenance and repair organisations. Maintenance organisations and certificated engineers are affected by the AD’s substantive maintenance requirements. Requirement 2(d) requires removal of unserviceable wooden structure or repair "in accordance with approved data." That directs maintenance shops to use approved repair data in completing remedial work. The AD also requires installation of inspection rings and drainage provisions per a specified figure in the DHSL TNS (Appendix G Figure 3), so the technical instructions in the external TNS will drive the maintenance tasking.

Regulator and reporting channels. CASA is the recipient of the defect reports. Requirement 3 mandates that all defects discovered be reported to CASA via the Service Difficulty Reporting System, and the Compliance section points to Part 4B - Defect Reporting of CAR 1988. This places a data collection obligation on operators and maintenance providers to submit defects through CASA’s specified mechanism.

Insurers and commercial stakeholders. While the AD does not mention insurers, practical consequences include that insurers underwriting DH 60 operations will face changed risk profiles and may demand compliance evidence. Commercial operators who provide passenger flights, training, or charter services using DH 60 aircraft must meet the earlier two-month deadline, so commercial contracts, availability and scheduling will be affected.

Owners of restored or modified airframes. The AD applies to "all variants" , the text contains no explicit carve-outs for restored, replica or heavily modified DH 60 airframes. Entities that operate modified DH 60 variants must therefore treat the AD as applicable, subject to any approvals or exemptions not contained in the AD text. Compliance will typically require close work with maintenance engineers and, where necessary, with CASA to determine whether particular modifications affect applicability.

Third-party parts and component suppliers. Suppliers of inspection rings, drainage fittings, fabric repair materials and approved repair data may see demand. The AD dictates that inspection rings and drainage provisions be installed per the TNS, and repairs be carried out using approved data; therefore suppliers participating in such work will be engaged under the maintenance programmes implemented to comply.

Passengers and the flying public. Passengers and customers of operators offering aerobatic rides or other services using DH 60 aircraft may experience cancellations, deferrals or reduced availability until the inspections and any remedial work are completed and documented per Requirement 2. The AD ties the resumption of aerobatic operations to the satisfactory establishment of airworthiness of wings and empennage.

Administration and record-keepers. The AD introduces recurrent inspection cycles (every 200 hours or 36 months, whichever is earlier) and post-event inspections; this imposes record-keeping and scheduling burdens on operators or their maintenance managers to ensure that no inspection interval is missed and that records are available to show compliance and to inform defect-reporting obligations.

Expressed duties in the AD. The AD sets discrete duties. Duty 1: suspend all aerobatic flight and implement that suspension within 2 weeks of the effective date (Compliance). Duty 2: install inspection rings and drainage provisions in accordance with Figure 3 of Appendix G of the DHSL TNS; gain access to internal wooden structure by removing 'pop-in' panels or cutting fabric from inside inspection rings; perform detailed internal inspections according to Appendix B paragraph 6 and Appendix F page F1 paragraph 2 of the TNS; and remove or repair all unserviceable wooden structure using approved data (Requirement 2). Duty 3: report all defects discovered to CASA via the Service Difficulty Reporting System, with the reporting requirement aligned to Part 4B - Defect Reporting of CAR 1988 (Requirement 3 and Compliance). Duty 4: repeat Requirement 2 inspections at the earlier of every 200 hours, within 36 months, or after relevant strikes (Compliance).

Timing duties. The AD imposes timing duties with different deadlines depending on the nature of the operation: Requirement 1 within two weeks of the effective date; Requirement 2 within two months for aircraft used commercially under CAR 1988 reg 206 and by 31 December 2015 for others. Repetition frequencies are stated in the Compliance section and form ongoing duties.

Standards/quality control duties. Repairs must be conducted "in accordance with approved data" (Requirement 2(d)). The AD also calls for compliance with the specified inspection content and areas for inspection outlined in the TNS. Those references impose a quality standard that requires access to and application of the TNS content, and adherence by maintenance personnel to its figures and appendices. The AD therefore delegates technical standards to an external technical news sheet, and duty-holders must use that external material to meet the AD’s requirements.

