{"id":"F2006B10967","name":"AD/JT15D/4 Amdt 2 - Engine Overspeed Fuel Shut-Off System","slug":"ad-jt15d-4-amdt-2-engine-overspeed-fuel-shut-off-system","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":56542,"registerId":"commonwealth-F2006B10967-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/JT15D/4 Amdt 2 - Engine Overspeed Fuel Shut-Off System","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 Canada Turbine Engines \\- JT15D Series\n\nAD/JT15D/4\n\nAmdt 2\n\n  \nEngine Overspeed Fuel Shut-Off System 5/92\n\nApplicability: All JT15D engines.\n\nRequirement: 1. Modify the engine overspeed fuel shut-off control wire rope assembly in accordance with Pratt and Whitney Canada Service Bulletin Number 7288.\n\n2. Modify the engine overspeed fuel shut-off control linkage assembly in accordance with Pratt and Whitney Canada Service Bulletin Number 7306.\n\nNote: Transport Canada AD CF-91-37 refers.\n\nCompliance: 1. At the next engine disassembly which affords access to the affected parts, but no later than 31 December 1992.\n\n2. At the next engine overhaul.\n\nBackground: This Directive has been amended to reflect the introduction of PWC Service Bulletin No. 7306. SB 7306 supersedes SB 7281 as the requirement document for replacement of the engine overspeed fuel shut-off control linkage. This Directive now requires replacement of the overspeed control wire rope assembly in accordance with SB 7288, and replacement of the overspeed control linkage in accordance with SB 7306.","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"The amendment alters the procedural compliance documents: SB 7306 now supersedes SB 7281 as the required service bulletin for replacing the overspeed control linkage, and SB 7288 is required for the wire rope assembly. Applicability (all JT15D engines) and the mechanical objects to be modified remain the same; the change is to which manufacturer documents govern the required work (as stated in the Directive's Background)."},"complexity_factors":["Technical requirement tied to specific manufacturer service bulletins (SB 7288 and SB 7306) — compliance depends on following external technical documents","Timing conditions use operational triggers ('next engine disassembly', 'next engine overhaul') plus a fixed backstop date (31 December 1992)","Amendment history: replacement of one SB (7281) by another (7306) changes the authoritative compliance document","Cross-reference to a foreign regulator (Transport Canada AD CF-91-37) creates an additional external point of reference","Applicability is broad (all JT15D engines) but the directive targets specific parts, raising logistical coordination for operators"],"plain_english_summary":"This Airworthiness Directive requires owners/operators of Pratt & Whitney Canada JT15D engines to replace the engine overspeed fuel shut-off control wire rope assembly and the control linkage per Pratt & Whitney Canada Service Bulletins (SB 7288 and SB 7306). It applies to all JT15D engines, must be done at the next engine disassembly (but no later than 31 December 1992) and at the next engine overhaul, and amends earlier instructions by substituting SB 7306 for the previously referenced SB 7281."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is an amendment (Amdt 2) that updates technical requirements within the existing scope of the original AD/JT15D/4. The amendment simply swaps one service bulletin (SB 7281) for another (SB 7306) for the linkage assembly modification. The scope remains tightly focused on the original purpose: ensuring the engine overspeed fuel shut-off system functions safely. No expansion of affected parties, engine models, or safety objectives."},"complexity_factors":["Very short document (approximately 200 words)","Only 2 substantive requirements with clear, separate compliance deadlines","Minimal defined terms (only standard aviation terminology like 'overhaul' and 'disassembly')","Single cross-reference to a Canadian Transport Canada directive (CF-91-37) in a non-binding note","No nested conditions or exceptions — straightforward 'do X by Y' structure","Background section provides helpful context rather than additional legal obligations"],"plain_english_summary":"This AD from CASA mandates two safety modifications to Pratt & Whitney Canada JT15D turbine engines—upgrading the wire rope assembly that actuates the fuel shut‑off for overspeed protection and replacing the associated linkage assembly—to ensure the automatic fuel shut‑off works correctly and prevents catastrophic engine overspeed.\n\nIt affects owners, operators and maintainers of JT15D‑powered aircraft; the wire rope must be done by next engine strip or by 31 Dec 1992, and the linkage at the next full overhaul."}},"importantCases":[],"_links":{"self":"/api/acts/ad-jt15d-4-amdt-2-engine-overspeed-fuel-shut-off-system","history":"/api/acts/ad-jt15d-4-amdt-2-engine-overspeed-fuel-shut-off-system/history","analysis":"/api/acts/ad-jt15d-4-amdt-2-engine-overspeed-fuel-shut-off-system/analysis","conflicts":"/api/acts/ad-jt15d-4-amdt-2-engine-overspeed-fuel-shut-off-system/conflicts","importantCases":"/api/acts/ad-jt15d-4-amdt-2-engine-overspeed-fuel-shut-off-system/important-cases","documents":"/api/acts/ad-jt15d-4-amdt-2-engine-overspeed-fuel-shut-off-system/documents"}}