{"id":"F2006B06094","name":"AD/PC-12/31 - Firewall Insulation","slug":"ad-pc-12-31-firewall-insulation","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":46829,"registerId":"commonwealth-F2006B06094-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"AIRWORTHINESS DIRECTIVE","sectionType":"part","heading":"AIRWORTHINESS DIRECTIVE","content":"# AIRWORTHINESS DIRECTIVE\n\n![](image.001.png)\n\n![](image.001.png)  \nFor the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.1 (1) of CAR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.\n\nPilatus PC-12 Series Aeroplanes","sortOrder":0},{"sectionNumber":"AD/PC-12/31 Firewall Insulation 1/2002","sectionType":"part","heading":"AD/PC-12/31 Firewall Insulation 1/2002","content":"# AD/PC-12/31 Firewall Insulation 1/2002\n\nApplicability: All PC-12 and PC-12/45 aircraft with manufacturer’s serial numbers MSN 101 through MSN 399.\n\nRequirement: Action in accordance with the Accomplishment Instructions of Pilatus Aircraft Service Bulletin No.25-023, dated 5 July 2001.\n\nNote: Switzerland FOCA AD HB 2001-636.\n\nCompliance: At the next annual inspection or at next removal of crew seats after 24 January 2002, whichever occurs first.\n\nThis Airworthiness Directive becomes effective on 24 January 2002.\n\nBackground: A report was received of an incident where movement of the aileron flight control system was restricted. It has been found that only the lower edges of the firewall insulation material are secured, and the remaining edges may be free. If free edges of the insulation separate from the firewall, interference with the aileron controls could occur.\n\n![Signature of David Villiers, Delegate of the Civil Aviation Safety Authority.](image.002.png)  \n\nDavid Alan Villiers\n\nDelegate of the Civil Aviation Safety Authority 4 December 2001\n\n![](image.001.png)  \n\nThe above AD is notified in the Commonwealth of Australia Gazette on 9 January 2002.","sortOrder":1}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a targeted safety directive addressing a specific mechanical defect in a specific aircraft model. The scope remains precisely limited to the firewall insulation issue identified in the background section."},"complexity_factors":["Single, clearly defined applicability (specific aircraft serial numbers)","Single requirement referencing an external technical document (Service Bulletin)","Simple compliance deadline (next annual inspection or seat removal)","No defined terms section","No nested exceptions or conditional logic","Straightforward background explaining the safety risk","Total length is approximately one page"],"plain_english_summary":"This CASA Airworthiness Directive requires owners/operators of Pilatus PC‑12 and PC‑12/45 (S/N 101–399) to inspect and secure firewall insulation per Pilatus Service Bulletin No.25‑023 (5 Jul 2001). \n\nThe fix must be done by the next annual inspection or the next crew‑seat removal after 24 Jan 2002. Loose insulation can flap and jam aileron controls, creating a serious flight-safety hazard."},"flash_summary_failed":{"failed":true,"reason":"Unauthenticated. Configure AI_GATEWAY_API_KEY or use a provider module. Learn more: https://ai-sdk.dev/unauthenticated-ai-gateway","source":"analysis-cron"},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The AD remains focused on the original safety issue described in the Background: preventing loose firewall insulation from interfering with aileron controls. It mandates a single corrective action (as set out in the manufacturer’s service bulletin) for a defined subset of PC‑12 aircraft. There is no expansion of scope beyond that original corrective purpose in the text of this AD."},"complexity_factors":["Short, single‑issue AD (limited length)","Narrow applicability (one aircraft family, specific MSN range)","Single external cross‑reference to Pilatus Service Bulletin No.25‑023 (increases dependence on an external technical document)","Simple compliance condition: earliest of next annual inspection or next removal of crew seats after a specified date","No defined term section in the AD itself (low internal definitional complexity)","Reference to an overseas authority’s AD (Swiss FOCA) but no additional harmonisation rules","Clear enforcement mechanism (CASA delegate) with no layered exceptions or sub‑parts"],"plain_english_summary":"**What this instrument does (mechanics first)**\n\n- The Civil Aviation Safety Authority (CASA) requires a specific inspection/repair action on certain Pilatus PC‑12 aeroplanes. The work must be done exactly as set out in the Pilatus Aircraft Service Bulletin No.25‑023 (dated 5 July 2001).