Reporting duty and pathway. The AD requires reporting to CASA via the Service Difficulty Reporting System and directs compliance with Part 4B - Defect Reporting of CAR 1988. The duty to report defects is explicit; the AD does not specify whether minor defects that are repaired immediately must be separately reported beyond the generic instruction to "report all defects discovered." Conformance with Part 4B would govern the detailed reporting format and timing, but the AD itself fixes the duty to report to CASA.

Operational constraint and conditional right to resume aerobatics. The AD creates a conditional right: aerobatic flying may only be recommenced when the airworthiness of the wooden structure of the wings and empennage has been established per Requirement 2. That is not framed as a permission given by CASA in the AD, but as an operational precondition embedded in the AD text; operators therefore must ensure the inspection and any rectification work satisfy the AD’s criteria before resuming aerobatics.

Discretion and approval requirements. The AD requires repairs "in accordance with approved data." It does not define what constitutes approved data in the AD text itself; however, that phrase imposes a duty to use repair data with regulatory acceptance (for example, approved by an appropriate authority or holder). The AD also references specific items of the TNS; operators thus have limited discretion to deviate from the TNS unless alternative approved data is available and used for repairs or inspection procedures. The AD does not specify a process for obtaining relief or alternative compliance within the document text.

Who decides compliance and evidence. The AD places the onus on operators/inspectors to carry out the inspections and repairs and to report defects to CASA. The evidence that aerobatic flight may resume is the establishment of airworthiness of wing and empennage "in accordance with Requirement 2." The AD does not provide a formal clearance mechanism in its text, meaning operators will need to document work via maintenance records, use approved data, and rely on CASA’s regulatory framework for acceptance and oversight.

Interplay with commercial classification. The AD uses regulation 206 of CAR 1988 to distinguish commercial operators for the purpose of an earlier deadline. Duty-holders must therefore determine whether their operations fall within the commercial category under reg 206 to know whether the two-month deadline applies. That is a compliance determination tied to an external regulatory definition.

Mandate and regulatory source. The AD is issued by the Civil Aviation Safety Authority and sets mandatory maintenance and reporting obligations. It references Part 4B - Defect Reporting of the Civil Aviation Regulations 1988 (Requirement 3 and Compliance) and regulation 206 of CAR 1988 for the commercial operator distinction. The AD itself is an instrument that requires compliance with its stated requirements and timings; it is signed by a CASA delegate (Nicholas Ward) and lists an effective date of 6 February 2015.

Enforcement language in the AD. The AD text does not itself specify monetary penalties, licence suspensions, or criminal sanctions in the body of the document. It mandates actions and cross-references CAR 1988 for reporting, but provides no express list of enforcement measures or penalty amounts in the AD as provided. The AD therefore sets obligations that are enforceable as regulatory requirements in the CASA framework, but does not detail enforcement procedures in the text.

Reporting obligation as an enforcement gateway. The AD requires reporting of all defects to CASA via the Service Difficulty Reporting System, and ties that duty to Part 4B of the CAR 1988. Reporting obligations create regulatory visibility and are often the first step that enables subsequent regulatory follow-up. While the AD does not state enforcement actions, the defect reporting requirement channels information to CASA and thereby creates an evidentiary record that CASA can use under its supervisory remit.

Implied enforcement through operation restrictions. The suspension of aerobatic flight is an operational prohibition in the AD. The AD conditions the resumption of aerobatic activity on completion of the inspection and verification required by Requirement 2. Operators who continue to conduct aerobatics without meeting the AD’s requirements would be non-compliant with the directive as written; while the AD does not set out the enforcement mechanism in detail, non-compliance with an AD typically exposes operators to regulatory scrutiny under CASA’s powers and the broader CAR framework referenced in the AD.

No AD-specified penalty amounts in the text. The AD as supplied does not specify fines or enforcement actions or give a sanction table. The AD references CAR 1988 provisions but stops short of including penalty provisions within its own text. Any enforcement steps or penalties available to CASA will therefore derive from the broader regulatory framework of the Civil Aviation Regulations and CASA’s statutory powers, not from penalty clauses in this AD.

