{"id":"F2006B06103","name":"AD/PC-12/40 - Flap Flexible Shafts.","slug":"ad-pc-12-40-flap-flexible-shafts","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":46848,"registerId":"commonwealth-F2006B06103-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\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 CASR 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\n![](image.001.png)  \n\nPilatus PC-12 Series Aeroplanes","sortOrder":0},{"sectionNumber":"AD/PC-12/40 Flap Flexible Shafts. 5/2004","sectionType":"part","heading":"AD/PC-12/40 Flap Flexible Shafts. 5/2004","content":"# AD/PC-12/40 Flap Flexible Shafts. 5/2004\n\nApplicability: All PC-12 and PC-2/45 aircraft, MSN 101 through MSN 489, with inboard and/or outboard flap flexible shafts (flexshafts) part numbers 945.02.02.203 and 945.02.02.204 installed.\n\nRequirement: Remove flap flexshafts part numbers 945.02.02.203 and 945.02.02.204 and install new flap flexshafts part numbers 945.02.02.205 and 945.02.02 206; in accordance with Pilatus PC-12 Service Bulletin No. 27-015 Revision A, dated 13 November 2003.\n\nNote: Switzerland FOCA AD HB-2004-068 refers.\n\nCompliance: At the next 100 Hour/Annual Inspection after 13 May 2004, but not later than 13 June 2004; unless already accomplished.\n\nThis Airworthiness Directive becomes effective on 13 May 2004.\n\nBackground: The Manufacturer received several reports of corroded inner drive cables of the flap flexshafts. Investigation revealed that moisture from the pressurised cabin can enter the flap flexshafts at the attachments of the actuators. This condition, if not corrected, could lead to rupture of the flap flexshafts and consequent inoperative flap system.\n\nThis Directive introduces flap flexshafts with improved sealing.\n\n![Signature of David Villiers, Delegate of the Civil Aviation Safety Authority.](image.002.png)  \n\nDavid Villiers\n\nDelegate of the Civil Aviation Safety Authority 2 April 2004\n\n![](image.001.png)","sortOrder":1}],"analysis":{"flash_summary_failed":{"failed":true,"reason":"A positive credit balance is required for all requests, including BYOK, so fallback providers remain available. Add credits at https://vercel.com/d?to=%2F%5Bteam%5D%2F%7E%2Fai%3Fmodal%3Dtop-up to continue.","source":"analysis-cron"},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The directive stays within the original safety purpose: it addresses a specific unsafe condition (corrosion of flap flexshaft drive cables) by mandating replacement with improved-sealed parts. It does not broaden regulation to unrelated components, operations, or aircraft types, nor introduce additional ongoing obligations beyond the one-time mandated replacement and compliance reporting per usual AD practice (Applicability, Requirement, Background)."},"complexity_factors":["Short, single-issue directive focused on one unsafe condition (corroded inner drive cables).","Applicability limited to a single aircraft family and a contiguous range of serial numbers (MSN 101–489).","Only four part numbers involved (two to be removed, two to be installed).","Single external document referenced for procedural detail (Pilatus Service Bulletin No. 27-015 Revision A).","One clear compliance window with a fixed latest date and a simple conditional ('unless already accomplished').","No nested exceptions, no long list of defined terms, and no extensive cross-references to other regulations."],"plain_english_summary":"**What this instrument does (mechanically)**\n\n- Applies to Pilatus PC-12 and PC-2/45 aeroplanes (manufacturer serial numbers 101–489) that have the inboard and/or outboard flap flexible shafts (\"flexshafts\") with part numbers 945.02.02.203 or 945.02.02.204 installed. (Applicability)\n- Requires removal of those flexshafts and installation of replacement flexshafts with new part numbers 945.02.02.205 and 945.02.02.206, following Pilatus PC-12 Service Bulletin No. 27-015 Revision A (Requirement).\n- Must be carried out at the next 100‑hour or annual inspection after 13 May 2004, but no later than 13 June 2004, unless already done (Compliance).\n\n**Who is affected**\n\n- Owners and operators of the specified Pilatus PC-12 and PC-2/45 aircraft (MSN 101–489) that currently have the specified older flexshafts fitted.\n- Maintenance providers and organisations that perform the required removal and installation work.\n\n**Why it matters (safety rationale and mechanism)**\n\n- The manufacturer reported corrosion of the inner drive cables inside the existing flexshafts. Investigation found moisture can enter the flexshafts from the pressurised cabin at actuator attachment points (Background).