{"id":"F2006B06277","name":"AD/PMC/14 Amdt 10 - Threaded Propeller Hubs","slug":"ad-pmc-14-amdt-10-threaded-propeller-hubs","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":47322,"registerId":"commonwealth-F2006B06277-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/PMC/14 Amdt 10 - Threaded Propeller Hubs","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 107 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nPropellers \\- Variable Pitch \\- McCauley\n\nAD/PMC/14\n\nAmdt 10\n\n  \nThreaded Propeller Hubs 4/95\n\nApplicability: All McCauley threaded propeller hubs.\n\nNote: To identify a threaded hub, inspect hub P/N. If numerals after the “C” are less than 200 the hub is of the threaded type. e.g. 2AF34C17. If numerals after the “C” are 200 or higher hub is non threaded hub and the requirements of this Directive do not apply. e.g. B2A34C205.\n\nRequirement: 1. Remove spinner and check whether hub is a dye oil filled or non dye oil filled type.\n\n    2. If hub is a dye oil filled type visually check hub for signs of dye oil leaks. If the spinner backing plate prevents a thorough hub inspection, removal of the propeller and backing plate will be required. If the inspection confirms there is no leakage from the hub and the correct quantity of dye oil is contained in the hub no further action is required and this Directive may be certified as complied with. If any dye oil leakage is apparent, the propeller is to be removed from service for dismantling and internal hub inspection procedures.\n\nNote: To check for correct oil level, place two bladed propeller vertical. In a three bladed propeller the number one blade should be vertical. Remove oil filler plug, which should be approximately at the ten o’clock position and confirm dye oil level is to bottom of oil filler hole.\n\n    3. If hub is a non oil filled type or is not currently dye oil filled, remove propeller from engine and remove backing plate, if fitted. Using Group 1 dye penetrant to CAO 108.10 inspect hub in the following areas:\n\nNote: Ensure solvent does not enter blade socket area as loss of lubricant from this area can affect blade pitch change action.\n\n    (a) the outer 38 mm (one and one half inches) of the complete circumference of each blade socket paying particular attention to the rear segment of each socket;\n\n    (b) the rear circumference of the hub barrel adjacent to the attachment face, including the complete mounting flange face; and\n\n    (c) inspect blades for excessive looseness and ensure both expansion lock plugs are installed in each blade retention nut.\n\n    4. After completion of dye penetrant inspection lubricate the area where the steel shim/circlip are mounted in the blade retaining ferrule using Aeroshell W65. If Aeroshell W65 is unavailable any SAE 10W or SAE 10W multi-grade piston engine oil is acceptable.\n\nCOMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 107 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\nCompliance: For propellers installed on aircraft certificated in the Agricultural or Acrobatic Category and which are known to have exceeded 400 hours total time in service - Unless previously carried out, within 100 hours time in service (TIS) from 30 March 1995. Thereafter, reinspect at intervals not exceeding 125 hours TIS.\n\nFor propellers installed on an aircraft certificated in other than Agricultural or Acrobatic Category and which are known to have exceeded 700 hours total time in service \\- Unless previously carried out, within 100 hours time in service (TIS) from 30 March 1995. Thereafter, reinspect at intervals not exceeding 125 hours TIS.\n\nBackground: Recently there have been several cases where failure to detect a cracked hub has resulted in the loss of a propeller blade. This Directive was previously amended to require non dye oil filled propellers to be removed and inspected using red dye penetrant, and a warning to operators of potential pitch change problems if solvent is allowed to enter the blade socket area. This amendment is raised in sequence to require inspection for blade looseness, presence of expansion lock plugs and lubrication of the steel shim/circlip mounted in the blade retention nut.","sortOrder":0}],"analysis":{"flash_summary_failed":{"failed":true,"reason":"A positive credit balance is required for all requests, including BYOK, so fallback providers remain available. Add credits at https://vercel.com/d?to=%2F%5Bteam%5D%2F%7E%2Fai%3Fmodal%3Dtop-up to continue.","source":"analysis-cron"},"flash_summary":{"complexity_score":5,"scope_assessment":{"changed":true,"description":"This amendment extends prior requirements by adding inspection for blade looseness, verification of expansion lock plugs in each blade retention nut, and mandatory lubrication of the steel shim/circlip in the blade retention ferrule; it preserves the prior dye‑penetrant inspection mandate and solvent‑avoidance warning."