Administrative oversight and evidence. Compliance will be demonstrated through maintenance records, the installation of inspection rings/drainage as per the TNS figure, inspection reports following the TNS criteria, and service difficulty reports submitted to CASA. These records are the probable focal point for any enforcement or compliance audit, since the AD supplies specific procedural steps and cross-references the TNS for technical criteria.

Delegation and signatory authority. The AD is signed by a CASA delegate (Nicholas Ward). The presence of a delegate’s signature is an administrative fact establishing CASA’s issuance of the AD; the AD does not itself outline the internal delegation of enforcement powers, but the signature authenticates the instrument.

References to the Civil Aviation Regulations 1988. The AD explicitly references the Civil Aviation Regulations 1988 (CAR 1988) in two places. First, the Compliance timing uses regulation 206 of CAR 1988 to identify aircraft used for "commercial purposes" and applies a shorter compliance timetable to those aircraft (Compliance). Second, Requirement 3's reporting obligation is to be performed "in accordance with Part 4B - Defect Reporting of CAR 1988" (Requirement 3 and Compliance). The AD therefore expressly ties its obligations into classification and reporting provisions of the CAR 1988.

Delegation to a technical news sheet. The AD delegates technical inspection content and installation figures to an external de Havilland Support Ltd Technical News Sheet CT (Moth) No. 32, Issue 3, dated 1 December 2008. The AD requires operators to follow specified appendices and figures within the TNS (Appendix G Figure 3 for inspection rings and drainage; Appendix B paragraph 6 for inspection content; Appendix F page F1 paragraph 2 for areas for specific inspections). That creates a cross-reference link between a CASA AD and manufacturer/maintenance guidance; in practice compliance requires accessing and following that TNS. The AD effectively imports the TNS's technical detail into the regulatory requirement.

"Approved data" and maintenance law. Requirement 2(d) requires removal of unserviceable wooden structure or repairs "in accordance with approved data." The AD does not define "approved data" within its text, but that phrase invokes existing maintenance approval regimes in civil aviation law where certain repair methods and data must be approved by the authority or by an approved organisation. Operators must therefore reconcile the AD’s repair requirement with applicable approval processes under the CAR and CASA’s maintenance approvals.

Operational rules and airworthiness interplay. The AD suspends aerobatic flight and conditions resumption on meeting the prescribed inspections and repairs. That operational requirement will interact with the operators’ obligations under operational regulations and their airworthiness directives. The AD provides a maintenance/airworthiness condition that directly affects operational authorisations: aerobatic permission is linked to demonstrated airworthiness in accordance with the AD.

Reporting channel interaction. The AD’s requirement to report defects via CASA’s Service Difficulty Reporting System and in conformity with Part 4B means the AD’s data flow and oversight are integrated into the CAR 1988 reporting framework. That creates an interface between on-aircraft maintenance work and the regulator’s incident and defect database, enabling CASA to use its statutory reporting regime to monitor compliance and trends.

No express conflict or exemption text. The AD does not contain provisions that expressly override other laws or regulations, nor does it include exemptions, variances or transitional provisions other than the deadlines stated. The AD does not purport to amend the CAR 1988; it references the CAR for classification and reporting. Where an operator needs to reconcile the AD with other regulatory obligations (for example, alternate airworthiness requirements, permits, or existing approvals), the AD’s text does not state a preferred resolution mechanism other than compliance with the AD and the use of approved data for repairs.

Practical dependency on external documents. Compliance requires access to TNS CT (Moth) No. 32 Issue 3 (1 December 2008). The AD’s cross-references to specific appendices and figures import that external document as a practical element of the regulatory requirement. Any interaction questions about the TNS’ content versus other maintenance manuals or repair schemes will require examination of the TNS and any approvals for alternative data , such matters are not resolved inside the AD text.

Single-issue record visible in the source. The AD is identified as AD/DH 60/10 and is labelled 3/2015. The effective date given in the Compliance section is 6 February 2015, and the instrument text bears the signature of a CASA delegate dated 2 February 2015. The document as provided does not list prior AD versions, subsequent amendments, revocations, or consolidated amendment dates within the text.

