{"id":"F2006B10996","name":"AD/JT8D/6 - Replacement or Inspection of LP Turbine Shaft and No. 2 Hub","slug":"ad-jt8d-6-replacement-or-inspection-of-lp-turbine-shaft-and-no-2-hub","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":56587,"registerId":"commonwealth-F2006B10996-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/JT8D/6 - Replacement or Inspection of LP Turbine Shaft and No. 2 Hub","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 - 106 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n \n\n![](image.001.png)  Pratt and Whitney Turbine Engines - JT8D Series\n\n \n\nAD/JT8D/6 Replacement or Inspection of LP Turbine Shaft and No. 2 Hub\n\nApplicability: JT8D-1, -1A, -7, -7A engines.\n\n \n\nDocument: 1. Pratt & Whitney Alert SB No. 4357, Rev. 3; or\n\n \n\n2. FAA AD 75-01-01 amendment 39-2358; or 3. AD/PW-T/33.\n\nCompliance: As detailed in the Requirement Document.\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\n \n\n\n1/75\n","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The AD text sets a specific, limited scope: replacement or inspection of the LP turbine shaft and No. 2 hub on JT8D-1, -1A, -7 and -7A engines (Applicability). The document does not indicate any expansion or contraction of that scope within its text; it instead refers to external Requirement Documents for procedural detail (Document, Compliance). There is no statement in this text that the AD changes prior scope beyond the parts and engine models listed."},"complexity_factors":["Short, narrowly targeted directive text with limited internal technical detail (only names the affected parts and engine models).","Primary substantive requirements are delegated to external documents (Pratt & Whitney Alert SB No. 4357 Rev. 3; FAA AD 75-01-01; AD/PW-T/33), requiring users to obtain and interpret those documents.","No timelines, inspection intervals or technical procedures stated in the AD text itself, increasing practical complexity for implementers who must consult the Requirement Document.","Clear, narrow applicability (specific JT8D variants) reduces scope complexity but requires correct engine identification by operators.","No enforcement, exemption or compliance-timing language included in the text, which may create implementation uncertainty without the Requirement Document."],"plain_english_summary":"This airworthiness directive mandates replacement or inspection of the low‑pressure turbine shaft and No. 2 hub on Pratt & Whitney JT8D‑1, ‑1A, ‑7 and ‑7A engines, but delegates the step‑by‑step requirements to referenced “Requirement Documents” (Pratt & Whitney Alert SB No. 4357 Rev. 3; FAA AD 75‑01‑01; AD/PW‑T/33).\n\nIt affects operators, owners and maintenance organisations for those engines and matters because compliance is mandatory, carrying maintenance, cost and downtime implications determined by the referenced documents."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted safety directive focused on specific engine components. It has not expanded beyond its original purpose of addressing a known airworthiness issue with LP turbine shafts and No. 2 hubs in JT8D engines."},"complexity_factors":["Very short document (approximately 200 words)","Only 3 defined applicability criteria (specific engine models)","No nested conditional logic or exceptions","Single compliance pathway with three alternative reference documents","No interpretation section or defined terms","Straightforward mandate: inspect or replace specific parts"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** issued by Australia's Civil Aviation Safety Authority (CASA). It mandates specific maintenance actions for certain Pratt & Whitney jet engines used in aircraft.\n\n**What it does:**\n- Requires airlines and aircraft operators to either **replace or inspect** two specific engine components: the **Low Pressure (LP) Turbine Shaft** and the **No. 2 Hub**\n- These components are critical parts of the engine's turbine section\n\n**Who it affects:**\n- Operators of aircraft using **JT8D-1, -1A, -7, or -7A model engines** (these are older Pratt & Whitney turbofan engines commonly used on Boeing 727 and early 737 aircraft, as well as McDonnell Douglas DC-9s)\n- Maintenance organisations servicing these engines\n\n**Why it matters:**\n- **Safety critical:** These directives are issued when there's a known risk of engine failure that could endanger the aircraft\n- **Legally binding:** Compliance is mandatory under Australian civil aviation law\n- Operators must follow the detailed instructions in the referenced Pratt & Whitney service bulletin or the equivalent FAA directive\n\n**How to comply:**\nOperators must follow the technical requirements set out in:\n- Pratt & Whitney Alert Service Bulletin No. 4357 (Revision 3), **or**\n- FAA Airworthiness Directive 75-01-01, **or** \n- An earlier Australian directive AD/PW-T/33"}},"importantCases":[],"_links":{"self":"/api/acts/ad-jt8d-6-replacement-or-inspection-of-lp-turbine-shaft-and-no-2-hub","history":"/api/acts/ad-jt8d-6-replacement-or-inspection-of-lp-turbine-shaft-and-no-2-hub/history","analysis":"/api/acts/ad-jt8d-6-replacement-or-inspection-of-lp-turbine-shaft-and-no-2-hub/analysis","conflicts":"/api/acts/ad-jt8d-6-replacement-or-inspection-of-lp-turbine-shaft-and-no-2-hub/conflicts","importantCases":"/api/acts/ad-jt8d-6-replacement-or-inspection-of-lp-turbine-shaft-and-no-2-hub/important-cases","documents":"/api/acts/ad-jt8d-6-replacement-or-inspection-of-lp-turbine-shaft-and-no-2-hub/documents"}}