{"id":"F2006B06265","name":"AD/PL 12/19 - Stub Wing Internal Structure - Inspection and Re-Protection","slug":"ad-pl-12-19-stub-wing-internal-structure-inspection-and-re-protection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":47270,"registerId":"commonwealth-F2006B06265-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/PL 12/19 - Stub Wing Internal Structure - Inspection and Re-Protection","content":"---\nmeta-content-style-type: text/css\nmeta-content-type: application/xhtml+xml; charset=utf-8\nmeta-generator: Aspose.Words for .NET 22.10.0\n---\n\n?xml version=\"1.0\" encoding=\"utf-8\" standalone=\"no\"?>\n\nCOMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n \n\n![](image.001.png)  Transavia PL 12 Series Aeroplanes\n\n \n\nAD/PL 12/19 Stub Wing Internal Structure - Inspection\n\nand Re-Protection\n\n\n7/80\n\n \n\nApplicability: All PL-12 Series. Document:  Transavia SB No. 30.\n\nCompliance: 1. For aircraft which have achieved 3 years time in service since manufacture, initially inspect not later than the next major inspection and thereafter in accordance with SB No. 30.\n\n \n\n2. For other aircraft, initially inspect not later than next major inspection after achieving 3 years time in service after manufacture and thereafter in accordance with SB No. 30.\n\n \n\nBackground:  Corrosion of the interior structure of the steel stub wing has been observed in some aircraft.\n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The directive enforces inspections and re-protection for the stub wing internal structure of all PL-12 series aeroplanes in response to observed corrosion and ties compliance to Transavia Service Bulletin No. 30. The AD does not expand or narrow that stated purpose within the text provided: it prescribes timing rules linked to the 3-year service milestone and the next major inspection and delegates technical detail to the SB. (Applicability; Document; Compliance 1–2; Background)"},"complexity_factors":["Legal form: an airworthiness directive (straightforward mandatory order) rather than complex regulatory reform (Header: Schedule of Airworthiness Directives).","Dependence on an external technical document: Transavia Service Bulletin No. 30 contains the detailed procedures and intervals, so the AD is short but operationally dependent on that SB (Document).","Timing rule linked to an operational milestone (3 years time-in-service) and to scheduled maintenance ('next major inspection'), which requires tracking aircraft age and maintenance schedules (Compliance 1–2).","Scope covers an entire model series (All PL-12 Series), creating a single, uniformly applied obligation but a potentially large number of individual compliance events (Applicability).","Limited technical detail in the AD itself increases operational uncertainty about exact labour, tooling or downtime required until the SB is consulted (Document)."],"plain_english_summary":"What this directive does (mechanically)\n\n- The Civil Aviation Safety Authority requires owners/operators of all Transavia PL-12 series aeroplanes to inspect the internal structure of the steel stub wing and to carry out any re-protection work required by the manufacturer service bulletin. (Applicability; Document; Compliance 1–2)\n\n- For aeroplanes that have already reached 3 years time-in-service since manufacture, the required inspection must be done no later than the next scheduled major inspection and thereafter repeated as specified in Transavia Service Bulletin No. 30. (Compliance 1)\n\n- For aeroplanes that have not yet reached 3 years, the initial inspection must be done no later than the next major inspection after the aeroplane reaches 3 years time-in-service, and thereafter as specified in the service bulletin. (Compliance 2)\n\nWhy the directive was issued (stated purpose)\n\n- The directive cites observed corrosion of the internal structure of the steel stub wing in some aircraft as the reason for the inspections and re-protection requirement. (Background)\n\nWho is affected, who decides, and who pays\n\n- Affected parties: owners and operators of all Transavia PL-12 series aeroplanes. (Applicability)\n\n- The decision to require inspection and re-protection is made by the Civil Aviation Safety Authority under the airworthiness directive regime. (Header: Civil Aviation Safety Authority; Schedule of Airworthiness Directives)\n\n- Who pays: the owner/operator will bear the direct costs of carrying out the inspection and any re-protection work required by Transavia Service Bulletin No. 30 (the AD makes compliance with that SB mandatory; Document; Compliance 1–2). Any costs for parts, labour and downtime arise from complying with the SB's procedures.