{"id":"F2006B10108","name":"AD/G164/3 - Spray Pump Fan Armour Plates - Modification","slug":"ad-g164-3-spray-pump-fan-armour-plates-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":55622,"registerId":"commonwealth-F2006B10108-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/G164/3 - Spray Pump Fan Armour Plates - Modification","content":"---\nmeta-content-style-type: text/css\nmeta-content-type: application/xhtml+xml; charset=utf-8\nmeta-generator: Aspose.Words for .NET 22.10.0\n---\n\n?xml version=\"1.0\" encoding=\"utf-8\" standalone=\"no\"?>\n\nCOMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n \n\n![](image.001.png)  Schweizer (Grumman) G-164 (Ag-Cat) Series Aeroplanes\n\n \n\nAD/G164/3 Spray Pump Fan Armour Plates - Modification 12/63\n\nApplicability: All models with S/Nos. 1 to 220. Document:  1. Grumman G164 SB No. 23; or\n\n2. FAA AD 63-22-1.\n\n \n\nCompliance: Forthwith.\n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The provided text states the AD's applicability as all G‑164 models with serial numbers 1–220 and requires immediate compliance per the named documents. The directive itself contains no indication that this scope has been changed from a prior instrument; the text does not show an expansion or narrowing relative to any earlier scope."},"complexity_factors":["Narrow applicability (only G‑164 models S/N 1–220) reduces population complexity but concentrates burden.","Mandatory immediate compliance wording (\"Forthwith\") leaves little flexibility or staging.","Technical method not set out in the AD itself — the AD refers to external documents (Grumman SB No. 23 or FAA AD 63‑22‑1), requiring users to obtain and follow those documents.","No procedural detail, cost estimates, or alternative compliance paths included in the AD text.","Cross‑reference to a foreign authority (FAA AD) introduces potential cross‑jurisdictional administrative steps."],"plain_english_summary":"This AD requires immediate installation of spray pump fan armour plates on Schweizer (Grumman) G‑164 (Ag‑Cat) aircraft serial numbers 1–220, to be done per Grumman G164 Service Bulletin No. 23 or FAA AD 63‑22‑1. Owners/operators must arrange and fund the work forthwith; the AD mandates timing and compliance but relies on the referenced documents for technical detail and provides no explicit rationale, cost estimate, or grace period."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted safety directive addressing a specific mechanical defect in a specific aircraft model range. It has not expanded beyond its original purpose of mandating a safety modification to spray pump fan armour plates."},"complexity_factors":["Extremely short document (under 200 words)","Only 2 defined applicability criteria (model series and serial number range)","Single compliance requirement with immediate effect","Only 2 reference documents cited","No conditional logic, exceptions, or nested provisions","Standard AD format with minimal procedural detail"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — essentially a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA). It applies to specific agricultural aircraft called **Schweizer (formerly Grumman) G-164 'Ag-Cat' aeroplanes**.\n\n**What it requires:**\nOwners and operators of these planes (specifically those with serial numbers 1 to 220) must **modify the armour plates on their spray pump fans** immediately ('forthwith').\n\n**Why it matters:**\nThe armour plates protect the spray pump fan from damage. If these plates fail or are inadequate, the fan could break during operation — potentially causing the aircraft to lose critical spraying capability or suffer damage that could affect flight safety during agricultural operations (crop dusting, etc.).\n\n**How to comply:**\nOperators must follow one of two technical documents:\n- Grumman Service Bulletin No. 23, or  \n- FAA Airworthiness Directive 63-22-1 (the US equivalent safety order)\n\n**Who is affected:**\nAnyone operating these specific G-164 Ag-Cat aircraft in Australia — typically agricultural aviation businesses and pilots doing aerial spraying work."}},"importantCases":[],"_links":{"self":"/api/acts/ad-g164-3-spray-pump-fan-armour-plates-modification","history":"/api/acts/ad-g164-3-spray-pump-fan-armour-plates-modification/history","analysis":"/api/acts/ad-g164-3-spray-pump-fan-armour-plates-modification/analysis","conflicts":"/api/acts/ad-g164-3-spray-pump-fan-armour-plates-modification/conflicts","importantCases":"/api/acts/ad-g164-3-spray-pump-fan-armour-plates-modification/important-cases","documents":"/api/acts/ad-g164-3-spray-pump-fan-armour-plates-modification/documents"}}