References inside the AD to external TNS issue date. The AD references DHSL Technical News Sheet CT (Moth) No. 32, Issue 3, dated 1 December 2008 as the technical standard to be followed for installation and inspection content. That TNS issue date is part of the AD’s technical provenance, but the AD does not state that the TNS has been amended or that later TNS issues are acceptable. The AD therefore binds operators to the TNS Issue 3 dated 1 December 2008 as the technical reference in the instrument text.

No amendment clauses in the provided text. The AD text supplied does not include an explicit amendment clause, review date, or sunset clause beyond the inspection frequencies and deadlines it sets. There is no in-text record of amendment history, no stated revocation procedure and no transitional modifications noted in the document excerpt provided.

Administrative signature and issuance date. The AD is signed by a CASA delegate, Nicholas Ward, on 2 February 2015 and lists an effective date of 6 February 2015. That shows the AD’s issuance and commencement details but does not constitute an amendment history.

No statutory amendment to CAR 1988 recorded in the AD. The AD references the Civil Aviation Regulations 1988 (regulation 206 and Part 4B) for classification and reporting. The AD itself does not purport to amend those regulations, nor does it provide an amendment history showing interaction beyond cross-reference. Any change to the CAR 1988 that might affect the AD would not be recorded in this AD text.

Records in the document constitute the available history. For the purposes of understanding amendment history from this source, the only recorded administrative actions are the AD’s issuance details (ID AD/DH 60/10, Issue 3/2015) and the effective date. The AD does not document prior or subsequent amendments, and the text contains no annexed amendment log.

No litigation or judicial decisions are recorded in the instrument text. The AD contains no references to court or tribunal proceedings, no citations of legal challenges, and no mention of appeals or disputes arising from the AD. The AD is an administrative directive issued by CASA and the text supplied does not report any litigation, stays, injunctions, or reviews relating to this AD.

No judicial or tribunal precedent is asserted in the AD. The AD’s background and requirements make safety and inspection claims but do not cite case law or litigation outcomes as factual bases. The document is purely administrative in nature and the supplied text contains no litigation history or references to contested proceedings.

If litigation exists outside the text. The AD does not provide any external litigation summary or pointer. Any assertion of litigation must be sourced from materials beyond the AD itself. The AD as supplied should be treated as not containing any litigation history; readers seeking litigation records would need to consult judicial databases, tribunal records or CASA enforcement logs outside the AD text.

Enforcement or dispute mechanisms not described in text. The AD invokes CAR 1988 provisions for reporting and operator classification, but it does not describe dispute resolution mechanisms or appeal rights in the text provided. Any enforcement actions, reviews or appeals involving this AD are therefore not recorded within this document.

Reliance on an external TNS creates a practical compliance dependency. The AD requires specific installations and inspection content "in accordance with" particular appendices and figures of DHSL Technical News Sheet CT (Moth) No. 32 Issue 3 (Requirement 2 references Appendix G Figure 3, Appendix B paragraph 6, and Appendix F page F1 paragraph 2). Operators must obtain and apply that TNS. Failure to access, retain or correctly interpret the specified TNS material risks non-compliance even where inspections are conducted. The AD imports external technical detail into regulatory obligations rather than setting all technical specifics within the AD itself.

Timing differentials between commercial and non-commercial operators. The AD imposes a two-month deadline for aircraft used for commercial purposes as defined by regulation 206 of CAR 1988, and a later deadline (by 31 December 2015) for other aircraft. Operators must determine their classification under reg 206 to know which deadline applies. Misclassification or misunderstanding of the scope of reg 206 could lead to missed earlier deadlines for commercial operators.

Immediate suspension of aerobatics with a tight deadline. Requirement 1 must be actioned within two weeks of the effective date (Compliance). Aerobatic flight cannot restart until the airworthiness of wings and empennage is established per Requirement 2. That two-week immediate prohibition can materially affect revenue for operators offering aerobatic flights and requires quick scheduling of inspections, particularly if parts or skilled labour are constrained.

Invasive access methods may cause additional work. Requirement 2(b) permits gaining access to internal structures "by removing all 'pop-in' panels, or otherwise cut away the fabric from inside inspection rings to facilitate access to the entire internal wooden structure." Cutting away fabric from inside inspection rings is an invasive step that may itself require further repair, re-covering, or re-fabric work to restore the aircraft to its prior cover standard. The AD mandates repair or removal of unserviceable wood and repair "in accordance with approved data" (Requirement 2(d)), but operators must budget time and cost for additional fabric work that may be uncovered as necessary when access is gained.

