{"id":"F2006B06155","name":"AD/PC-6/50 - Inboard Fuel Tanks Rib Structure","slug":"ad-pc-6-50-inboard-fuel-tanks-rib-structure","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":46962,"registerId":"commonwealth-F2006B06155-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 Porter PC-6 Series Aeroplanes","sortOrder":0},{"sectionNumber":"AD/PC-6/50 Inboard Fuel Tanks Rib Struct","sectionType":"part","heading":"AD/PC-6/50 Inboard Fuel Tanks Rib Structure 3/2003","content":"# AD/PC-6/50 Inboard Fuel Tanks Rib Structure 3/2003\n\nApplicability: Model PC-6 Series aircraft, with serial numbers up to and including MSN 939. Requirement: Action in accordance with Pilatus Aircraft Mandatory Service Bulletin No. 57-002\n\nNote: Switzerland FOCA AD HB 2003-092 refers.\n\nCompliance: For Part A of the Requirement document:\n\nAt the next scheduled maintenance inspection after 20 March 2003 or before 30 June 2003, whichever occurs first.\n\nFor Part B of the Requirement document:\n\nIf Service Bulletin No. 118 is not incorporated, accomplish before 30 September 2003.\n\nThis Airworthiness Directive becomes effective on 20 March 2003.\n\nBackground: Crack damage has occurred in the ribs in the inboard integral fuel tanks in the left and right wings of PC-6 aircraft.\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 6 February 2003\n\n![](image.001.png)","sortOrder":1}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This Airworthiness Directive maintains its original narrow scope: addressing a specific structural defect (cracked fuel tank ribs) in a specific aircraft type. There is no evidence of scope creep; it remains tightly focused on the safety issue identified in the background."},"complexity_factors":["Single, clearly defined applicability (specific aircraft model and serial number range)","Only one primary requirement document referenced (Pilatus Service Bulletin 57-002)","Simple two-part compliance structure with clear calendar deadlines","No defined terms section or interpretation provisions","No nested exceptions or conditional logic beyond basic 'if/then' for Part B timing","Short document (approximately 250 words of substantive text)","Single regulatory basis cited (CAR 1998 subregulation 39.1(1))"],"plain_english_summary":"This CASA Airworthiness Directive orders owners/operators and maintenance organisations of Pilatus Porter PC-6 aircraft (serial numbers up to MSN 939) to inspect wing fuel-tank ribs for cracks and carry out repairs per Pilatus Service Bulletin 57-002. Cracked ribs risk fuel leaks, structural failure or fire. Inspections were required by mid‑2003, and any necessary repairs (if SB118 not previously embodied) by late‑2003 — this is mandatory."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The Directive confines its remit to PC-6 aircraft up to MSN 939 and mandates actions set out in the referenced service bulletin to address discovered rib cracking. The text shows no expansion or contraction of applicability beyond that targeted corrective action."},"complexity_factors":["Relies on external technical document: Pilatus Mandatory Service Bulletin No. 57-002 (required actions not detailed in the AD)","Conditional compliance depends on whether Service Bulletin No. 118 is already incorporated","Applicability limited by serial-number cut-off (MSN up to and including 939)","Multiple discrete compliance deadlines (Part A and Part B with different dates)","Legal provenance specified (issued under subregulation 39.1(1) of CAR 1998) but procedural steps are straightforward"],"plain_english_summary":"This Airworthiness Directive orders owners/operators of Pilatus PC-6 aeroplanes (serial numbers up to and including MSN 939) to carry out the inspections and corrective work set out in Pilatus Mandatory Service Bulletin No. 57-002. It sets a near-term timetable: Part A at the next scheduled maintenance after 20 March 2003 or by 30 June 2003, and Part B by 30 September 2003 unless Service Bulletin No. 118 is already fitted, prompted by reported cracks in the inboard fuel‑tank ribs."},"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"}},"importantCases":[],"_links":{"self":"/api/acts/ad-pc-6-50-inboard-fuel-tanks-rib-structure","history":"/api/acts/ad-pc-6-50-inboard-fuel-tanks-rib-structure/history","analysis":"/api/acts/ad-pc-6-50-inboard-fuel-tanks-rib-structure/analysis","conflicts":"/api/acts/ad-pc-6-50-inboard-fuel-tanks-rib-structure/conflicts","importantCases":"/api/acts/ad-pc-6-50-inboard-fuel-tanks-rib-structure/important-cases","documents":"/api/acts/ad-pc-6-50-inboard-fuel-tanks-rib-structure/documents"}}