{"id":"F2006B06683","name":"AD/RRT-S/15 - Stage 2 Low Pressure Turbine Blades","slug":"ad-rrt-s-15-stage-2-low-pressure-turbine-blades","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":48696,"registerId":"commonwealth-F2006B06683-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"AIRWORTHINESS DIRECTIVE","sectionType":"part","heading":"AIRWORTHINESS DIRECTIVE","content":"# AIRWORTHINESS DIRECTIVE\n\n![](image.002.png)\n\nFor the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.1 (1) of CAR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.","sortOrder":0},{"sectionNumber":"AD/RRT-S/15 Stage 2 Low Pressure Turbine","sectionType":"part","heading":"AD/RRT-S/15 Stage 2 Low Pressure Turbine Blades 9/2001","content":"# ![](image.003.png)AD/RRT-S/15 Stage 2 Low Pressure Turbine Blades 9/2001\n\nApplicability: Rolls Royce Spey 555-15, \\-15H, \\-15N, and \\-15P engines.\n\nRequirement: Replace Stage 2 Low Pressure Turbine Blades in accordance with Rolls Royce Spey SB Sp72-1064 Revision 1 (Mod 6428).\n\nNote 1: CAA (UK) AD 005-07-2000 refers.\n\nNote 2: Compliance with original issue of SB Sp 72-1064 satisfies the intent of this AD.\n\nNote 3: This Requirement was previously addressed in AD/RRT-S/12 Amdt 2.\n\nCompliance: No later than 31 December 2005.\n\nThis Airworthiness Directive becomes effective on 6 September 2001.\n\nBackground: Stage 2 LPT blade failures continue to occur in service. This Directive mandates an improved blade that exhibits reduced stresses. This Directive supersedes AD/RRT- S/12 Amdt 2 which has been cancelled.\n\n![Signature of Eugene Paul Holzapfel Delegate of the Civil Aviation Safety Authority](image.004.png)  \n\nEugene Paul Holzapfel\n\nDelegate of the Civil Aviation Safety Authority 26 July 2001\n\n![](image.002.png)  \n\nThe above AD is notified in the Commonwealth of Australia Gazette on 15 August 2001.","sortOrder":1}],"analysis":{"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"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This AD maintains its original narrow scope. It supersedes a previous directive (AD/RRT-S/12 Amdt 2) on the same specific issue, but does not expand beyond the original purpose of addressing Stage 2 LPT blade failures in these specific Rolls Royce Spey engine variants."},"complexity_factors":["Single, specific technical requirement (blade replacement)","Only 4 engine models affected, clearly listed","One compliance deadline with no conditional exceptions","No nested definitions or interpretation sections","Cross-reference to only one external document (manufacturer's service bulletin)","Brief background explaining the safety rationale","Total length under 300 words"],"plain_english_summary":"This mandatory CASA order requires operators and maintainers of Rolls‑Royce Spey 555‑15/‑15H/‑15N/‑15P engines to replace Stage‑2 low‑pressure turbine blades with an improved design per the manufacturer’s service bulletin by 31 December 2005. It affects airlines, owners and maintenance organisations using these engines and aims to prevent continuing in‑service blade failures that can cause catastrophic engine damage and in‑flight emergencies."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"This AD supersedes AD/RRT‑S/12 Amdt 2 and mandates installation of an improved blade design via Rolls Royce SB Sp72‑1064 Rev 1 (Mod 6428), updating the corrective action required for the same engine models (Background; Requirement; Note 3)."},"complexity_factors":["Single clear technical action: mandatory replacement of Stage 2 LPT blades per a named Rolls Royce Service Bulletin (Requirement).","Incorporation by reference of an external manufacturer document (Sp72‑1064 Rev 1, Mod 6428) creates dependency on that SB for procedural detail (Requirement).","Limited set of affected engine models narrows operational scope but concentrates costs on operators of those types (Applicability).","Fixed compliance deadline introduces scheduling and logistical burden for maintenance planning (Compliance).","Legal lineage: supersedes and cancels a prior AD (AD/RRT‑S/12 Amdt 2), so operators must track regulatory history (Background; Note 3).","Cross‑reference to UK CAA AD may require operators to reconcile multiple authority instructions (Note 1)."],"plain_english_summary":"This Airworthiness Directive requires operators of Rolls Royce Spey 555-15, -15H, -15N and -15P engines to replace their Stage 2 low‑pressure turbine blades with the improved design specified in Rolls Royce Service Bulletin Sp72‑1064 Revision 1 (Mod 6428) by 31 December 2005 (Applicability; Requirement; Compliance). The Civil Aviation Safety Authority delegate issued the mandatory direction; affected operators pay for and arrange the replacements to reduce in‑service blade failures (Background; Requirement)."}},"importantCases":[],"_links":{"self":"/api/acts/ad-rrt-s-15-stage-2-low-pressure-turbine-blades","history":"/api/acts/ad-rrt-s-15-stage-2-low-pressure-turbine-blades/history","analysis":"/api/acts/ad-rrt-s-15-stage-2-low-pressure-turbine-blades/analysis","conflicts":"/api/acts/ad-rrt-s-15-stage-2-low-pressure-turbine-blades/conflicts","importantCases":"/api/acts/ad-rrt-s-15-stage-2-low-pressure-turbine-blades/important-cases","documents":"/api/acts/ad-rrt-s-15-stage-2-low-pressure-turbine-blades/documents"}}