{"id":"F2006B10994","name":"AD/JT8D/40 - Compressor Rotor - Removal from Service","slug":"ad-jt8d-40-compressor-rotor-removal-from-service","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":56584,"registerId":"commonwealth-F2006B10994-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.001.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 CASR 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.\n\n![](image.001.png)  \n\nPratt and Whitney Turbine Engines \\- JT8D Series","sortOrder":0},{"sectionNumber":"AD/JT8D/40 Compressor Rotor - Removal fr","sectionType":"part","heading":"AD/JT8D/40 Compressor Rotor - Removal from Servic e 8/2003","content":"# AD/JT8D/40 Compressor Rotor \\- Removal from Servic e 8/2003\n\nApplicability: Pratt and Whitney JT8D-1, \\-1A,-1B,-7,-7A,-7B,-9,-9A,-11,-15,-15A,-17,-17A,-17R\n\nand \\-17AR engines.\n\n| Requirement: | 1.  | Remove from service compressor rotor parts identified in paragraphs (a)(1), (a)(2) and (a)(3) of the requirement document, FAA AD 2003-05-07 Amdt 39- 13083.                                                  |\n| ------------ | --- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n|              | 2.  | Incorporate parts identified in paragraph (a)(4) of the requirement document.                                                                                                                                 |\n|              | 3.  | Do not install parts identified in paragraph (b) of the requirement document.                                                                                                                                 |\n| Compliance:  | 1.  | Requirement 1: At the next accessibility of the Low Pressure Compressor (LPC).                                                                                                                                |\n|              |     | For the purpose of this directive, accessibility means removal of the LPC from the engine and disassembly that provides piece-part exposure to the parts listed in paragraph (a) of the requirement document. |\n|              | 2.  | Requirement 2: At the next accessibility of the LPC.                                                                                                                                                          |\n|              | 3.  | Requirement 3: From the effective date of this directive.                                                                                                                                                     |\n\nThis Airworthiness Directive becomes effective on 7 August 2003.\n\nBackground: This directive is prompted by two reports of uncontained turbine failures following separation of fan section from the LPC.\n\n![Signature of Jim Coyne Delegate of the Civil Aviation Safety Authority](image.002.png)  \n\nJim Coyne\n\nDelegate of the Civil Aviation Safety Authority 26 June 2003\n\n![](image.001.png)","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":3,"scope_assessment":{"changed":false,"description":"This is a standard airworthiness directive with a focused, single-issue scope. It addresses a specific mechanical defect in specific engine models without expanding beyond its original safety purpose."},"complexity_factors":["Short, single-purpose directive with only 3 requirements","Heavy reliance on external reference (FAA AD 2003-05-07 Amdt 39-13083) — operators must cross-reference US regulations to identify specific part numbers","One defined term ('accessibility') with a technical explanation","No nested exceptions or conditional logic beyond the phased compliance dates","Narrow applicability — only 14 specific engine models affected"],"plain_english_summary":"This CASA safety order requires operators of Pratt & Whitney JT8D-series engines (used on older Boeing 727/737 and DC‑9/MD‑80 aircraft) to remove specified Low Pressure Compressor rotor parts at the next engine accessibility, fit replacement parts meeting updated specs, and stop installing certain parts immediately (effective 7 Aug 2003). It responds to two uncontained failures where fan/compressor separation caused debris release, and prevents further catastrophic engine damage or risk to aircraft and occupants."},"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":false,"description":"The AD is narrowly targeted at a specific unsafe condition (compressor-rotor parts in specified JT8D engines) and prescribes remedial parts actions. It does not broaden obligations beyond removing, replacing, and prohibiting particular parts tied to that condition. The directive follows the typical corrective scope for an airworthiness directive and does not materially expand the regulatory reach beyond its stated safety purpose."},"complexity_factors":["Short standalone AD with a single clear safety action (remove/incorporate/ban) — simpler than multi-part regulatory instruments","Cross-reference to FAA AD 2003-05-07 for the detailed part lists rather than reproducing part numbers increases implementation complexity","One explicitly defined term: 'accessibility' (defined in Compliance), which reduces ambiguity about the compliance trigger","Different timing rules for the three actions (two actions at 'next accessibility', one immediate ban) introduce conditional logic","Applicability limited to a finite list of JT8D engine variants — narrow scope but requires accurate fleet identification","Reliance on external document paragraphs (a)(1)-(a)(4) and (b) rather than including the content introduces dependency and potential versioning issues"],"plain_english_summary":"**What this directive does (mechanically)**\n\n- This Airworthiness Directive (AD) orders specific compressor-rotor parts used on certain Pratt & Whitney JT8D turbofan engines to be removed from service, replaced with approved parts, and banned from future installation. (See \"Requirement\".)