{"id":"F2006B07822","name":"Airworthiness Directives 2004 - Revocation and Remaking - Coolers","slug":"airworthiness-directives-2004-revocation-and-remaking-coolers","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":50715,"registerId":"commonwealth-F2006B07822-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"Airworthiness Directives 2004 - Revocation and Remaking - Coolers","content":"---\nmeta-content-style-type: text/css\nmeta-content-type: application/xhtml+xml; charset=utf-8\nmeta-generator: Aspose.Words for .NET 20.2\n---\n\n?xml version=\"1.0\" encoding=\"utf-8\" standalone=\"no\"?>\n\n Airworthiness Directives 2004\n\n I, DAVID ALAN VILLIERS, delegate of the Civil Aviation Safety\n\n Authority, acting under subregulation 39.001 (1) of the Civil\n\n Aviation Safety Regulations 1998:\n\n (a) revoke the Airworthiness Directives mentioned in\n\n Schedule 1; and\n\n (b) make, as separate instruments, each Airworthiness\n\n Directive mentioned in Schedule 1 and attached.\n\n \n\n ![](image.001.png)\n\n David Villiers\n\n Delegate of the Civil Aviation Safety Authority\n\n \n\n  20 December 2004\n\n Note:   Each attached Airworthiness Directive is being re-made in exactly the\n\n same form as appears in the latest published edition of the Directive.\n\n \n\n\n Schedule 1 Revocation and Remaking of\n\n Airworthiness Directives\n\n Coolers\n\n AD Name AD Number\n\n Stewart Warner Oil Coolers - Inspection and Replacement AD/COOL/1\n\n Stewart Warner Oil Coolers - Inspection and Replacement AD/COOL/2\n\n \n","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The instrument does not change the substantive scope of regulatory obligations. It revokes the listed ADs and re-makes them in the same form as the latest published editions, so the technical and operational requirements imposed by those ADs remain unchanged (preamble; Note; Schedule 1)."},"complexity_factors":["Instrument is procedural: revocation and reissuance of existing ADs rather than creation of new substantive requirements (preamble; Note).","References a single statutory power (subregulation 39.001(1)) reducing cross-statutory linkage complexity (preamble).","Affected items are narrowly identified by name in Schedule 1 (two ADs), limiting scope and stakeholder range (Schedule 1).","Substantive content of ADs is unchanged according to the Note, so technical regulatory analysis beyond the AD texts is not required (Note).","Potential operational complexity lies in compliance costs (inspection/replacement) but those arise from the underlying ADs rather than from this procedural instrument (Schedule 1)."],"plain_english_summary":"# What this instrument does\n\nThis instrument is an administrative action by a delegate of the Civil Aviation Safety Authority (CASA) that formally revokes two listed Airworthiness Directives (ADs) and re-makes each of them as separate instruments. The delegate doing this is David Alan Villiers, acting under subregulation 39.001(1) of the Civil Aviation Safety Regulations 1998 (see preamble). The two ADs affected are the Stewart Warner Oil Coolers - Inspection and Replacement directives (AD/COOL/1 and AD/COOL/2) listed in Schedule 1.\n\n# Who this affects\n\n- Aircraft owners, operators and maintenance organisations that are subject to those two ADs (the ADs' titles identify the affected equipment: Stewart Warner oil coolers) (Schedule 1). \n- CASA and its delegate who exercise and record the regulatory action (preamble). \n\n# How it works mechanically\n\n- The delegate expressly revokes the ADs named in Schedule 1 and, at the same time, makes each of those ADs again \"as separate instruments\" (preamble). \n- A Note attached to the instrument states that each attached AD is being re-made \"in exactly the same form as appears in the latest published edition of the Directive.\" That indicates no substantive changes to the content of the ADs are being made by this action (Note). \n\n# Why it matters (official claim and practical implications)\n\n- Official claim: the instrument implements a revocation and re-making of the listed ADs under the delegated power in subregulation 39.001(1) (preamble). The accompanying Note states the re-made ADs are identical to the latest published editions. \n\n- Practical implications and trade-offs: because the AD names include \"Inspection and Replacement,\" compliance with those ADs requires inspections and, where necessary, replacement work on the specified Stewart Warner oil coolers (Schedule 1). That creates direct compliance costs (labour, parts, downtime) that are borne by the persons or organisations required to follow the ADs (owners/operators/maintainers). Time spent complying is an opportunity