{"id":"F2006B08475","name":"AD/CF6/32 - Oil Quantity and Flame Arrestor Plug","slug":"ad-cf6-32-oil-quantity-and-flame-arrestor-plug","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":51144,"registerId":"commonwealth-F2006B08475-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/CF6/32 - Oil Quantity and Flame Arrestor Plug","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/CF6/32 Oil Quantity and Flame Arrestor Plug 2/95\n\nApplicability: CF6-80C2 Engines.\n\nRequirement: Action in accordance with the technical requirements of FAA AD 94-20-06.\n\nNote: General Electric Service Bulletin 72-648 Revision 1 of 11 January1993 refers.\n\nCompliance: As specified in the FAA AD with an effective date of 2 February 1995.\n\nBackground: This Directive requires repetitive oil quantity checks after engine start-up before taxi and the installation of a flame arrestor plug in the aft end of the centre vent tube as terminating action to the repetitive oil quantity checks. These actions are prompted by three reports of uncontained engine failure when fire from fuel contamination in the oil systems caused separation of fan mid-shafts.","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The directive maintains a narrowly focused scope: it targets CF6-80C2 engines and prescribes repetitive oil-quantity checks with the option to remove that requirement by installing a flame arrestor plug, as referenced to FAA AD 94-20-06 and GE Service Bulletin 72-648 Rev 1 (Applicability; Requirement; Background; Note). There is no indication in the text supplied that the scope extends beyond those engines or beyond the described checks and terminating action."},"complexity_factors":["Narrow technical scope: applies only to CF6-80C2 engines (Applicability).","Cross-reference dependency: mandates following FAA AD 94-20-06 and GE Service Bulletin 72-648 Rev 1 for technical detail (Requirement; Note).","Operational vs modification paths: requires repetitive operational checks until a one-off hardware installation (Background).","Implementation reliance on external documents for parts, procedures and timing (Requirement; Note; Compliance).","Safety-critical timing: immediate operational procedures (pre-taxi checks) create day‑to‑day compliance needs (Background)."],"plain_english_summary":"Applies to aircraft with GE CF6-80C2 engines: operators must perform repeated oil-quantity checks after start and before taxi until a flame‑arrestor plug is fitted per FAA AD 94‑20‑06 and GE Service Bulletin 72‑648 Rev 1. The measures aim to stop uncontained failures caused by fuel‑contaminated oil. Costs fall to operators and MROs; the directive creates a clear incentive to fit the plug and relies on the FAA AD and GE bulletin for technical detail."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted safety directive addressing a specific mechanical failure mode in a specific engine series. It has not expanded beyond its original purpose of preventing uncontained engine failures due to oil system contamination."},"complexity_factors":["Very short document (approximately 150 words)","Only 1 defined term implicitly referenced (FAA AD 94-20-06)","No nested conditional logic — simple two-step requirement (checks + installation)","Single cross-reference to US FAA directive and one GE service bulletin","Clear applicability statement (specific engine model only)","No exceptions or exemptions listed"],"plain_english_summary":"**What this is:** This is an Airworthiness Directive (AD) — essentially a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) for aircraft engines.\n\n**What it does:** It requires airlines and aircraft operators using General Electric CF6-80C2 jet engines to:\n- **Check oil levels repeatedly** after starting the engine but before taxiing (moving the aircraft on the ground)\n- **Install a special safety plug** (called a \"flame arrestor plug\") at the back end of the centre vent tube — this plug acts as a permanent fix that stops the need for the repetitive oil checks\n\n**Why it matters:** Three engines had suffered catastrophic \"uncontained failures\" — meaning engine parts broke through the engine casing and flew out. The cause was fire from fuel contaminating the oil system, which then damaged the fan mid-shafts (central spinning shafts). This directive prevents engines from exploding and potentially endangering passengers, crew, and people on the ground.\n\n**Who must comply:** Anyone operating aircraft with CF6-80C2 engines — these are commonly used on Boeing 747, 767, and Airbus A300/A310 aircraft. Operators must follow the technical requirements of the equivalent US Federal Aviation Administration (FAA) directive (AD 94-20-06).\n\n**Key point:** This is a \"terminating action\" directive — the repetitive checks are temporary until the permanent fix (the flame arrestor plug) is installed."}},"importantCases":[],"_links":{"self":"/api/acts/ad-cf6-32-oil-quantity-and-flame-arrestor-plug","history":"/api/acts/ad-cf6-32-oil-quantity-and-flame-arrestor-plug/history","analysis":"/api/acts/ad-cf6-32-oil-quantity-and-flame-arrestor-plug/analysis","conflicts":"/api/acts/ad-cf6-32-oil-quantity-and-flame-arrestor-plug/conflicts","importantCases":"/api/acts/ad-cf6-32-oil-quantity-and-flame-arrestor-plug/important-cases","documents":"/api/acts/ad-cf6-32-oil-quantity-and-flame-arrestor-plug/documents"}}