{"id":"F2006B06223","name":"AD/PHZL/65 - Hub Pilot Tube Bore Inspection","slug":"ad-phzl-65-hub-pilot-tube-bore-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":47138,"registerId":"commonwealth-F2006B06223-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/PHZL/65 - Hub Pilot Tube Bore Inspection","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 \\- Hartzell\n\nAD/PHZL/65 Hub Pilot Tube Bore Inspection 5/94\n\nApplicability: All HC-B4 series propellers which may have been previously installed on MU-2 series aircraft and have not had the hub bores inspected in accordance with Hartzell Alert SB A182 or A183.\n\nNote 1: Subject propellers are installed on but not limited to Beech F90 King Air, A100 and A100A King Air, B100 King Air, CASA C-212-CB, CASA C-212-CC, CF,\n\nDeHaviland Heron \\- Saunders Conversion ST-27B, Dornier Do 228-100, \\-101, \\-200,\n\n\\-201, \\-202 and \\-212, Embraer EMB-121A1 Xingu, Fairchild SA226-TB Merlin IIIB, Let L-410A and Shorts SC-7 series 3, variant 200.\n\nNote 2: Hubs previously inspected in accordance with AD/PHZL/64 are exempt from the requirements of this Directive.\n\nRequirement: Action in accordance with Hartzell Alert SB A186 dated 25 January 1994.\n\nNote: FAA AD 94-03-11 amdt 39-8818 refers.\n\nCompliance: As specified in the requirement document.\n\nBackground: The propeller manufacturer has expressed concern that a large number of 4 bladed hubs originally supplied to Mitsubishi may have seen service on MU-2 series aircraft and due to the higher operating stresses when fitted to these aircraft the hub pilot tube bores require inspection for signs of fatigue cracking.","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":3,"scope_assessment":{"changed":false,"description":"The directive's scope is limited to HC‑B4 series hubs that possibly served on MU‑2 aircraft and excludes hubs already inspected under AD/PHZL/64. This matches the stated background concern about higher MU‑2 operating stresses and does not broaden obligations beyond requiring the specified inspection per the referenced service bulletin."},"complexity_factors":["Relies on external technical document (Hartzell Alert SB A186) for the detailed inspection procedure and compliance timing rather than specifying requirements in the directive itself.","Applicability phrasing — 'may have been previously installed' — creates an identification and record-keeping burden for operators and maintainers.","Exemption cross-reference to AD/PHZL/64 requires checking historical inspection status across directives.","List of multiple aircraft types increases the number of operators affected and complexity of fleet tracking.","Reference to FAA AD 94-03-11 introduces an additional external regulatory linkage to consider.","Enforcement and compliance administration rest with CASA, requiring coordination between operators and the regulator."],"plain_english_summary":"This directive requires inspection of the hub pilot tube bores on HC‑B4 series Hartzell four‑bladed propellers that may have previously been installed on Mitsubishi MU‑2 aircraft, to be done in accordance with Hartzell Alert Service Bulletin A186. Hubs already checked under AD/PHZL/64 are exempt. Operators and maintenance organisations pay for inspections and any repairs; the Civil Aviation Safety Authority enforces compliance. The inspection is intended to detect fatigue cracking caused by higher MU‑2 operating stresses and may lead to repair or replacement."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This Airworthiness Directive maintains its original narrow scope — a targeted safety inspection for a specific propeller model with a known operational history concern. The scope has not expanded beyond the original safety issue identified by the manufacturer."},"complexity_factors":["Single, specific mechanical inspection requirement","Only 2 defined applicability criteria (propeller series + installation history)","One clear exemption (previous inspection under AD/PHZL/64)","No nested conditional logic or cross-references to other legislation beyond a single referenced service bulletin","Short document (approximately 200 words)","Straightforward compliance mechanism (follow manufacturer's service bulletin)"],"plain_english_summary":"CASA has issued a safety directive requiring inspection of hub pilot tube bores on Hartzell HC‑B4 series propellers after the manufacturer found higher stresses (notably from MU‑2 use) can cause fatigue cracking. It affects operators and maintenance organisations using these propellers on various aircraft and aims to detect cracks before failure by following Hartzell Alert Service Bulletin A186.\n\nPropellers already inspected under AD/PHZL/64 are exempt; the directive aligns with FAA AD 94‑03‑11 for further guidance."}},"importantCases":[],"_links":{"self":"/api/acts/ad-phzl-65-hub-pilot-tube-bore-inspection","history":"/api/acts/ad-phzl-65-hub-pilot-tube-bore-inspection/history","analysis":"/api/acts/ad-phzl-65-hub-pilot-tube-bore-inspection/analysis","conflicts":"/api/acts/ad-phzl-65-hub-pilot-tube-bore-inspection/conflicts","importantCases":"/api/acts/ad-phzl-65-hub-pilot-tube-bore-inspection/important-cases","documents":"/api/acts/ad-phzl-65-hub-pilot-tube-bore-inspection/documents"}}