},"complexity_factors":["Technical identification rule based on part number (numerals after “C” < 200) — requires accurate P/N checks.","Conditional inspection paths: dye‑oil filled vs non dye‑oil filled hubs (different steps and possible removal).","Physical removal may be required (spinner/backing plate or full propeller removal) to achieve inspection access.","Detailed dye penetrant inspection areas and cautions (outer 38 mm of blade sockets, rear hub barrel, mounting flange, blade retention hardware).","New checks added: blade looseness, presence of expansion lock plugs, and lubrication of steel shim/circlip (specific lubricant allowed).","Specified acceptable lubricants (Aeroshell W65 or SAE 10W alternatives) — narrow material choice affects logistics.","Multiple compliance thresholds and intervals: differing initial windows depending on aircraft category and total time in service (400/700 hours) and mandatory 125‑hour reinspection interval.","Safety‑critical outcome (loss of blade if cracked hub undetected) raises urgency and may increase frequency/cost of inspections.","Operator responsibility to bear labour/material costs and make go/no‑go maintenance decisions; potential grounding while propeller removed."],"plain_english_summary":"Mandates inspections of all McCauley threaded propeller hubs to detect dye‑oil leaks, cracked hubs, blade looseness, missing expansion lock plugs, and to require lubrication of the steel shim/circlip in the blade retention ferrule. Threaded hubs are identified by part‑number numerals after the “C” being less than 200. (Requirement: inspection steps 1–4.)\n\nThis affects aircraft owners/operators with affected hubs, who must inspect (and, where required, remove) propellers within specified service‑hour windows and at 125‑hour reinspection intervals; operators bear the inspection, removal and maintenance costs. (Compliance.)"},"kimi_summary":{"content_quality":"ok","complexity_score":4,"scope_assessment":{"changed":true,"description":"This is Amendment 10 to the original directive. The Background section explicitly states this amendment expanded the original scope: it added requirements to check for blade looseness, verify expansion lock plugs are present, and lubricate the steel shim/circlip area. The original directive only required dye penetrant inspection for non-oil-filled propellers. The directive has evolved from a simple crack-detection mandate to a more comprehensive hub maintenance protocol."},"complexity_factors":["Multiple conditional pathways based on hub type (dye oil filled vs non-oil filled)","Different compliance schedules based on aircraft category (Agricultural/Acrobatic vs other categories) and total flight hours","Specific technical measurements (38mm inspection zone, 10 o'clock oil filler position)","Cross-reference to CAO 108.10 (Civil Aviation Order) for dye penetrant standards","Specific part number identification logic (numerals after 'C' < 200)","Nested procedural requirements with multiple sub-steps and cautionary notes"],"plain_english_summary":"This AD mandates regular inspections of certain McCauley threaded propeller hubs to detect cracks that can lead to blade separation. Depending on hub type, inspections use oil-leak checks or red dye penetrant after propeller removal, with specific servicing and safety precautions.\n\nIt affects owners/operators of aircraft with the listed McCauley hubs—especially high‑use agricultural and aerobatic props—and requires initial and recurring inspections to prevent catastrophic failures."}},"importantCases":[],"_links":{"self":"/api/acts/ad-pmc-14-amdt-10-threaded-propeller-hubs","history":"/api/acts/ad-pmc-14-amdt-10-threaded-propeller-hubs/history","analysis":"/api/acts/ad-pmc-14-amdt-10-threaded-propeller-hubs/analysis","conflicts":"/api/acts/ad-pmc-14-amdt-10-threaded-propeller-hubs/conflicts","importantCases":"/api/acts/ad-pmc-14-amdt-10-threaded-propeller-hubs/important-cases","documents":"/api/acts/ad-pmc-14-amdt-10-threaded-propeller-hubs/documents"}}