{"id":"F2006B06283","name":"AD/PMC/27 Amdt 1 - Attachment Studs","slug":"ad-pmc-27-amdt-1-attachment-studs","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":47341,"registerId":"commonwealth-F2006B06283-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/PMC/27 Amdt 1 - Attachment Studs","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 - 107 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n \n\n![](image.001.png)  Propellers - Variable Pitch - McCauley\n\n \n\nAD/PMC/27\n\nAmdt 1\n\n\nAttachment Studs 10/89\n\n \n\nApplicability: All model 3AF34C74, 3AF34C86 and 3AF34C92 propellers fitted to Cessna 411, 411A, 421, 421A, 421B or Beagle B-206 series 2 aircraft.\n\n \n\nRequirement: Action in accordance with McCauley SB No 102 and 102-1. Compliance:  Unless previously carried out - Prior to installation.\n\nNote: Modified hubs have 8 studs protruding 44.5mm to 45mm above the hub, 8 x 12mm thick spacers and the letter “P” added as a suffix to the part number.\n\n \n\nBackground:  This Amendment defines aircraft applicability to ensure all applicable hubs are properly modified.\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":2385},"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":true,"description":"The amendment refines the directive's scope by explicitly defining and listing the specific aircraft applicability (Cessna 411/421 series and Beagle B-206 Series 2) to ensure all affected propeller hubs are captured and properly modified, whereas the original directive lacked this specific aircraft-level targeting."},"complexity_factors":["Requires cross-referencing external technical documents (McCauley Service Bulletins 102 and 102-1) not reproduced in the directive","Precise mechanical specifications requiring measurement (stud protrusion 44.5mm-45mm, spacer thickness 12mm)","Technical aviation nomenclature for propeller models and aircraft airframe series"],"plain_english_summary":"This **Airworthiness Directive** (a mandatory safety order from the aviation regulator) requires a specific mechanical fix for certain aircraft propellers.\n\n**Who is affected:**\nOwners and operators of:\n* Cessna 411, 411A, 421, 421A, and 421B aircraft\n* Beagle B-206 Series 2 aircraft\n\n...that are fitted with McCauley propeller models 3AF34C74, 3AF34C86, or 3AF34C92.\n\n**What must be done:**\nBefore installing these propellers, the hub attachment studs must be modified according to manufacturer service bulletins (McCauley SB No. 102 and 102-1). A properly modified hub will have:\n* 8 studs sticking out 44.5mm to 45mm above the hub surface\n* 8 spacers that are 12mm thick\n* A part number ending in the letter **\"P\"**\n\n**Why this matters:**\nThis update clarifies exactly which aircraft types are covered to ensure all affected propeller hubs get the safety modification, preventing potential mechanical failure."}},"importantCases":[],"_links":{"self":"/api/acts/ad-pmc-27-amdt-1-attachment-studs","history":"/api/acts/ad-pmc-27-amdt-1-attachment-studs/history","analysis":"/api/acts/ad-pmc-27-amdt-1-attachment-studs/analysis","conflicts":"/api/acts/ad-pmc-27-amdt-1-attachment-studs/conflicts","importantCases":"/api/acts/ad-pmc-27-amdt-1-attachment-studs/important-cases","documents":"/api/acts/ad-pmc-27-amdt-1-attachment-studs/documents"}}