{"id":"F2007L00003","name":"AD/CFM56/24 - Fuel Filters Manufactured by Western Filters or PTI Technologies","slug":"ad-cfm56-24-fuel-filters-manufactured-by-western-filters-or-pti-technologies","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":67963,"registerId":"commonwealth-F2007L00003-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"CFM International Turbine Engines - CFM5","sectionType":"division","heading":"CFM International Turbine Engines - CFM56 Series","content":"### CFM International Turbine Engines - CFM56 Series\n\n| AD/CFM56/24 | Fuel Filters Manufactured by WesternFilters or PTI Technologies | 2/2007 TX |\n| ----------- | --------------------------------------------------------------- | --------- |\n\n| Applicability: | CFM International CFM56-2 series, -3 series, -5 series, and -7B series engines with fuel filters, Western Filter part numbers (P/Ns) WF337661 and WF337017 and PTI Technologies P/Ns 7595983-101 and 7588133, installed.                                                                                                                                                                                                                                                                                                                                                                                             |\n| -------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | 1. CFM56-7B engines: Replace fuel filter, Western Filter P/Ns WF337661 or WF337017 and PTI Technologies P/Ns 7595983-101 or 7588133, with a filter that has a P/N not listed in this AD.2. CFM56-2 series, -3 series, and -5 series engines: Replace fuel filter, Western Filter P/Ns WF337661 or WF337017 and PTI Technologies P/Ns 7595983- 101 or 7588133, with a filter that has a P/N not listed in this AD.3. Do not install any fuel filter, Western Filter P/Ns WF337661 or WF337017 or PTI Technologies P/Ns 7595983-101 or 7588133.Note: FAA Airworthiness Directive 2006-26-01 Amendment 39-14859 refers. |\n| Compliance:    | 1. Within 600 flight hours or 60 days after the effective date of this AD, whichever occurs first,2. At the next filter change or 4,000 flight hours, whichever occurs first, after the effective date of this AD,3. After the effective date of this AD.                                                                                                                                                                                                                                                                                                                                                            |\n|                | This Airworthiness Directive becomes effective on 3 January 2007.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |\n| Background:    | This AD results from 12 reports of failed fuel filters.Failure of fuel filters may result in loss of engine thrust, which in turn, may result in loss of aircraft control during takeoff or landing.                                                                                                                                                                                                                                                                                                                                                                                                                 |\n\n![](image.001.png)  \nJames Coyne  \nDelegate of the Civil Aviation Safety Authority\n\n2 January 2007","sortOrder":0},{"sectionNumber":"AD/CFM56/24","sectionType":"part","heading":"AD/CFM56/24","content":"## AD/CFM56/24","sortOrder":1},{"sectionNumber":"Fuel Filters Manufactured by WesternFilt","sectionType":"part","heading":"Fuel Filters Manufactured by WesternFilters or PTI Technologies","content":"## Fuel Filters Manufactured by Western  \nFilters or PTI Technologies","sortOrder":2},{"sectionNumber":"2/2007 TX","sectionType":"part","heading":"2/2007 TX","content":"## 2/2007 TX","sortOrder":3}],"analysis":{"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The instrument remains narrowly targeted to a specific airworthiness safety issue: removal and prohibition of particular fuel-filter part numbers on defined CFM56 engine models. It does not expand the regulatory scope beyond that original corrective purpose (no new continuing-obligation regimes, no broadened categories of parts or aircraft)."},"complexity_factors":["Short, single-issue instrument focused on specified fuel-filter part numbers","Four affected part numbers (two Western Filters, two PTI Technologies)","Four engine-series applicability groups (CFM56-2, -3, -5, -7B) but the action is uniform across groups","Three compliance time buckets (600 flight hours/60 days; next filter change/4,000 flight hours; immediate prohibition of installation)","No nested exceptions or extensive definitions","One cross-reference to FAA AD; no large web of cross-references to other domestic legislation"],"plain_english_summary":"**What this instrument does**\n\n- Requires operators to remove and replace certain fuel filters made by Western Filters or PTI Technologies that are fitted to CFM56 family engines (CFM56-2, -3, -5 and -7B).  The affected part numbers are Western Filter P/Ns WF337661 and WF337017, and PTI Technologies P/Ns 7595983-101 and 7588133. (Applicability / Requirement)\n\n- Bans future installation of those exact part numbers. (Requirement)\n\n**Who is affected**\n\n- Aircraft operators and owners who have CFM56-2, -3, -5 or -7B engines with the listed fuel-filter part numbers installed.  \n- Maintenance organisations and licensed engineers who carry out filter changes and certify compliance.  \n- Parts suppliers and filter manufacturers: suppliers of the affected parts will lose the ability to have those parts installed, while makers of alternative approved filters may see increased demand. (Applicability / Requirement)\n\n**What you must do and when**\n\n- For CFM56-7B engines: replace any affected filter with a filter having a part number that is NOT one of the four affected P/Ns within 600 flight hours or within 60 days of the AD taking effect, whichever comes first. (Requirement 1; Compliance 1)\n\n- For CFM56-2, -3 and -5 engines: replace any affected filter with a filter having a part number that is NOT one of the four affected P/Ns at the next scheduled filter change or within 4,000 flight hours after the AD takes effect, whichever occurs first. (Requirement 2; Compliance 2)\n\n- Do not install any of the affected Western or PTI filter part numbers after the AD takes effect. (Requirement 3; Compliance 3)\n\n- The AD took effect on 3 January 2007. (Compliance)\n\n**Why the change was imposed (source claim)**\n\n- The issuing authority records 12 reports of failed fuel filters.  The AD states that filter failure may cause loss of engine thrust and thereby risk loss of aircraft control during critical phases such as takeoff or landing. (Background)\n\n**Practical consequences, incentives and trade-offs**\n\n- Who pays: aircraft operators (or their lessors) pay for replacement filters, labour and associated downtime.  Replacement cost is a direct operating cost; more aircraft affected increases aggregate cost to the operator community. (Requirement / Compliance)\n\n- Who decides: operators and maintenance organisations decide timing and which approved replacement part to fit, subject to the mandatory deadlines in the AD. The regulator enforces compliance through continuing airworthiness oversight. (Requirement / Compliance)\n\n- Behaviour changes: maintenance programmes must be checked to identify affected engines and parts, schedule replacements within the specified windows, and prevent re‑installation of the banned P/Ns. Record-keeping and parts-control procedures must be updated accordingly. (Requirement / Compliance)\n\n- Market effects: demand shifts to alternative approved filter part numbers. Suppliers of the removed part numbers lose prospective sales for these engines; suppliers of alternative approved filters gain orders. If approved alternatives are limited in supply, operators face risk of operational disruption or short‑term cost increases. (Requirement)\n\n- Trade-offs and implementation risk: the AD reduces the reported safety risk at the cost of procurement, logistic and downtime expenses. There is a risk of non-compliance if parts are misidentified in inventory, or if replacement parts are not available promptly; this could increase enforcement activity or force flight cancellations. (Background / Compliance)\n\n**Mechanics for operators**\n\n- Inspect maintenance records/parts inventories to identify affected filters and engines (Applicability).  \n- Schedule and perform replacements within the timeframe tied to engine model group (Compliance).  \n- Ensure no future installation of the four specified P/Ns on the covered engines (Requirement 3).\n\n**Reference note**\n\n- The AD cites an FAA Airworthiness Directive (2006-26-01) as related material; operators commonly cross-check such references for technical detail and approved replacement parts. (Requirement note)\n"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard, targeted airworthiness directive addressing a specific safety defect in specific aircraft components. The scope remains precisely limited to the identified faulty fuel filters and affected engine types, consistent with the original purpose of aviation safety regulation."},"complexity_factors":["Very short document (approximately 300 words)","Only 4 specific part numbers to identify","Clear, unambiguous compliance deadlines with simple alternatives ('whichever occurs first')","No defined terms section or interpretation provisions","No cross-references to other legislation (only a reference to related FAA directive in a note)","Straightforward applicability table with specific engine series listed","Simple three-part requirement structure with no nested conditions or exceptions"],"plain_english_summary":"CASA has issued a mandatory Airworthiness Directive requiring removal and replacement of certain faulty fuel filters made by Western Filters and PTI installed in CFM56-2, -3, -5 and -7B engines (used on Boeing 737 and Airbus A320 families). It affects airlines, maintenance organisations and anyone responsible for these engines.\n\nThe AD sets short replacement deadlines (600 flight hours/60 days for -7B; next scheduled change or 4,000 fh for others) and prohibits future installation — prompted by 12 filter failures that risk sudden engine power loss."},"flash_summary_failed":{"failed":true,"reason":"A positive credit balance is required for all requests, including BYOK, so fallback providers remain available. Add credits at https://vercel.com/d?to=%2F%5Bteam%5D%2F%7E%2Fai%3Fmodal%3Dtop-up to continue.","source":"analysis-cron"}},"importantCases":[],"_links":{"self":"/api/acts/ad-cfm56-24-fuel-filters-manufactured-by-western-filters-or-pti-technologies","history":"/api/acts/ad-cfm56-24-fuel-filters-manufactured-by-western-filters-or-pti-technologies/history","analysis":"/api/acts/ad-cfm56-24-fuel-filters-manufactured-by-western-filters-or-pti-technologies/analysis","conflicts":"/api/acts/ad-cfm56-24-fuel-filters-manufactured-by-western-filters-or-pti-technologies/conflicts","importantCases":"/api/acts/ad-cfm56-24-fuel-filters-manufactured-by-western-filters-or-pti-technologies/important-cases","documents":"/api/acts/ad-cfm56-24-fuel-filters-manufactured-by-western-filters-or-pti-technologies/documents"}}