\n\nHow behaviour and choices change (concrete mechanics)\n\n- Owners/operators must schedule the inspection at the timing set out above (on or after 3 years and by the next major inspection) and must follow the inspection and re-protection procedures in Transavia SB No. 30. (Compliance 1–2; Document)\n\n- Maintenance providers will need access to the stub wing internal structure and to follow the steps in SB No. 30 to complete inspections and any corrosion re-protection work; this channels maintenance work to providers capable of meeting the SB requirements. (Document)\n\nTrade-offs, implementation risks and compliance burdens (source-grounded)\n\n- Compliance burden: the AD creates an ongoing inspection obligation tied to the aircraft's service life and major inspection cycle; that imposes recurring labour, parts and scheduling costs on owners/operators. (Compliance 1–2)\n\n- Dependence on external document: the AD makes Transavia Service Bulletin No. 30 the mandatory technical reference. The SB will determine the specific inspection technique, intervals beyond the initial timing, and the re-protection method; the AD itself does not specify those technical details. (Document)\n\n- Implementation risks and operational impact: inspection and re-protection of an internal steel structure can require disassembly, access arrangements and downtime; those operational impacts arise from following SB No. 30 rather than from the AD text itself. (Document; Background)\n\n- Incentives and substitution effects: the AD increases demand for maintenance services that can perform the SB's procedures; operators may trade off inspection timing against other maintenance work by aligning with the next major inspection as required. (Compliance 1–2)\n\nConcentrated benefits and diffuse costs (source-grounded observation)\n\n- The direct benefit (reduced risk from undetected corrosion) accrues to individual aircraft owners/operators and to safety oversight objectives cited by the regulator. The cost of required inspections and re-protection is concentrated on those same owners/operators through required maintenance actions. (Background; Compliance 1–2)\n\nNet practical effect in one sentence\n\n- All PL-12 aeroplane owners/operators must have the stub wing internal structure inspected by the specified time relative to each aeroplane's 3-year service milestone and must follow Transavia SB No. 30 for repeat inspections and any re-protection work; the AD was issued because internal corrosion has been observed. (Applicability; Document; Compliance 1–2; Background)"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard, narrowly-targeted airworthiness directive addressing a specific corrosion issue in a specific aircraft type. The scope remains tightly focused on the original safety concern without expansion into broader operational or maintenance requirements."},"complexity_factors":["Very short document (approximately 150 words of substantive content)","Only 2 defined compliance pathways based on aircraft age (binary condition)","Single external reference (Transavia SB No. 30) with no nested cross-references","No defined terms section or interpretation provisions","Simple temporal trigger (3 years time in service) with clear subsequent action","No exceptions, exemptions, or conditional sub-clauses"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA). It applies to all **Transavia PL-12 Series aircraft** (a type of agricultural aeroplane).\n\n**What it requires:**\n- Owners and operators must **inspect the internal steel structure of the stub wing** (the short wing section that connects the main wing to the fuselage) for **corrosion** (rust damage).\n- They must also **re-protect** the structure — meaning clean it up and reapply protective coatings to prevent future rust.\n\n**When to do it:**\n- If your aircraft is **3 years old or older**: inspect it no later than the next major maintenance check, then follow the schedule in **Service Bulletin No. 30** (the manufacturer's official maintenance instructions).\n- If your aircraft is **newer than 3 years**: wait until it hits the 3-year mark, then inspect it at the next major check after that, and follow the same ongoing schedule.\n\n**Why it matters:**\nCorrosion has been found in the stub wing's internal steel framework on some aircraft. Left unchecked, this could weaken the wing structure and create a serious flight safety risk. This directive makes the inspection and repair **legally mandatory** — not optional."}},"importantCases":[],"_links":{"self":"/api/acts/ad-pl-12-19-stub-wing-internal-structure-inspection-and-re-protection","history":"/api/acts/ad-pl-12-19-stub-wing-internal-structure-inspection-and-re-protection/history","analysis":"/api/acts/ad-pl-12-19-stub-wing-internal-structure-inspection-and-re-protection/analysis","conflicts":"/api/acts/ad-pl-12-19-stub-wing-internal-structure-inspection-and-re-protection/conflicts","importantCases":"/api/acts/ad-pl-12-19-stub-wing-internal-structure-inspection-and-re-protection/important-cases","documents":"/api/acts/ad-pl-12-19-stub-wing-internal-structure-inspection-and-re-protection/documents"}}