\n- If the inner drive cable ruptures, the flap system could become inoperative. The directive replaces the affected flexshafts with versions that have improved sealing to prevent moisture ingress and reduce the risk of corrosion and rupture.\n\n**Who pays and who decides**\n\n- Aircraft owners/operators pay for parts, labour and any associated downtime. Maintenance organisations perform and document the work.\n- The Civil Aviation Safety Authority (CASA) — via its delegate — issues and enforces the directive; compliance is mandatory for the affected aircraft.\n\n**Practical implementation details and dependencies**\n\n- The mandatory action is a direct parts replacement; the required procedure is specified by Pilatus Service Bulletin No. 27-015 Revision A (Requirement).\n- Compliance timing is tight: the work must be done at the next scheduled 100‑hour or annual inspection after the effective date, and in any case by 13 June 2004 (Compliance). This limits unscheduled downtime but may concentrate demand for parts and maintenance capacity in a short window.\n- The AD’s effectiveness depends on availability of the replacement parts and capability of maintenance facilities to carry out the installation per the service bulletin.\n\n**Costs, incentives and trade-offs**\n\n- Direct costs: purchase of replacement flexshafts and labour to remove/install them and to document compliance. These are borne by owners/operators (Requirement, Compliance).\n- Operational trade-offs: scheduling the replacement during the short compliance window may cause minor scheduling delays or require diversion of maintenance slots. That is an opportunity cost for operators and maintenance providers.\n- Incentives: operators have a clear safety and regulatory incentive to comply within the deadline; non‑compliance would leave an identified unsafe condition uncorrected and could expose operators to regulatory action.\n\n**Implementation risk and potential unintended effects**\n\n- If replacement parts are in short supply, some operators could experience delays beyond the intended compliance window unless CASA provides relief — the AD as written does not provide alternative relief mechanisms.\n- Work quality depends on adherence to the referenced service bulletin; inconsistent maintenance practices could lessen the intended safety benefit.\n\n**Source claims and testing**\n\n- The directive’s stated purpose is to correct an unsafe condition (corroded inner drive cables allowing rupture of flexshafts) by installing parts with improved sealing (Background, Requirement). Mechanically, the AD carries out that purpose by mandating part replacement and specifying the method (service bulletin). The concrete costs and implementation burdens are maintenance time, parts cost and possible scheduling impacts, borne by operators and maintenance organisations (Requirement, Compliance)."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a specific, targeted safety directive addressing a known mechanical defect in a particular aircraft model. The scope remains precisely limited to the identified unsafe condition and the required corrective action. There is no evidence of scope creep or expansion beyond the original safety purpose."},"complexity_factors":["Single, clearly defined applicability (specific aircraft serial numbers and part numbers)","One straightforward requirement (replace specific parts with new part numbers)","Single compliance deadline with simple exception clause ('unless already accomplished')","No cross-references to other legislation (only references to manufacturer service bulletin and Swiss equivalent directive, which are informational)","No defined terms section — all technical terms are either self-explanatory or standard aviation terminology","Short document (approximately 250 words of substantive text)"],"plain_english_summary":"This CASA safety order mandates owners/operators of Pilatus PC‑12 aircraft (MSN 101–489) to replace existing flap flexible shafts (P/N ending 203/204) with improved, better‑sealed versions (P/N ending 205/206). Moisture can enter the shafts, corroding drive cables and risking flap failure on landing. The replacement must be done by the next routine inspection after 13 May 2004, and no later than 13 June 2004. Non‑compliance grounds the aircraft from legal flight."}},"importantCases":[],"_links":{"self":"/api/acts/ad-pc-12-40-flap-flexible-shafts","history":"/api/acts/ad-pc-12-40-flap-flexible-shafts/history","analysis":"/api/acts/ad-pc-12-40-flap-flexible-shafts/analysis","conflicts":"/api/acts/ad-pc-12-40-flap-flexible-shafts/conflicts","importantCases":"/api/acts/ad-pc-12-40-flap-flexible-shafts/important-cases","documents":"/api/acts/ad-pc-12-40-flap-flexible-shafts/documents"}}