{"id":"F2006B08481","name":"AD/CF6/39 - Accessory Gearbox Idler Adaptor - Inspection","slug":"ad-cf6-39-accessory-gearbox-idler-adaptor-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":51159,"registerId":"commonwealth-F2006B08481-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/CF6/39 - Accessory Gearbox Idler Adaptor - Inspection","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)  \nGeneral Electric Turbine Engines \\- CF6 Series\n\nAD/CF6/39 Accessory Gearbox Idler Adaptor \\- Inspection 3/99 TX\n\nApplicability: General Electric Company CF6 80C2 series turbofan engines with accessory gearbox (AGB) idler adapters, Part Number (P/N) 9395M78G08 that have been reworked from a P/N 9395M78G06 configuration using CF6-80C2 Service Bulletin (SB) 72- 743 dated 25 August 1994, excluding those parts that were repaired by GE Repair Document 032-273-S1 dated 18 April 1998.\n\nThese engines are installed on, but not limited to, Boeing 747 and 767, Airbus 300 and 310, McDonnell Douglas MD-11 Series aircraft.\n\nNote: Methods of determining if a (P/N) 9395M78G08 AGB has been reworked from a P/N 9395M78G06 configuration include a record search or a visual inspection of the AGB idler adapter in accordance with GE CF6-80C2 Alert Service Bulletin (ASB) 73-A283 Revision 2 dated 18 November 1998, Revision 1 dated 30 October 1998 or\n\nOriginal dated 18 September 1998.\n\nRequirements: 1. Unless already accomplished perform a visual inspection of AGB idler adapter inserts in accordance with paragraph (2)(B) of the Accomplishment Instructions of GE CF6-80C2 Alert Service Bulletin (ASB) 73-A283 Revision 2 dated 18 November 1998, Revision 1 dated 30 October 1998 or Original dated 18\n\nSeptember 1998.\n\n2. Remove the AGB adapters from service and replace adapters with one or more inserts that are flush with or extend past the back face of the casing with serviceable parts.\n\nCompliance: 1. Within 10 days after the effective date of this Directive.\n\n2. Subject to the outcome of the inspection at Requirement 1, before further flight.\n\nNote: US FAA AD 99-01-01 Amendment 39-10968 refers.\n\nThis Airworthiness Directive becomes effective on 4 February 1999.\n\nBackground: This Directive is raised to identify unserviceable AGB idler adapter inserts. A recent incident was reported where a fuel tube flange connection to improper AGB idler adapter inserts resulted in a high pressure fuel leak and engine fire. This Directive reflects a country of origin AD.","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The Directive stays within the original safety-focused purpose: identify and remove unserviceable AGB idler adapter inserts on a narrowly defined set of CF6-80C2 engines. It implements the manufacturer/FAA-origin remedy without materially expanding coverage beyond the engines/parts and circumstances described in the source AD and the referenced service documents."},"complexity_factors":["Short document with a narrow technical focus (single part number and rework history)","References to multiple external manufacturer documents (GE ASB 73-A283 revisions and GE SB 72-743) for inspection procedures","Exclusion clause for parts repaired under GE Repair Document 032-273-S1 (requires checking repair history)","Two-step conditional requirement: inspect within 10 days, then replace before further flight if defects found","Cross-reference to a US FAA AD","Ambiguous term 'serviceable parts' left to maintenance standards and referenced documents rather than defined in the Directive"],"plain_english_summary":"**What this directive does (in plain English)**\n\n- This is an Airworthiness Directive (an enforceable safety order) that applies to certain General Electric CF6-80C2 aircraft engines fitted with a particular accessory gearbox (AGB) idler adapter, Part Number 9395M78G08, but only when that part has previously been reworked from an earlier configuration (P/N 9395M78G06) using a specific GE Service Bulletin. Engines with that P/N which were repaired in accordance with a particular GE repair document (032-273-S1 dated 18 April 1998) are excluded. (Applicability)\n\n- Operators must check whether their AGB idler adapter inserts are unserviceable by doing either a records search or a visual check following the GE Alert Service Bulletin (ASB) referenced in the Directive. (Applicability / Note)\n\n- If not already inspected, operators must do a visual inspection of the AGB idler adapter inserts in accordance with the GE ASB cited. (Requirements 1)\n\n- If the inspection shows the adapter insert(s) are not acceptable, the AGB adapter(s) must be removed from service and replaced with \"serviceable parts\" (i.e. parts that meet the required condition) before the aircraft flies again. (Requirements 2 / Compliance 2)\n\n- The visual inspection must be completed within 10 days of the Directive coming into effect. If removal/replacement is needed, that must be done before further flight. (Compliance)\n\n- The Directive