Repetition intervals may be operationally disruptive. The AD requires repeating Requirement 2 inspections at the earlier of every 200 hours or within 36 months. For aircraft used intensively, a 200-hour interval could necessitate frequent significant inspections. Operators must schedule maintenance slots and consider aircraft downtime, potentially affecting revenue or availability.

Post-impact inspection obligations may broaden scope of work. The AD requires inspections after ground strikes, birdstrikes, or other wing strikes that leave witness marks or obvious damage, and states that in such events both top and bottom wings are to be inspected on the side of the aircraft where the impact occurred. That could expand inspection scope beyond the immediate area of visible damage and create unexpected maintenance demands after relatively minor incidents that nonetheless leave witness marks on the fabric.

"Approved data" vagueness. Repairs must be "in accordance with approved data" (Requirement 2(d)). The AD provides no definition of "approved data" within its text. In practice, "approved data" will implicate maintenance approval regimes, engineering approvals and possibly CASA acceptance. Operators should clarify, with maintenance providers or CASA, whether particular repair schemes or alternative technical data meet the "approved data" requirement before proceeding.

Reporting requirement scope. The AD requires "Report all defects discovered to CASA via the Service Difficulty Reporting System" (Requirement 3). It does not distinguish between defects corrected on the spot and defects that remain outstanding. Operators should not assume that minor, immediately fixed issues are exempt from reporting; the AD's language is broad and ties the obligation to Part 4B of the CAR 1988.

Applicability to all variants. The AD applies to "all variants of DH 60 aircraft" (Applicability). That broad applicability can catch modified or restored airframes unless those aircraft have explicit approvals documenting otherwise. Operators of non-standard variants should not assume exemption and should seek confirmation if there is any doubt.

No penalties set out in the AD text. The AD does not include explicit penalty provisions or enforcement steps in the document as provided. That does not mean failure to comply is without consequence; rather, compliance will be assessed and enforced through CASA’s broader regulatory powers. Operators should not interpret the absence of penalty language as lack of enforcement risk.

Record-keeping and proof. Because the AD ties operational permission (aerobatics) to established airworthiness via Requirement 2, operators need to retain clear, auditable maintenance records demonstrating compliance with the TNS-referenced inspection content and any repairs performed using approved data. Lack of documentary proof could cause regulators to treat aerobatic permission as not having been restored.

Immediate actions (within two weeks of effective date). Implement Requirement 1 by suspending all aerobatic flight. Do this within the two-week window mandated by the Compliance section. Document the operational suspension in an operations record so there is contemporaneous evidence of compliance. Aerobatic activity may not resume until the airworthiness of the wooden structure of the wings and empennage has been established in accordance with Requirement 2.

Obtain the referenced technical material. Secure a copy of DHSL Technical News Sheet CT (Moth) No. 32, Issue 3, dated 1 December 2008. The AD requires installations and inspections "in accordance with" specific appendices and figures in the TNS (Appendix G Figure 3, Appendix B paragraph 6, Appendix F page F1 paragraph 2). Compliance requires reading and applying those parts of the TNS.

Plan the main inspection and installation per deadlines. For commercial operators as defined by CAR 1988 reg 206, schedule and complete Requirement 2 within two months of the AD’s effective date. For other operators, complete Requirement 2 by 31 December 2015. This includes: (a) installing inspection rings and drainage provisions as per Figure 3 of Appendix G of the TNS; (b) gaining access to internal wooden structure by removing pop-in panels or cutting fabric from inside inspection rings; (c) performing a detailed inspection consistent with Appendix B paragraph 6 and considering Appendix F page F1 paragraph 2 of the TNS; and (d) removing or repairing unserviceable wood using approved data.

Use approved maintenance personnel and approved data. Ensure maintenance work is carried out by appropriately authorised certificated engineers or maintenance organisations. Repairs must be completed "in accordance with approved data" (Requirement 2(d)). Confirm with your maintenance organisation what constitutes approved data for the required repairs and whether CASA acceptance or approval is required for any alternative repair schemes.

