{"id":"F2006B11003","name":"AD/JT9D/10 - Main Gearbox Assembly - Magnetic Plug Inspection","slug":"ad-jt9d-10-main-gearbox-assembly-magnetic-plug-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":56598,"registerId":"commonwealth-F2006B11003-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/JT9D/10 - Main Gearbox Assembly - Magnetic Plug Inspection","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 - JT9D Series\n\n \n\nAD/JT9D/10 Main Gearbox Assembly - Magnetic Plug Inspection 2/80\n\nApplicability: JT9D-3, -3A, -7, -7A, -7H, -7AH, 7A(SP), -7F, -7J.\n\n \n\nDocument: 1. Pratt & Whitney Aircraft Alert SB No. 4854, Rev. 1; or\n\n \n\n2.    FAA AD 78-08-13 : Amendment 39-3195 as amended by Amendment 39-3710; or\n\n \n\n3.    AD/PW-T/45A.\n\n \n\nCompliance: As detailed in the Requirement Documents.\n\n \n\nBackground: This Directive is amended in order to reference the latest amendment to the FAA AD 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","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":false,"description":"The instrument's stated amendment updates the reference to the latest amendment of the FAA AD requirement document (\"Background: This Directive is amended in order to reference the latest amendment to the FAA AD requirement document.\"). The directive continues to require inspections per the listed Requirement Documents and does not itself introduce new inspection types or expand the listed engine applicability. Therefore the substantive scope of who must comply and the type of inspection required is unchanged; the amendment updates which external document is the operative reference."},"complexity_factors":["Relies on external technical documents for the operative requirements rather than containing full procedures itself (\"Document\"; \"Compliance: As detailed in the Requirement Documents.\").","References multiple alternative Requirement Documents (Pratt & Whitney Alert SB No. 4854 Rev. 1; FAA AD 78-08-13 as amended; AD/PW-T/45A), requiring users to check which document applies and which amendment is current (\"Document\").","Technical subject matter (main gearbox magnetic plug inspection) requires specialised maintenance skills and equipment not described in the directive (title and applicability indicate technical scope).","Applicability is engine-model specific, so operators must identify covered engines precisely (\"Applicability: JT9D-3, -3A, -7, -7A, -7H, -7AH, 7A(SP), -7F, -7J.\").","The directive text amends references to a foreign regulator's AD (FAA), creating a cross-jurisdictional dependency and the need to track foreign amendments (\"Background\").","The directive does not quantify timing, intervals, or costs, so implementers must consult the Requirement Documents to determine operational impact (\"Compliance\")."],"plain_english_summary":"This AD requires owners/operators and maintenance organisations of specified Pratt & Whitney JT9D-engined aircraft to inspect the main gearbox magnetic plug in accordance with one of the referenced Requirement Documents (Pratt & Whitney ASB, FAA AD, or CASA AD). It matters because CASA updated the directive to reference the latest FAA AD; the technical steps, intervals, and corrective actions are contained in those external documents, and compliance costs/restraints fall to operators."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a minor amendment to an existing Airworthiness Directive. The scope remains identical to the original 1980 directive — it still applies to the same engine models and requires the same magnetic plug inspections. The only change is updating the reference to the latest FAA amendment (39-3710) to ensure Australian operators follow current international standards."},"complexity_factors":["Very short document (approximately 200 words)","Only 3 substantive paragraphs (Applicability, Document, Compliance)","No defined terms section","No conditional logic or nested exceptions","Simple cross-referencing to external technical documents rather than internal legislative structure","Single amendment note explaining the change"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA). It requires owners and operators of specific Pratt & Whitney JT9D jet engines to inspect the **main gearbox assembly** using **magnetic plugs** (specialised drain plugs that collect metal particles to detect internal wear or damage).\n\n**Who it affects:**\n- Operators of aircraft with JT9D-3, -3A, -7, -7A, -7H, -7AH, 7A(SP), -7F, or -7J engines\n- Maintenance organisations servicing these engines\n\n**What it requires:**\n- Inspection of the main gearbox magnetic plugs following specific procedures in referenced documents (Pratt & Whitney Service Bulletin 4854 Rev. 1, or FAA AD 78-08-13 as amended, or the previous Australian directive AD/PW-T/45A)\n- Compliance with whichever document the operator chooses to follow\n\n**Why it matters:**\nThis directive was **amended** to update the reference to the latest US Federal Aviation Administration (FAA) safety requirements. Magnetic plug inspections are critical for detecting metal contamination early — a warning sign of impending gearbox failure that could cause engine shutdown or catastrophic damage.\n\n**Key point:** This is a **revision** (2/80) of an existing directive, not a new requirement. The only change is updating the reference document to match current FAA standards."}},"importantCases":[],"_links":{"self":"/api/acts/ad-jt9d-10-main-gearbox-assembly-magnetic-plug-inspection","history":"/api/acts/ad-jt9d-10-main-gearbox-assembly-magnetic-plug-inspection/history","analysis":"/api/acts/ad-jt9d-10-main-gearbox-assembly-magnetic-plug-inspection/analysis","conflicts":"/api/acts/ad-jt9d-10-main-gearbox-assembly-magnetic-plug-inspection/conflicts","importantCases":"/api/acts/ad-jt9d-10-main-gearbox-assembly-magnetic-plug-inspection/important-cases","documents":"/api/acts/ad-jt9d-10-main-gearbox-assembly-magnetic-plug-inspection/documents"}}