{"id":"F2006B06232","name":"AD/PHZL/75 - Propeller Hub Replacement","slug":"ad-phzl-75-propeller-hub-replacement","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":47167,"registerId":"commonwealth-F2006B06232-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"AIRWORTHINESS DIRECTIVE","sectionType":"part","heading":"AIRWORTHINESS DIRECTIVE","content":"# ![](image.001.png)  \nAIRWORTHINESS DIRECTIVE\n\nFor the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.1 (1) of CAR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.\n\n![](image.001.png)\n\nPropellers \\- Variable Pitch \\- Hartzell","sortOrder":0},{"sectionNumber":"AD/PHZL/75 Propeller Hub Replacement 3/2","sectionType":"part","heading":"AD/PHZL/75 Propeller Hub Replacement 3/2003","content":"# AD/PHZL/75 Propeller Hub Replacement 3/2003\n\nApplicability: Hartzell 2 Bladed “Y” shank propellers fitted with aluminium hub part numbers D- 6522-1, D-6522-2, D-6529-1, and D-6559-3 with a hub serial number that is listed in Table 1 of this Directive.\n\nRequirement: Remove from service applicable Hartzell aluminium hubs in accordance with Hartzell ASB HC-ASB-61-259.\n\nNote 1: FAA AD 2003-01-03 Amdt 39-13014 refers.\n\nNote 2: Hubs listed in Table 1 of this Directive are not to be installed.\n\nCompliance: 1. Within 50 hours propeller hub time since new or 12 months from the effective date of this Directive, whichever occurs first, for propeller hubs installed on:\n\n    Piper PA-32 series aircraft with Textron Lycoming 540 series engines that are rated at 300HP or higher; or\n\n    b. Pilatus Britten Norman or Britten Norman BN-2 series aircraft (also known as Islander or Trislander) with Textron Lycoming 540 series engines; or\n\n    c. Any aircraft certified in the acrobatic category; or\n\n    d. Any aircraft routinely exposed to acrobatic manoeuvres; or\n\n    e. Any aircraft that has been used for agricultural operations whilst the applicable propeller was installed.\n\n2. For propeller hubs installed on aircraft apart from those listed in Paragraph 1, within 100 hours propeller hub time since new or twelve months from the effective date of this Directive, whichever occurs first.","sortOrder":1},{"sectionNumber":"Propellers - Variable Pitch - Hartzell","sectionType":"part","heading":"Propellers - Variable Pitch - Hartzell","content":"## Propellers \\- Variable Pitch \\- Hartzell\n\nAD/PHZL/75 (Continued)","sortOrder":2},{"sectionNumber":"Table 1. Applicable Propellers and Hubs","sectionType":"part","heading":"Table 1. Applicable Propellers and Hubs","content":"## Table 1. Applicable Propellers and Hubs\n\n| Propeller S/N | Hub S/N | Hub P/N  |\n| ------------- | ------- | -------- |\n| AU11115B      | A61365B | D-6522-1 |\n| AU11116B      | A61366B | D-6522-1 |\n| AU11117B      | A61367B | D-6522-1 |\n| AU11119B      | A61369B | D-6522-1 |\n| AU11125B      | A61375B | D-6522-1 |\n| AU11131B      | A61381B | D-6522-1 |\n| AU11134B      | A61384B | D-6522-1 |\n| AU11135B      | A61385B | D-6522-1 |\n| AY515B        | A61397B | D-6522-2 |\n| AY516B        | A61398B | D-6522-2 |\n| CH36140B      | A61409B | D-6529-1 |\n| CH36141B      | A61410B | D-6529-1 |\n| CH36151B      | A61420B | D-6529-1 |\n| CH36152B      | A61421B | D-6529-1 |\n| CH36153B      | A61422B | D-6529-1 |\n| CH36157B      | A61427B | D-6529-1 |\n| EU376B        | A61443B | D-6559-3 |\n| CH36172B      | A61547B | D-6529-1 |\n| CH36159B      | A61553B | D-6529-1 |\n| CH36160B      | A61554B | D-6529-1 |\n| CH36162B      | A61556B | D-6529-1 |\n| CH36163B      | A61557B | D-6529-1 |","sortOrder":3}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This Airworthiness Directive maintains its original narrow scope — addressing a specific manufacturing defect in specific Hartzell propeller hubs. The tiered compliance structure (different deadlines for different aircraft types) is a standard risk-based regulatory approach for aviation safety, not scope creep. The directive remains tightly focused on the identified unsafe condition."