cost for those parties; CASA incurs administrative effort to revoke and reissue the instruments. \n\n- Incentives and behavioural effects: remaking the ADs in the same form preserves the existing technical and operational obligations set by those ADs. The immediate behavioural effect is continuity: affected parties must continue to carry out the inspection and replacement tasks required by those ADs. The revocation and reissuance do not, on their face, expand or relax those obligations (Note). \n\n- Implementation and compliance burden: enforcement and compliance remain governed by the content of the ADs as re-made. The instrument centralises the legal status of each AD as a separate instrument, which may affect how compliance is recorded or enforced administratively but does not alter the substantive requirements (preamble; Note). \n\n# Who pays and who decides\n\n- Who decides: the CASA delegate (David Alan Villiers) exercised the statutory power under subregulation 39.001(1) to revoke and re-make the listed ADs (preamble). \n- Who pays: the persons and organisations required to comply with the ADs (owners, operators, maintenance organisations responsible for aircraft fitted with the identified oil coolers) bear the costs of inspections and any replacements mandated by the ADs (Schedule 1, AD names). CASA bears the administrative cost of revocation and reissuance. \n\n# Risks and administrative notes\n\n- Because the Note states the ADs are being re-made \"in exactly the same form,\" the main risk of change is administrative/clerical (e.g. record-keeping, citation or filing differences), rather than a change to technical requirements. \n- The instrument does not itself describe any change to technical or safety requirements; it operates by changing the form and legal status of the listed ADs (preamble; Note)."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This instrument performs a pure administrative remaking function. The scope is explicitly limited to revoking and remaking two specific Airworthiness Directives in identical form. The Note confirms there is no substantive change to requirements."},"complexity_factors":["Very short instrument (under 300 words)","Only 2 defined items in Schedule 1 (the two Airworthiness Directives being remade)","No nested conditional logic or exceptions","Single clear operative clause with straightforward (a) and (b) structure","No cross-references to other legislation beyond the enabling regulation (subregulation 39.001(1))","Note explicitly states content is unchanged — no interpretive ambiguity"],"plain_english_summary":"This is a technical aviation safety instrument that **revokes and immediately remakes two existing safety rules** about aircraft oil coolers.\n\n**What it does:**\n- **Revokes** (cancels) two existing Airworthiness Directives numbered AD/COOL/1 and AD/COOL/2\n- **Remakes** them as fresh, separate legal instruments in exactly the same form as before\n\n**Who it affects:**\n- Aircraft operators and maintenance engineers who use **Stewart Warner oil coolers** in aircraft\n- The Civil Aviation Safety Authority (CASA) itself, which issues these safety mandates\n\n**Why it matters:**\nAirworthiness Directives are **legally binding safety orders** that require specific inspections, repairs, or replacements on aircraft parts. These particular directives require inspection and replacement of Stewart Warner oil coolers to prevent engine failures.\n\nThe \"revoke and remake\" process is a **housekeeping exercise** — it refreshes the legal authority of these safety rules without changing their actual content. This ensures the directives remain valid under current regulations and can be enforced properly. The oil coolers in question are critical components; if they fail, an aircraft engine could overheat and seize, potentially causing a crash.\n\n**Key takeaway:** If you own or maintain an aircraft with Stewart Warner oil coolers, you must still follow the inspection and replacement requirements — nothing has changed in what you need to do, only the legal paperwork behind the rule has been updated."}},"importantCases":[],"_links":{"self":"/api/acts/airworthiness-directives-2004-revocation-and-remaking-coolers","history":"/api/acts/airworthiness-directives-2004-revocation-and-remaking-coolers/history","analysis":"/api/acts/airworthiness-directives-2004-revocation-and-remaking-coolers/analysis","conflicts":"/api/acts/airworthiness-directives-2004-revocation-and-remaking-coolers/conflicts","importantCases":"/api/acts/airworthiness-directives-2004-revocation-and-remaking-coolers/important-cases","documents":"/api/acts/airworthiness-directives-2004-revocation-and-remaking-coolers/documents"}}