\n- It applies to all Pilatus PC‑12 and PC‑12/45 aircraft with manufacturer serial numbers (MSN) 101 through 399 (see “Applicability” section).\n- The work must be completed at the earlier of: the aircraft’s next annual inspection, or the next time the crew seats are removed after 24 January 2002 (see “Compliance” section).\n- The AD became effective 24 January 2002 and was issued by a CASA delegate under subregulation 39.1(1) of CAR 1998 (see header and signature block).\n\n**Why the rule exists (stated rationale)**\n\n- CASA received a report where movement of the aileron flight control system was restricted. Investigation found that the firewall insulation had only its lower edges secured; the other edges could be loose. If those loose edges separate from the firewall they could interfere with the aileron controls. The AD orders the corrective action described by the manufacturer to remove that unsafe condition (see \"Background\" and \"Requirement\").\n\n**Who it affects**\n\n- Owners and operators of Pilatus PC‑12 / PC‑12/45 aeroplanes with MSN 101–399.\n- Maintenance organisations and licensed aircraft engineers who perform annual inspections or remove crew seats on those aircraft.\n\n**Who pays and who decides**\n\n- Aircraft owners/operators bear the cost of the inspection/repair (parts and labour) and any time the aircraft is out of service.\n- Maintenance providers carry out the mandated work, following the manufacturer’s service bulletin instructions.\n- CASA (through its delegate) mandates the requirement and can enforce compliance; the technical method is prescribed by the manufacturer’s Service Bulletin referenced in the AD.\n\n**Behaviour changes required**\n\n- Inspect and, if necessary, secure or replace firewall insulation per Pilatus Service Bulletin No.25‑023 the next time the aircraft has its annual inspection or when crew seats are next removed (after the effective date).\n- Maintenance providers must follow the specific accomplishment instructions in that Service Bulletin.\n\n**Costs, incentives, trade‑offs and implementation issues**\n\n- Direct costs: labour and any parts required to secure or replace firewall insulation; potential short‑term grounding during the inspection/repair window.\n- Opportunity cost: if multiple aircraft cluster at annual inspections, availability and scheduling of maintenance slots could be affected.\n- Compliance burden: low in procedural complexity (single, specific action) but requires reliance on an external document (Pilatus Service Bulletin) for technical detail.\n- Enforcement and discretion: CASA prescribes the corrective action but does not set technical methods itself; maintenance providers must implement the manufacturer’s instructions. CASA retains enforcement authority if the AD is not complied with.\n- Safety benefit vs cost: the AD addresses a specific physical hazard (loose insulation potentially interfering with aileron controls). The cost is limited to targeted inspection/repair on a defined fleet subset.\n- Market effects: minimal—imposes a one‑off or occasional maintenance cost on affected aircraft; maintenance shops perform the work, which could give small, localised business to those providers but does not alter ownership, competition, prices or contractual freedom beyond the imposition of the regulatory maintenance requirement.\n- Implementation risk: effectiveness depends on correct application of the Service Bulletin. Variation in workmanship or failure to follow the bulletin could leave the hazard unresolved.\n\n**Cross‑references and international note**\n\n- The AD references Pilatus Service Bulletin No.25‑023 (5 July 2001) for technical instructions (see “Requirement”).\n- The AD notes the equivalent Swiss FOCA AD HB 2001‑636 (see note).\n\n(Sections cited: Applicability; Requirement; Compliance; Background; signature/effective date.)"}},"importantCases":[],"_links":{"self":"/api/acts/ad-pc-12-31-firewall-insulation","history":"/api/acts/ad-pc-12-31-firewall-insulation/history","analysis":"/api/acts/ad-pc-12-31-firewall-insulation/analysis","conflicts":"/api/acts/ad-pc-12-31-firewall-insulation/conflicts","importantCases":"/api/acts/ad-pc-12-31-firewall-insulation/important-cases","documents":"/api/acts/ad-pc-12-31-firewall-insulation/documents"}}