},"complexity_factors":["Multiple overlapping applicability criteria (part numbers AND serial numbers from Table 1)","Tiered compliance deadlines based on five different aircraft/engine/usage categories","Cross-reference to external technical document (Hartzell ASB HC-ASB-61-259) for actual removal procedures","Reference to corresponding FAA Airworthiness Directive (2003-01-03) for context","Conditional logic: 'whichever occurs first' calculations for compliance timing"],"plain_english_summary":"This CASA safety order requires owners/operators to remove and replace specific Hartzell aluminium propeller hubs (listed serial numbers) due to supplier-forging defects that can crack and cause in‑flight propeller separation. Removal must follow Hartzell ASB HC‑ASB‑61‑259.\n\nDeadlines vary by use—sooner for high‑stress operations (e.g., high‑power, acrobatic, agricultural)—and the listed hubs are permanently prohibited from installation."},"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":4,"scope_assessment":{"changed":false,"description":"The Directive's scope aligns with its stated safety objective to remove defective hubs: it targets specific Hartzell aluminium hub P/Ns and S/Ns and sets shorter compliance windows for higher‑risk aircraft or uses (Requirement; Table 1; Compliance). Decision authority lies with the CASA delegate who issued the AD; compliance costs and replacement obligations fall to aircraft owners/operators who must follow Hartzell ASB HC‑ASB‑61‑259. No indication in the source text that the scope was broadened beyond that safety aim."},"complexity_factors":["Differentiated compliance windows: 50 hours propeller hub time or 12 months for higher‑risk uses vs 100 hours or 12 months otherwise (Compliance paragraphs 1–2).","Narrow applicability tied to specific hub part numbers and a long list of serial numbers, requiring operators to check Table 1 for affected units (Table 1).","Multiple aircraft categories trigger earlier action (specific models, acrobatic category, routine exposure to aerobatics, agricultural use) which complicates risk classification (Applicability; Compliance paragraph 1 a–e).","Mandatory removal and prohibition on reinstalling listed hubs, and instruction to comply with Hartzell ASB HC‑ASB‑61‑259 for replacement procedures (Requirement; Note 2).","Cross‑reference to FAA AD 2003‑01‑03 and reliance on manufacturer advisories for the unsafe‑condition rationale (Notes; Background).","Operational/admin burden of tracking hub time since new and correlating that with the effective date to determine compliance deadlines (Compliance)."],"plain_english_summary":"This Directive requires removal and bans reinstallation of specified Hartzell aluminium propeller hubs (listed by part and serial number). Owners/operators must replace affected hubs following the Hartzell service bulletin.\n\nIt applies to aircraft fitted with those propellers — notably certain PA‑32 and Britten Norman/Islander types, aircraft used for aerobatics or agricultural work — because the manufacturer reported forging defects that could lead to hub cracks and propeller failure."}},"importantCases":[],"_links":{"self":"/api/acts/ad-phzl-75-propeller-hub-replacement","history":"/api/acts/ad-phzl-75-propeller-hub-replacement/history","analysis":"/api/acts/ad-phzl-75-propeller-hub-replacement/analysis","conflicts":"/api/acts/ad-phzl-75-propeller-hub-replacement/conflicts","importantCases":"/api/acts/ad-phzl-75-propeller-hub-replacement/important-cases","documents":"/api/acts/ad-phzl-75-propeller-hub-replacement/documents"}}