{"id":"F2006B11241","name":"AD/M20/37 - Lower Empennage Hinge Assembly - Inspection and Modification","slug":"ad-m20-37-lower-empennage-hinge-assembly-inspection-and-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":56961,"registerId":"commonwealth-F2006B11241-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/M20/37 - Lower Empennage Hinge Assembly - Inspection and Modification","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)  Mooney M20 Series Aeroplanes\n\n \n\n# AD/M20/37 Lower Empennage Hinge Assembly - Inspection\n\nand Modification\n\nApplicability: All model M20K with S/Nos. 25-0001 to 25-0086 and 25-0091 to 25-0094. Document:               Mooney SB No. M20-216.\n\nCompliance: Within 100 hours time in service after 31 July 1979.\n\n# 5/79\n\n \n\nBackground:  There is a possibility that some aeroplanes may not be able to achieve full 7` nose-up trim due to tolerance build up during manufacture of the 480009 hinge assembly.\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\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":1135},"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This airworthiness directive maintains its original targeted scope, addressing only a specific manufacturing tolerance issue affecting the trim system of particular Mooney M20K aircraft. It has not expanded beyond its initial flight safety purpose."},"complexity_factors":["Very short single-issue directive with no subsections","Narrow applicability limited to specific aircraft model and serial number ranges","Single compliance condition (100 hours time-in-service after fixed date)","Minimal cross-referencing (only to manufacturer Service Bulletin M20-216)","No defined terms section or nested conditional logic"],"plain_english_summary":"**What this does:** This is a safety order requiring owners of specific Mooney M20K aircraft to inspect and fix a hinge in the tail section (the \"lower empennage hinge assembly\").\n\n**Who it affects:** Owners of Mooney M20K planes with serial numbers 25-0001 to 25-0086 and 25-0091 to 25-0094.\n\n**What the problem is:** Manufacturing tolerances in hinge assembly part number 480009 might prevent the aircraft from achieving full nose-up trim (7 degrees). This could limit the pilot's ability to control the aircraft's pitch during flight.\n\n**What must be done:** Inspect and modify the hinge assembly according to Mooney Service Bulletin M20-216 within 100 hours of flying time after 31 July 1979."}},"importantCases":[],"_links":{"self":"/api/acts/ad-m20-37-lower-empennage-hinge-assembly-inspection-and-modification","history":"/api/acts/ad-m20-37-lower-empennage-hinge-assembly-inspection-and-modification/history","analysis":"/api/acts/ad-m20-37-lower-empennage-hinge-assembly-inspection-and-modification/analysis","conflicts":"/api/acts/ad-m20-37-lower-empennage-hinge-assembly-inspection-and-modification/conflicts","importantCases":"/api/acts/ad-m20-37-lower-empennage-hinge-assembly-inspection-and-modification/important-cases","documents":"/api/acts/ad-m20-37-lower-empennage-hinge-assembly-inspection-and-modification/documents"}}