\n- The AD does not reproduce the exact part identifiers in full; it refers operators to the FAA AD 2003-05-07 (paragraphs (a)(1)–(a)(4) and (b)) for the lists of parts to remove, parts to incorporate, and parts prohibited from installation. (See \"Requirement\".)\n- Timing is tied to maintenance events: the removals and incorporations must be done at the next time the engine's Low Pressure Compressor (LPC) is made accessible — defined here as removal of the LPC from the engine and disassembly to give piece-part exposure. Parts prohibited from installation must not be installed from the directive's effective date (7 August 2003). (See \"Compliance\".)\n\n**Who this affects**\n\n- Operators, owners, and maintenance organisations working on Pratt & Whitney JT8D engines listed in the AD: JT8D-1, -1A, -1B, -7, -7A, -7B, -9, -9A, -11, -15, -15A, -17, -17A, -17R and -17AR. (See \"Applicability\".)\n- Aircraft operators that schedule LPC removals or shop visits will be directly affected because required parts work must be completed at the next LPC accessibility. Maintenance providers and parts suppliers are affected because they must source the approved replacement parts and ensure banned parts are not fitted. Regulatory/compliance staff must verify conformity during inspections. (See \"Requirement\" and \"Compliance\".)\n\n**Why it matters (stated reason and practical effect)**\n\n- The AD arises from reports of two uncontained turbine failures following separation of the fan section from the LPC. The AD’s stated safety purpose is to prevent the unsafe condition by removing vulnerable compressor-rotor parts and ensuring only approved parts are installed. (See \"Background\".)\n\n**How it changes behaviour and who pays**\n\n- Maintenance behaviour: mechanics must inspect part identity at LPC shop visits, remove any affected parts listed in the referenced FAA AD, and install the required replacement parts where necessary. They must also refuse to fit any parts on the FAA AD’s prohibition list from the AD effective date onward. (Requirement + Compliance.)\n- Financial effect: aircraft operators (and their maintenance budgets) bear the direct costs — part purchase, labour during the next LPC accessibility, and potential additional downtime if parts are scarce or replacements require extra work. Maintenance providers and parts suppliers bear operational and supply-chain adjustments. The regulator (CASA) administers compliance oversight.\n\n**Administrative and implementation notes**\n\n- The AD relies on a cross-reference to FAA AD 2003-05-07 for the detailed part lists; the CASA AD does not print those part numbers itself. That creates a dependence on correctly identifying and applying the FAA AD paragraphs referenced in the Requirement section.\n- The compliance trigger is the next LPC accessibility (defined in the AD), not a fixed calendar deadline. This ties required action to a maintenance event rather than to an immediate grounding, which mitigates sudden fleet-wide downtime but may delay hazard elimination until actual LPC work happens.\n\n**Trade-offs, costs, and risks to watch**\n\n- Costs and disruption are concentrated on operators of the listed JT8D models (who must pay for parts and labour). The safety benefit is concentrated in preventing the specific failure mode identified in the background. This is a concentrated benefit (to operators and passengers) and concentrated cost (to those same operators).\n- Supply risk: if approved replacement parts (the paragraphs in the FAA AD) are limited or back-ordered, operators may face scheduling delays and elevated costs.\n- Implementation risk: because the AD points to the FAA AD for exact part identifiers, errors or ambiguity in cross-referencing (or updates to the FAA AD) could complicate compliance checks and maintenance planning. The AD does define \"accessibility\" to reduce uncertainty about the trigger event. (See \"Compliance\".)\n- Opportunity cost: tying compliance to the \"next LPC accessibility\" defers removal of banned parts until scheduled work, which reduces immediate disruption but allows some time during which the unsafe part could remain in-service.\n\n**Where to look in the AD**\n\n- Applicability: lists the affected JT8D engine variants.\n- Requirement: sets out (1) removal of specified compressor rotor parts, (2) incorporation of specified parts, and (3) prohibition on installing certain parts — with the detailed part lists located in FAA AD 2003-05-07 (paragraph references cited in this AD).\n- Compliance: sets the timing — removals and incorporations at the next LPC accessibility; prohibition from the effective date (7 August 2003). The AD also defines \"accessibility\" for the LPC.\n\n(Notes: The AD is a maintenance-mandatory directive: it prescribes corrective parts action and a compliance trigger linked to a maintenance event. It relies on an external FAA AD to identify the exact parts affected, so implementers must consult that FAA document in tandem.)"}},"importantCases":[],"_links":{"self":"/api/acts/ad-jt8d-40-compressor-rotor-removal-from-service","history":"/api/acts/ad-jt8d-40-compressor-rotor-removal-from-service/history","analysis":"/api/acts/ad-jt8d-40-compressor-rotor-removal-from-service/analysis","conflicts":"/api/acts/ad-jt8d-40-compressor-rotor-removal-from-service/conflicts","importantCases":"/api/acts/ad-jt8d-40-compressor-rotor-removal-from-service/important-cases","documents":"/api/acts/ad-jt8d-40-compressor-rotor-removal-from-service/documents"}}