{"id":"F2006B06227","name":"AD/PHZL/70 - Hard Alloy Blades - Removal","slug":"ad-phzl-70-hard-alloy-blades-removal","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":47151,"registerId":"commonwealth-F2006B06227-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"AIRWORTHINESS DIRECTIVE","sectionType":"part","heading":"AIRWORTHINESS DIRECTIVE","content":"# AIRWORTHINESS DIRECTIVE\n\n![](image.001.png)\n\n![](image.001.png)  \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\nPropellers \\- Variable Pitch \\- Hartzell","sortOrder":0},{"sectionNumber":"AD/PHZL/70 Hard Alloy Blades - Removal 4","sectionType":"part","heading":"AD/PHZL/70 Hard Alloy Blades - Removal 4/2003","content":"# AD/PHZL/70 Hard Alloy Blades \\- Removal 4/2003\n\nApplicability: Hartzell Propeller Inc. model HC-B3TN-5( ) propellers, with part numbers (P/N’s) T10176H(B)-5, T10176H(K)-5, T10176H-5, T10178H-11, T10178H-11R,\n\nT10178H(B)-11, and T10178H(B)-11R blades that are installed on Mitsubishi Heavy Industries, Ltd MU-2 series aeroplanes.\n\nRequirement: Remove and replace propeller blades in accordance with paragraphs 3.A. through 3.C.(3) of the accomplishment instructions of Hartzell Propeller Inc. Service Bulletin HC-SB-61-250, Revision 1.\n\nNote: FAA AD 2003-04-23 Amendment 39-13072 refers.\n\nCompliance: Within 200 flight hours or 12 months from the effective date of this directive, whichever occurs first.\n\nThis Airworthiness Directive becomes effective on 17 April 2003.\n\nBackground: Certain hard alloy blades installed on Mitsubishi MU-2 aircraft have a history of blade failure. Replacement of the blades listed in this directive will reduce the likelihood of blade failure by replacement with a blade with greater resistance to intergranular corrosion. Failure of the blade can lead to severe damage to the aeroplane and subsequent loss of control of the aeroplane.\n\n![Signature of James Coyne, Delegate of the Civil Aviation Safety Authority.](image.002.png)  \n\nJames Coyne\n\nDelegate of the Civil Aviation Safety Authority 5 March 2003\n\n![](image.001.png)  \n\nThe above AD is notified in the Commonwealth of Australia Gazette on 26 March 2003.","sortOrder":1}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The directive does not expand regulatory scope beyond mandating replacement of the specified Hartzell blade P/Ns on Mitsubishi MU-2 aircraft. It is a targeted product-removal requirement tied to particular part numbers and a single aircraft type and does not amend broader regulatory definitions or applicability (see Applicability and Requirement)."},"complexity_factors":["Narrow, part-number-specific applicability: lists several Hartzell blade P/Ns installed on MU-2 aircraft (Applicability).","Mandated compliance with an external document: requires actions 'in accordance with paragraphs 3.A. through 3.C.(3)' of Hartzell SB HC-SB-61-250 Rev 1, obliging operators to obtain and follow that service bulletin (Requirement).","Fixed compliance window: 'within 200 flight hours or 12 months' creates a scheduling constraint that can affect maintenance planning and aircraft downtime (Compliance).","Safety-critical nature: Background states a history of blade failure and the risk of severe damage and loss of control, which raises urgency and inspection/repair quality requirements (Background).","Cross-reference to foreign regulator material: Note refers to FAA AD 2003-04-23, requiring operators to reconcile both directives where applicable (Requirement/Note).","Operator cost and logistics: removal and replacement imply parts procurement, certified maintenance labour, and record-keeping burdens borne by owners/operators (Requirement/Applicability).","Regulatory basis and delegate authority: issued under subregulation 39.1(1) of CAR 1998 by a CASA delegate, indicating administrative discretion in issuing the AD (opening paragraph/signature)."],"plain_english_summary":"This Airworthiness Directive requires owners/operators of Mitsubishi MU-2 aeroplanes fitted with specified Hartzell HC‑B3TN‑5( ) hard‑alloy propeller blades to remove and replace those blades in accordance with Hartzell Service Bulletin HC‑SB‑61‑250 Revision 1, within 200 flight hours or 12 months. CASA states the replacement is to reduce blade failures from intergranular corrosion that can cause severe aircraft damage and loss of control."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard airworthiness directive with tightly scoped applicability. It addresses a specific safety defect in specific aircraft components and mandates a specific remedy. The scope matches the original intent: remedying an unsafe condition in identified propeller blades."},"complexity_factors":["Single, specific technical requirement (blade replacement per manufacturer bulletin)","Clear applicability section with enumerated part numbers","Simple compliance deadline (200 hours OR 12 months)","No nested exceptions or conditional logic","No cross-references to other legislation beyond the cited FAA AD and manufacturer service bulletin","Short document (approximately 300 words)","Only one defined term of note ('P/N' = part number, self-explanatory from context)"],"plain_english_summary":"This CASA safety order requires owners/operators of Mitsubishi MU-2 aeroplanes fitted with specified Hartzell propeller blade part numbers to remove and replace those blades per Hartzell Service Bulletin HC‑SB‑61‑250 Rev 1, within 200 flight hours or 12 months of 17 April 2003. It responds to intergranular corrosion that has caused blade cracking and in‑flight failures that can destroy the aircraft and jeopardize pilot control."},"flash_summary_failed":{"failed":true,"reason":"Unauthenticated. Configure AI_GATEWAY_API_KEY or use a provider module. Learn more: https://ai-sdk.dev/unauthenticated-ai-gateway","source":"analysis-cron"}},"importantCases":[],"_links":{"self":"/api/acts/ad-phzl-70-hard-alloy-blades-removal","history":"/api/acts/ad-phzl-70-hard-alloy-blades-removal/history","analysis":"/api/acts/ad-phzl-70-hard-alloy-blades-removal/analysis","conflicts":"/api/acts/ad-phzl-70-hard-alloy-blades-removal/conflicts","importantCases":"/api/acts/ad-phzl-70-hard-alloy-blades-removal/important-cases","documents":"/api/acts/ad-phzl-70-hard-alloy-blades-removal/documents"}}