{"id":"F2006B06285","name":"AD/PMC/29 - Propeller Hub - Replacement","slug":"ad-pmc-29-propeller-hub-replacement","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":47348,"registerId":"commonwealth-F2006B06285-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/PMC/29 - Propeller Hub - 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 - 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/29 Propeller Hub - Replacement 11/75\n\nApplicability: All propellers model B2D34C53-N/74E ( ) with S/Nos. 705516 to 705560 which are installed on any aircraft fitted with Lycoming 0-360 or IO-360 series engines.\n\n \n\nDocument: McCauley SB No. 115.\n\n \n\nCompliance: Before exceeding 1000 hours time in service. For hubs that have completed 975 hours or more total time in service as at 11 November 1975 - within 25 hours time in service after 11 November 1975.\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\n \n\n \n","sortOrder":0}],"analysis":{"kimi_summary":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":1953},"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This directive remains focused on its original 1975 purpose: addressing a specific manufacturing defect in a discrete batch of propeller hubs. It has not expanded beyond this targeted safety intervention."},"complexity_factors":["Single, unambiguous compliance action (replacement)","Narrow applicability limited to specific serial number range and engine type","Clear time-based compliance trigger using flight hours","Minimal cross-referencing (only to manufacturer Service Bulletin No. 115)"],"plain_english_summary":"**What this requires:** Aircraft owners must replace specific McCauley propeller hubs due to safety defects.\n\n**Who is affected:** Operators of aircraft with:\n- McCauley variable-pitch propellers model **B2D34C53-N/74E**\n- Serial numbers **705516 to 705560**\n- Installed on **Lycoming O-360 or IO-360 engines**\n\n**What you must do:**\n- Replace the propeller hub **before 1,000 hours of flight time** (time in service)\n- If the propeller already had **975+ hours** as of 11 November 1975: replace within **25 flight hours** after that date\n\n**Why this matters:** This prevents potential propeller hub failure, which could cause loss of propeller control or blade separation during flight. The technical specifications are detailed in McCauley Service Bulletin No. 115."}},"importantCases":[],"_links":{"self":"/api/acts/ad-pmc-29-propeller-hub-replacement","history":"/api/acts/ad-pmc-29-propeller-hub-replacement/history","analysis":"/api/acts/ad-pmc-29-propeller-hub-replacement/analysis","conflicts":"/api/acts/ad-pmc-29-propeller-hub-replacement/conflicts","importantCases":"/api/acts/ad-pmc-29-propeller-hub-replacement/important-cases","documents":"/api/acts/ad-pmc-29-propeller-hub-replacement/documents"}}