Prepare for invasive work and subsequent finishing. Where the inspection process requires cutting fabric, plan for subsequent fabric restoration or re-covering work as necessary. Budget time and parts for any re-covering, rigid or flexible patching, and sealing consistent with the approved data used for repairs.

Repeat inspection scheduling and logging. Implement and track the repeat inspection requirement: schedule repeat inspections at the earlier of every 200 flight hours or within 36 months of the previous inspection. Maintain accurate flight-hour logs to determine when 200 hours occurs and monitor the three-year calendar interval. Include post-event inspection triggers in operational procedures: after any ground strike, birdstrike or other wing strike that leaves witness marks or obvious damage, inspect both top and bottom wings on the side of impact.

Post-impact inspection procedure. Adopt a procedure whereby any event likely to leave witness marks causes an immediate inspection per the AD. The AD requires inspection of both top and bottom wings on the side of the aircraft where the impact occurred. Ensure that maintenance teams are available or contactable to perform those inspections in a timely fashion.

Defect reporting procedures. Establish internal rules to ensure any defects discovered during inspections are reported to CASA via the Service Difficulty Reporting System in accordance with Part 4B - Defect Reporting of CAR 1988 (Requirement 3). Keep records of all Service Difficulty Reports submitted and cross-link them to maintenance records showing rectifications and any approved data used.

Document evidence that aerobatics may resume. Since aerobatic flight may only recommence once the airworthiness of the wooden structure of wings and empennage is established under Requirement 2, compile and retain documentation that demonstrates compliance with Requirement 2: installation of inspection fittings per the TNS, inspection reports showing the inspection content at Appendix B paragraph 6 and Appendix F page F1 paragraph 2, records of removed/ repaired wood with references to the approved data used, and evidence of reporting to CASA of any defects discovered.

Coordinate with insurers and customers. Notify insurers where required and communicate with customers about expected downtime where inspections are scheduled. For commercial operators, schedule slots to meet the faster two-month deadline and consider contingency aircraft or timetable adjustments to maintain operations.

Clarify "approved data" before repairs. Before performing repairs, confirm with the maintenance organisation and, if necessary, with CASA what constitutes "approved data" for the particular repair. If using data that departs from the TNS, secure documented approval or acceptance as necessary to avoid later compliance questions.

Maintain administrative records and audit readiness. Keep a clear audit trail tying each action to the AD: the date aerobatic activities were suspended, dates of installation of inspection rings/drainage, inspection reports referencing the TNS appendices and paragraphs, details and authorisation of any repair using approved data, and copies of Service Difficulty Reports filed with CASA. These records are the primary evidence for any regulatory review.

Engage CASA proactively if in doubt. The AD references external material and statutory classifications (CAR 1988 reg 206, Part 4B). If there is any uncertainty about classification, alternative approved data, or the adequacy of proposed repairs, consult CASA or seek written clarification before resuming aerobatic operations or declaring compliance.

Plan staffing and parts procurement. The required work may need specific parts (inspection rings, drainage fittings) and skilled labour familiar with wooden-structure inspection and fabric covering techniques. Order parts and schedule qualified maintenance resources in advance so that compliance deadlines, especially for commercial operators, can be met.

Implement routine training for inspection recognition. Ensure maintenance personnel know the inspection criteria from Appendix B paragraph 6 and Appendix F page F1 paragraph 2 of the TNS so inspections are consistent and aligned to the AD’s referenced criteria. Standardise inspection reporting templates to ensure all required data points are captured and can be reported to CASA as necessary.

Track and manage recurring obligations. Create an inspection schedule with alerts tied to both flight hours and calendar time to ensure inspections occur at the earlier of every 200 hours or within 36 months. Include post-impact triggers in the same schedule so that any incident prompts a documented inspection without delay.

In summary, compliance requires immediate operational adjustments, sourcing and using the specified TNS material, scheduling and performing intrusive inspections and installations, using approved repair data, reporting defects to CASA, and instituting record-keeping and scheduling systems to meet recurrent obligations.