{"id":"F2006B11002","name":"AD/JT8D-200/4 - Number 4-1/2 Bearing Spacer","slug":"ad-jt8d-200-4-number-4-1-2-bearing-spacer","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":56596,"registerId":"commonwealth-F2006B11002-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/JT8D-200/4 - Number 4-1/2 Bearing Spacer","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-200 Series\n\n \n\nAD/JT8D-200/4 Number 4-1/2 Bearing Spacer 10/92\n\nApplicability: JT8D-209, -217, 217A, 217C and -219 turbofan engines.\n\nRequirement: As detailed in the technical requirements of FAA Airworthiness Directive 91-24-14. Compliance:              As detailed in the Requirement document, with an effective date of 17 September\n\n1992.\n\n \n\nBackground:  This Directive requires the review of the number 4-1/2 bearing spacer purchase source.\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","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"This instrument adopts the technical requirements of FAA AD 91-24-14 for the listed JT8D-200 engine variants and limits its action to a review of the purchase source for the number 4-1/2 bearing spacer (Requirement; Background; Applicability). The text does not expand or narrow those requirements itself; it incorporates the FAA AD by reference and relies on that document for technical scope and compliance timing (Requirement; Compliance)."},"complexity_factors":["Narrow technical scope limited to a single component (number 4-1/2 bearing spacer) and specific engine variants (Applicability)","Incorporation by reference of an external FAA Airworthiness Directive (91-24-14) rather than standalone technical instructions (Requirement)","Absence of detailed remedial or inspection steps in this instrument — implementers must obtain and interpret the FAA AD (Requirement)","Defined compliance date in the referenced document adds an external timing dependency (Compliance)"],"plain_english_summary":"This Directive applies to specified Pratt & Whitney JT8D-200 variants and mandates compliance with FAA AD 91-24-14 (effective 17 Sep 1992) to review the purchase source of the No. 4-1/2 bearing spacer.\n\nOwners, operators and maintenance organisations must follow the FAA AD’s technical instructions and timing and bear any review or corrective costs. The Civil Aviation Safety Authority issues and enforces the Directive; specific inspection and corrective details are contained in the referenced FAA AD."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, single-issue airworthiness directive focused specifically on bearing spacer sourcing verification. It has not expanded beyond its original narrow safety purpose."},"complexity_factors":["Very short document (approximately 150 words)","Only 1 defined term implicitly referenced (the bearing spacer part number)","No nested conditional logic or exceptions","Single cross-reference to external FAA technical document (AD 91-24-14)","Straightforward applicability clause listing 5 specific engine models","No internal definitions section or interpretation provisions"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** issued by Australia's Civil Aviation Safety Authority (CASA) that applies to specific Pratt & Whitney jet engines used in aircraft.\n\n**What it does:**\n- Requires airlines and aircraft operators to check where they bought a specific engine part called the \"Number 4-1/2 Bearing Spacer\" for certain Pratt & Whitney JT8D-200 series engines.\n\n**Who it affects:**\n- Operators of aircraft with JT8D-209, -217, -217A, -217C, or -219 turbofan engines (these are commonly used in older Boeing 727 and MD-80 series aircraft).\n\n**Why it matters:**\n- This directive was issued because there were concerns about the quality or authenticity of bearing spacers from certain suppliers. The wrong spacer could cause engine failure, which is obviously catastrophic in flight. Operators must follow the technical instructions from the US Federal Aviation Administration (FAA) Directive 91-24-14 to ensure their engines are safe.\n\n**Key dates:**\n- The directive became effective on **17 September 1992**."}},"importantCases":[],"_links":{"self":"/api/acts/ad-jt8d-200-4-number-4-1-2-bearing-spacer","history":"/api/acts/ad-jt8d-200-4-number-4-1-2-bearing-spacer/history","analysis":"/api/acts/ad-jt8d-200-4-number-4-1-2-bearing-spacer/analysis","conflicts":"/api/acts/ad-jt8d-200-4-number-4-1-2-bearing-spacer/conflicts","importantCases":"/api/acts/ad-jt8d-200-4-number-4-1-2-bearing-spacer/important-cases","documents":"/api/acts/ad-jt8d-200-4-number-4-1-2-bearing-spacer/documents"}}