{"id":"F2006B11192","name":"AD/LYC/100 - Piston Pin P/N LW-14077","slug":"ad-lyc-100-piston-pin-p-n-lw-14077","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":56899,"registerId":"commonwealth-F2006B11192-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/LYC/100 - Piston Pin P/N LW-14077","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 106 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nLycoming Piston Engines\n\nAD/LYC/100 Piston Pin P/N LW-14077 1/97\n\nApplicability: 1. All Textron Lycoming piston engines as detailed by model and serial number in Textron Lycoming Service Bulletin (SB) Number 527B.\n\nNote 1: Applicable engines were released by Textron Lycoming in the period 15 December 1995 to 17 September 1996.\n\n    2. All Textron Lycoming piston engines in service which have had piston pins part number (P/N) LW-14077 installed since 15 December 1995.\n\n    3. All cylinder kits applicable to Textron Lycoming piston engines, regardless of the cylinder manufacturer.\n\n    4. Textron Lycoming piston pins P/N LW-14077 released by Textron Lycoming in the period 15 December 1995 to 17 September 1996.\n\nRequirement: Remove from service all piston pins P/N LW-14077 which are marked with the code 17328.\n\nNote 2: Lycoming SB No. 527B details procedures in which the piston pin may be identified without removing the cylinder.\n\nCompliance: Applicability 1: Within 50 hours time in service after 2 January 1997.\n\nApplicability 2: Within 50 hours time in service after 2 January 1997\\. Applicability 3: Prior to installation in an aircraft.\n\nApplicability 4: Prior to installation in an aircraft.\n\nBackground: This directive has been issued to require certain piston pins to be removed from service. The requirement follows advice from the manufacturer that a quantity of piston pins released since 15 December 1995 do not meet the manufacturer’s specifications. The failure of a piston pin in service may result in engine failure.","sortOrder":0}],"analysis":{"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 directive implements the manufacturer's reported concern by targeting LW-14077 piston pins released since 15 Dec 1995 (Background; Applicability 4) and those installed since that date (Applicability 2), and extends the removal/installation prohibition to cylinder kits (Applicability 3). This aligns with the stated safety remediation objective and does not expand the remedy beyond removing the identified defective pins and preventing their installation."},"complexity_factors":["Targeted, single-component remedy (Requirement: remove pins P/N LW-14077 marked 17328) — narrow technical focus reduces complexity.","Multiple applicability categories covering: listed engine models/serials (Applicability 1), any in-service engine with the part installed since 15 Dec 1995 (Applicability 2), all cylinder kits (Applicability 3), and pins released in a specific date range (Applicability 4) — increases scope-tracking burden.","Different compliance triggers and deadlines: 50 hours TIS after 2 Jan 1997 for in-service items, and ‘prior to installation’ for kits and released pins (Compliance) — procedural complexity for scheduling inspections/maintenance.","Identification requirement referencing manufacturer SB No. 527B which allows identification without cylinder removal (Note 2) — reliance on external technical procedure for compliance.","Dependence on manufacturer release dates and part marking (Background; Applicability 4) — requires record checks and physical marking verification.","No explicit enforcement or penalty mechanisms stated in the text — potential implementation discretion lies with regulators/operators."],"plain_english_summary":"This directive orders removal of Lycoming piston pins P/N LW-14077 that are marked with code 17328. It applies to the Textron Lycoming engines listed in Service Bulletin 527B, any engines fitted with those pins since 15 Dec 1995, and to all cylinder kits; identified pins must be removed within 50 hours TIS after 2 Jan 1997 or before installation. The measure follows manufacturer advice that some pins released between 15 Dec 1995 and 17 Sep 1996 did not meet specification."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a targeted safety directive addressing a specific manufacturing defect in a specific part. The scope remains precisely limited to the identified faulty piston pins and has not expanded beyond this original safety purpose."},"complexity_factors":["Single, specific mechanical part targeted (piston pin P/N LW-14077)","Only one substantive requirement: remove parts marked with code 17328","Four applicability categories are clear and distinct, not overlapping conditions","Simple compliance deadlines (50 hours or prior to installation)","No defined terms section, no cross-references to other legislation beyond a manufacturer service bulletin","Background section explains rationale in plain language","Total length is approximately one page"],"plain_english_summary":"This CASA Airworthiness Directive mandates removal of piston pins P/N LW-14077 marked \"17328\" (manufactured Dec 1995–Sep 1996) from certain Textron Lycoming piston engines because they don’t meet specs and could cause engine failure. It applies to owners, operators, sellers and installers of affected engines or cylinder kits, and to anyone who’s installed those pins since Dec 1995.\n\nEngines in service must be fixed within 50 flight hours after 2 Jan 1997; new parts/kits must be checked before installation. Pins can be identified per Lycoming Service Bulletin 527B without full engine disassembly."}},"importantCases":[],"_links":{"self":"/api/acts/ad-lyc-100-piston-pin-p-n-lw-14077","history":"/api/acts/ad-lyc-100-piston-pin-p-n-lw-14077/history","analysis":"/api/acts/ad-lyc-100-piston-pin-p-n-lw-14077/analysis","conflicts":"/api/acts/ad-lyc-100-piston-pin-p-n-lw-14077/conflicts","importantCases":"/api/acts/ad-lyc-100-piston-pin-p-n-lw-14077/important-cases","documents":"/api/acts/ad-lyc-100-piston-pin-p-n-lw-14077/documents"}}