refers to a U.S. FAA AD and to specific GE service documents for the exact inspection steps. (Note / Requirements)\n\n\nWhy the Directive was issued (source's stated reason)\n\n- The Directive was raised after an incident where an improper AGB idler adapter insert led to a fuel-tube flange connection failure, a high‑pressure fuel leak and an engine fire. The Directive intends to identify and remove unserviceable AGB idler adapter inserts. (Background)\n\n\nPractical effects, who pays, and who decides\n\n- Who pays: Aircraft operators and owners bear the direct costs — performing the inspection, grounding the aircraft while work is done, and buying/replacing adapters if required. Maintenance organisations will incur labour and parts costs; insurers may be involved depending on cover. (Requirements / Compliance)\n\n- Who decides: The Civil Aviation Safety Authority (CASA) enforces compliance with the Directive. The onus is on operators to follow the inspection steps in the GE ASB and to determine serviceability (Applicability / Requirements). The manufacturer's ASB supplies the technical method for the inspection. (Applicability / Requirements)\n\n- What behaviour changes: Operators must (a) check records or visually inspect AGB idler adapters for the specific P/N and rework history, (b) carry out the prescribed visual inspection within 10 days, and (c) remove and replace any adapters with non-conforming inserts before flying that aircraft again. (Requirements / Compliance)\n\n\nTrade-offs, incentives and implementation issues to note\n\n- The Directive references manufacturer paperwork (GE ASB/SB) for inspection technique and a GE repair document for an exclusion. That centralises the technical remedy with the OEM's maintenance guidance. Operators will need access to those documents and to any approved replacement parts.\n\n- The short compliance window (10 days) can cause operational disruption if many engines are affected or if replacement adapters are not immediately available; this is a predictable trade-off between rapid risk mitigation and aircraft downtime. (Compliance)\n\n- The Directive is narrowly targeted by part number, rework history and repair-exclusion; it does not impose fleet-wide actions beyond that set of engines/parts. (Applicability)\n\n- The Directive relies on operators to determine rework history either from records or by visual inspection. That creates modest administrative burden (record searches) and some judgement calls for maintenance staff following the referenced ASB. (Applicability / Note)\n\n\nReference sections used: Applicability (which engines/parts are covered and how to tell), Requirements (inspection and replacement), Compliance (timing), Background (reason for issuing)."},"kimi_summary":{"content_quality":"ok","complexity_score":4,"scope_assessment":{"changed":false,"description":"This Airworthiness Directive maintains its original narrow scope. It addresses a specific safety defect in a specific engine part identified after an incident. The detailed applicability criteria (specific part numbers, specific rework history, specific repair exclusions) keep the directive tightly focused on the exact configuration that poses a risk, without expanding beyond the original safety purpose."},"complexity_factors":["Highly specific part number targeting (P/N 9395M78G08 reworked from P/N 9395M78G06)","Multiple document references requiring cross-checking (Service Bulletin 72-743, Alert Service Bulletin 73-A283 with three different revision dates, GE Repair Document 032-273-S1)","Nested applicability conditions: must meet part number criteria AND specific rework history AND exclusion for certain repair dates","Two-stage compliance with conditional logic (Requirement 2 only triggered by outcome of Requirement 1)","Technical aviation terminology throughout (AGB, idler adapter, turbofan, serviceable parts)"],"plain_english_summary":"This airworthiness safety order requires operators of CF6-80C2-powered aircraft to inspect a specific accessory gearbox idler adapter — but only units modified per a 1994 service bulletin — within 10 days and to replace any adapters with improperly protruding inserts before the airplane returns to service. It affects airlines, maintenance crews, and operators of affected Boeing, Airbus, and MD‑11 types and aims to prevent fuel leaks and engine fires."},"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"}},"importantCases":[],"_links":{"self":"/api/acts/ad-cf6-39-accessory-gearbox-idler-adaptor-inspection","history":"/api/acts/ad-cf6-39-accessory-gearbox-idler-adaptor-inspection/history","analysis":"/api/acts/ad-cf6-39-accessory-gearbox-idler-adaptor-inspection/analysis","conflicts":"/api/acts/ad-cf6-39-accessory-gearbox-idler-adaptor-inspection/conflicts","importantCases":"/api/acts/ad-cf6-39-accessory-gearbox-idler-adaptor-inspection/important-cases","documents":"/api/acts/ad-cf6-39-accessory-gearbox-idler-adaptor-inspection/documents"}}