{"id":"F2006B10984","name":"AD/JT8D/25 Amdt 1 - Combustion Chamber Outer Case Incomplete Weld","slug":"ad-jt8d-25-amdt-1-combustion-chamber-outer-case-incomplete-weld","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":56570,"registerId":"commonwealth-F2006B10984-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/JT8D/25 Amdt 1 - Combustion Chamber Outer Case Incomplete Weld","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 106 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nPratt and Whitney Turbine Engines \\- JT8D Series\n\nAD/JT8D/25\n\nAmdt 1\n\n  \nCombustion Chamber Outer Case Incomplete Weld 13/95\n\nApplicability: All JT8D engines with combustion chamber outer case (CCOC), Part Number 796761 or 806675, affected serial numbers as identified in P&W Alert Service Bulletin No 5842, Revision 3, dated October 1990.\n\nRequirement: Inspect part number 796761 and 806675 combustion chamber outer cases for cracks or incomplete welds adjacent to the rear flange, in accordance with the requirements of P&W Alert Service Bulletin No 5842, Revision 3, dated October 1990.\n\nNote: FAA AD 94-25-07 refers and supersedes FAA AD T89-05-52.\n\nCompliance: Effective 7 December 1995: Unless previously accomplished, as detailed in the Requirement Document.\n\nBackground: The original Directive required inspection of certain JT8D combustion chamber outer cases following advice of the failure of two cases in service. The failures initiated from an area of incomplete weld during manufacture. Undetected cracking of the combustion chamber outer case, could result in an uncontained engine failure.\n\nThis amendment allows only ultrasonic inspections and supersedes the original AD which allowed visual or fluorescent magnetic penetrant inspections (FMPI) under certain conditions.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This amendment narrows rather than expands the original scope. It restricts inspection methods to ultrasonic only, removing the alternative visual/FMPI options. The core safety purpose — detecting defective combustion chamber outer cases — remains unchanged."},"complexity_factors":["Short, single-purpose instrument (approximately 250 words)","Only 2 defined part numbers and 1 referenced technical document (P&W Alert Service Bulletin No 5842)","Simple conditional structure: applicability → requirement → compliance deadline","No nested exceptions or complex cross-referencing to other legislation","Technical complexity is externalised to the referenced service bulletin rather than contained in the instrument itself"],"plain_english_summary":"This CASA Airworthiness Directive mandates inspection of the combustion chamber outer case on certain Pratt & Whitney JT8D engines (specific part/serial numbers per the service bulletin) to detect cracks or incomplete welds that could cause catastrophic casing failure. Amendment 1 tightens the requirement: only ultrasonic inspection is now permitted, replacing visual or FMPI checks. It follows two in-service failures and prevents potentially uncontained engine breakups that threaten aircraft and people."},"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"},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"The amendment narrows permitted inspection methods: the original directive allowed visual or fluorescent magnetic particle inspection (FMPI) under certain conditions, while this amendment requires ultrasonic inspection only and supersedes the original AD. Applicability (P/Ns and affected serial numbers) and the inspection objective (detect cracks/incomplete welds adjacent to the rear flange) remain the same (Requirement; Amendment paragraph)."},"complexity_factors":["Narrow technical applicability: specific part numbers and affected serial numbers referenced (Applicability; Requirement: P&W Alert Service Bulletin No 5842 Rev 3).","Change in inspection method: amendment mandates ultrasonic inspection only, eliminating visual and FMPI options (Amendment paragraph).","Procedural dependence on external document: the detailed inspection procedure and scope are set out in the P&W Alert Service Bulletin that the AD references (Requirement).","Safety consequence tightens mandatory action: the AD responds to in-service failures and warns that undetected cracking could lead to uncontained engine failure (Background).","Compliance timing language: an effective date and the phrase 'unless previously accomplished' control when operators must comply (Compliance).","Technical implementation: ultrasonic inspection requires specific equipment and techniques different from visual/FMPI methods (Amendment paragraph).","Limited administrative discretion: the AD prescribes method and references the service bulletin, leaving little regulator discretion in inspection technique (Requirement; Amendment)."],"plain_english_summary":"Requires ultrasonic inspection of specified Pratt & Whitney JT8D combustion chamber outer cases (P/N 796761 or 806675, affected serial numbers per P&W Alert Service Bulletin No 5842 Rev 3) for cracks or incomplete welds adjacent to the rear flange. Applies to engine owners/operators and maintenance organisations; noncompliance risks undetected cracking that could cause uncontained engine failure.\n\nThe amendment removes visual and FMPI options and restricts inspection to ultrasonic inspection, which may require different equipment and procedural time than the superseded methods."}},"importantCases":[],"_links":{"self":"/api/acts/ad-jt8d-25-amdt-1-combustion-chamber-outer-case-incomplete-weld","history":"/api/acts/ad-jt8d-25-amdt-1-combustion-chamber-outer-case-incomplete-weld/history","analysis":"/api/acts/ad-jt8d-25-amdt-1-combustion-chamber-outer-case-incomplete-weld/analysis","conflicts":"/api/acts/ad-jt8d-25-amdt-1-combustion-chamber-outer-case-incomplete-weld/conflicts","importantCases":"/api/acts/ad-jt8d-25-amdt-1-combustion-chamber-outer-case-incomplete-weld/important-cases","documents":"/api/acts/ad-jt8d-25-amdt-1-combustion-chamber-outer-case-incomplete-weld/documents"}}