{"id":"F2006B11240","name":"AD/M20/36 - Rear Spar Centre Splice - Inspection","slug":"ad-m20-36-rear-spar-centre-splice-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":56960,"registerId":"commonwealth-F2006B11240-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/M20/36 - Rear Spar Centre Splice - Inspection","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nMooney M20 Series Aeroplanes\n\nAD/M20/36 Rear Spar Centre Splice \\- Inspection 5/79\n\nApplicability: All model M20B with S/Nos. 1701 to 1851, 1853 to 1953. All model M20C with S/Nos. 1852, 1940-3342, 3344-3445, 3447-3466, 670001-670123, 670125-670134,\n\n670136-670149 and 680001-680198. All model M20D with S/Nos. 101-260. All model M20E with S/Nos. 101-1219, 1221, 1223-1308, 670001-670062. All model\n\nM20F with S/Nos. 660002-660004, 670001-670363, 670365-670385, 670367- 670482,670484-670539, 680001-680206. All model M20G with S/Nos.680001 to\n\n680164.\n\nDocument: Mooney SB No. M20-217.\n\nCompliance: Within 10 hours time in service for those aeroplanes which have achieved 500 hours time in service and thereafter at intervals not exceeding 500 hours time in service until modified in accordance with SB No. M20-217.\n\nBackground: There is a possibility of failure of the rear spar centre splice due to cracking and associated crack growth in service.","sortOrder":0}],"analysis":{"kimi_summary":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":2006},"content_quality":"ok","complexity_score":4,"scope_assessment":{"changed":false,"description":"The directive maintains its original scope as a targeted safety inspection requirement for a specific structural defect in defined aircraft models. No expansion beyond the original airworthiness safety purpose is evident."},"complexity_factors":["Highly fragmented applicability matrix covering 6 model variants with 30+ non-contiguous serial number ranges requiring cross-referencing against aircraft logs","Technical aviation terminology ('time in service', 'rear spar centre splice') requiring specialist engineering knowledge to interpret","Dual-phase compliance structure with both immediate (10-hour) and recurring (500-hour) inspection intervals based on accumulated flight hours","Dependency on external technical document (Service Bulletin M20-217) for permanent modification requirements"],"plain_english_summary":"This Airworthiness Directive (a mandatory safety rule) requires owners of specific Mooney M20 aircraft to inspect a critical structural part called the **rear spar centre splice** — the joint where sections of the main wing spar connect.\n\n**Who is affected:**\nOwners of Mooney M20B, M20C, M20D, M20E, M20F, and M20G model aircraft with specific serial numbers listed in the directive (ranging from 1940s-1980s manufacture).\n\n**What must be done:**\n*   **First inspection:** Within 10 flight hours if the aircraft has flown 500 or more hours total\n*   **Ongoing inspections:** Every 500 flight hours thereafter\n*   **Stop condition:** Continue until the aircraft is modified according to Mooney Service Bulletin M20-217\n\n**Why this matters:**\nThe rear spar centre splice can develop cracks during normal flight operations. If undetected, these cracks could grow and cause the wing structure to fail, leading to loss of the aircraft."}},"importantCases":[],"_links":{"self":"/api/acts/ad-m20-36-rear-spar-centre-splice-inspection","history":"/api/acts/ad-m20-36-rear-spar-centre-splice-inspection/history","analysis":"/api/acts/ad-m20-36-rear-spar-centre-splice-inspection/analysis","conflicts":"/api/acts/ad-m20-36-rear-spar-centre-splice-inspection/conflicts","importantCases":"/api/acts/ad-m20-36-rear-spar-centre-splice-inspection/important-cases","documents":"/api/acts/ad-m20-36-rear-spar-centre-splice-inspection/documents"}}