{"id":"F2006B11071","name":"AD/LA-4/20 - Main Landing Gear - Rocker Castings P/N 2-4113-1 - Inspection and Replacement","slug":"ad-la-4-20-main-landing-gear-rocker-castings-p-n-2-4113-1-inspection-and-replacement","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":56706,"registerId":"commonwealth-F2006B11071-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/LA-4/20 - Main Landing Gear - Rocker Castings P/N 2-4113-1 - Inspection and Replacement","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)  Consolidated Aeronautics, Colonial and LA-4 Series Aeroplanes\n\n \n\n# AD/LA-4/20 Main Landing Gear - Rocker Castings\n\nP/N 2-4113-1 - Inspection and Replacement\n\nApplicability: All model LA4-200 with S/Nos. 740 to 997.\n\n# 1/80\n\n \n\nRequirement: 1. Visually inspect Rocker Castings P/No. 2-4113-1, located at upper end of main landing gear struts, for cracks radiating from the bolt holes.\n\n \n\n2. Replace Rocker Castings P/No. 2-4113-1 with fabricated items P/Nos. 2-4113-3 or 2-4110-7.\n\n \n\nNote: SB No. B63-4497 refers.\n\n \n\nCompliance: 1. At each daily or overnight inspection. For aircraft maintained in accordance with ANO 100.5.1 this Directive shall be entered on the maintenance release as maintenance required. The inspection may be performed by the pilot in command, in which case certification is not required. In all other cases certification may be made on the maintenance release. This inspection may also be performed and certified by any Licensed Aircraft Maintenance Engineer.\n\n \n\n2. Before 1 January 1981.\n\n \n\nBackground: Failure of the subject P/No. Rocker Castings has occurred on overseas registered aeroplanes.\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":{"kimi_summary":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":1806},"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This airworthiness directive maintains its original narrow scope as a targeted safety intervention for a specific mechanical defect in defined aircraft models."},"complexity_factors":["Narrow applicability restricted to specific aircraft model and serial number range (740-997)","Multiple alternative replacement part numbers specified (2-4113-3 or 2-4110-7)","Cross-reference to external technical document (Service Bulletin B63-4497)","Conditional certification requirements depending on whether pilot or engineer performs inspection","Integration with Air Navigation Order 100.5.1 maintenance release documentation requirements"],"plain_english_summary":"This AD requires owners/operators of Lake/Colonial LA4-200 aircraft (S/N 740–997) to perform daily/overnight visual inspections of the main landing gear rocker castings (P/N 2-4113-1) for crack growth from the bolt holes, and to replace those castings with fabricated parts (P/N 2-4113-3 or 2-4110-7) by 1 January 1981.  \n\nIt responds to overseas failures of identical parts and aims to prevent landing-gear structural failure."}},"importantCases":[],"_links":{"self":"/api/acts/ad-la-4-20-main-landing-gear-rocker-castings-p-n-2-4113-1-inspection-and-replacement","history":"/api/acts/ad-la-4-20-main-landing-gear-rocker-castings-p-n-2-4113-1-inspection-and-replacement/history","analysis":"/api/acts/ad-la-4-20-main-landing-gear-rocker-castings-p-n-2-4113-1-inspection-and-replacement/analysis","conflicts":"/api/acts/ad-la-4-20-main-landing-gear-rocker-castings-p-n-2-4113-1-inspection-and-replacement/conflicts","importantCases":"/api/acts/ad-la-4-20-main-landing-gear-rocker-castings-p-n-2-4113-1-inspection-and-replacement/important-cases","documents":"/api/acts/ad-la-4-20-main-landing-gear-rocker-castings-p-n-2-4113-1-inspection-and-replacement/documents"}}