{"id":"F2006B06288","name":"AD/PMC/33 - Propeller Hubs - Modification to Oil Filled Standard","slug":"ad-pmc-33-propeller-hubs-modification-to-oil-filled-standard","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":47357,"registerId":"commonwealth-F2006B06288-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/PMC/33 - Propeller Hubs - Modification to Oil Filled Standard","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/33 Propeller Hubs - Modification to Oil Filled Standard\n\n\n4/78\n\n \n\nApplicability: All model D2AF34C61 propellers fitted to Cessna 336 and 337 series aircraft, which have not been modified to the oil Filled Standard.\n\n \n\nNote: Oil filled hubs have a letter suffix “O” in the hub model designation and are fitted with a filler plug.\n\n \n\nRequirement: Modify the propeller hub to the oil filled standard in accordance with McCauley SB No. 123, para. (3) of “Corrections”.\n\n \n\nCompliance: Before installation in an aircraft following next reconditioning completed after 31 May 1978.\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":1761},"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This airworthiness directive retains its original narrow, technical scope. Issued in 1978, it addresses a specific mechanical safety issue in identified propeller assemblies and has not expanded beyond its initial purpose of mandating a design standard."},"complexity_factors":["Single conditional compliance trigger (reconditioning after fixed date)","One external technical reference (McCauley Service Bulletin No. 123)","Narrow applicability limited to specific propeller model and aircraft series","Minimal text (under 150 words of operative provisions)"],"plain_english_summary":"**What this is:** A mandatory safety directive requiring a mechanical upgrade to specific aircraft propellers to improve their lubrication system.\n\n**Who it affects:** Owners and operators of **Cessna 336 and 337 series aircraft** fitted with **McCauley model D2AF34C61 propellers**—but only those that haven't already been converted to the \"oil filled\" design.\n\n**What it requires:** The propeller hub must be modified to meet the \"oil filled standard.\" This involves fitting a filler plug so the hub can hold oil for lubrication and cooling. You can identify compliant hubs by the letter **\"O\"** in the hub model designation. The modification must follow the manufacturer's Service Bulletin No. 123, specifically paragraph (3) of the \"Corrections\" section.\n\n**When:** Before reinstalling the propeller on an aircraft, following the next reconditioning service completed after 31 May 1978.\n\n**Why it matters:** Oil-filled hubs run cooler and are less likely to fail in flight than non-oil-filled versions."}},"importantCases":[],"_links":{"self":"/api/acts/ad-pmc-33-propeller-hubs-modification-to-oil-filled-standard","history":"/api/acts/ad-pmc-33-propeller-hubs-modification-to-oil-filled-standard/history","analysis":"/api/acts/ad-pmc-33-propeller-hubs-modification-to-oil-filled-standard/analysis","conflicts":"/api/acts/ad-pmc-33-propeller-hubs-modification-to-oil-filled-standard/conflicts","importantCases":"/api/acts/ad-pmc-33-propeller-hubs-modification-to-oil-filled-standard/important-cases","documents":"/api/acts/ad-pmc-33-propeller-hubs-modification-to-oil-filled-standard/documents"}}