{"id":"F2006B10109","name":"AD/G164/4 Amdt 1 - Propeller Security - Inspection","slug":"ad-g164-4-amdt-1-propeller-security-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":55626,"registerId":"commonwealth-F2006B10109-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/G164/4 Amdt 1 - Propeller Security - Inspection","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/G164/4\n\nAmdt 1\n\n\nPropeller Security - Inspection 3/66\n\n \n\nApplicability: All models fitted with J5404 propeller. Document: 1. Grumman G164 SB No. 32A; or\n\n2. FAA AD 66-1-2.\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 supplied text contains no information indicating a change of scope from any prior instrument. The AD as presented applies to all models fitted with the J5404 propeller and requires immediate inspection, and it refers to two external documents for technical procedure (Applicability; Document; Compliance). No amendment details or scope‑expansion language are included in the provided extract."},"complexity_factors":["Short, narrowly targeted instrument with a single immediate action (inspection).","Clear applicability clause: limited to aircraft fitted with J5404 propeller.","Procedure detail is not included in the AD but is delegated to two external documents (Grumman SB No. 32A; FAA AD 66‑1‑2), adding a small lookup/compliance step.","Mandatory timing language is simple (‘Forthwith’), leaving little room for staged compliance but also little procedural complexity in the AD text itself.","No enforcement, exemption, or alternative compliance mechanisms are stated in the supplied text, reducing internal rule complexity but pushing detail to external sources and administrative practice."],"plain_english_summary":"### What this instrument does (mechanically)\n\n- This is Airworthiness Directive AD/G164/4 Amdt 1 titled “Propeller Security - Inspection.” It applies to Schweizer (Grumman) G‑164 (Ag‑Cat) series aeroplanes fitted with the J5404 propeller (see “Applicability”).\n- It requires an inspection of propeller security to be carried out immediately: the compliance instruction in the text is simply “Forthwith” (see “Compliance: Forthwith”).\n- The AD points operators to established inspection procedures by reference: Grumman G164 Service Bulletin No. 32A or FAA AD 66‑1‑2 (see “Document”). Those documents set out the inspection steps to be used.\n\n### Who this affects\n\n- Owners and operators of all models of the Schweizer (Grumman) G‑164 series that are fitted with a J5404 propeller (Applicability).  \n- Maintenance organisations and technicians who perform the inspections identified by the referenced service bulletin / FAA AD (Document).\n\n### Why it matters (as stated and implied by the instrument)\n\n- The instrument’s stated action is to require an inspection of propeller security for the specified aircraft/propeller combination (title + Applicability + Compliance). The directive does this by making inspection mandatory immediately and by pointing to two documents that contain the technical inspection procedure (Document).\n\n### Who pays, who decides, and what changes in behaviour\n\n- Who pays: the aircraft owners/operators pay for the inspection work, parts (if any), and for aircraft downtime while the inspection/repairs are done (inferred from the requirement that operators carry out inspections forthwith; see Compliance and Applicability).  \n- Who decides: the Civil Aviation Safety Authority has issued this AD; the AD sets the obligation and directs compliance by reference to the named technical documents (AD identifier, Document).  \n- Behaviour changes: owners/operators must schedule and carry out the specified inspection without delay; maintenance providers must perform the inspection according to the referenced service bulletin or FAA AD.\n\n### Practical trade‑offs, compliance burden and implementation notes\n\n- Compliance burden: the directive imposes an immediate operational and maintenance burden—time for inspection, possible follow‑on maintenance, and aircraft downtime (Compliance: Forthwith; Applicability).  \n- Administrative/technical determinacy: the AD does not itself describe inspection steps; it requires following external documents (Grumman SB No. 32A or FAA AD 66‑1‑2). That centralises technical detail in those documents and means compliance requires access to and use of those documents (Document).  \n- Effects on private enterprise: inspections create demand for maintenance services (possible short‑term business for maintenance shops) while imposing costs on aircraft operators. The AD constrains operators’ freedom to defer or omit the inspection because compliance is mandatory (Compliance).  \n- Discretion and enforcement: the AD language is prescriptive and immediate (“Forthwith”); the text supplied contains no alternative compliance path or exemption language and does not set out enforcement or penalty mechanisms in this extract.  \n- Opportunity cost and productivity: time and resources spent on inspections and any repairs are diverted from other productive uses for the operator and maintenance providers.\n\n### Where to look next\n\n- The inspection procedure and technical criteria are in the referenced documents: Grumman G164 Service Bulletin No. 32A and FAA AD 66‑1‑2 (Document). The AD requires operators to follow those documents when carrying out the inspection."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a narrow, targeted safety directive focused on a specific propeller model on a specific aircraft type. Amendment 1 appears to be a routine update to the original March 1966 directive, not an expansion of scope. The document remains tightly scoped to its original purpose: ensuring propeller attachment integrity on agricultural aircraft."},"complexity_factors":["Extremely short document — approximately 150 words","Only one defined term implicitly referenced (J5404 propeller)","No cross-references to other legislation or regulations beyond two external technical documents","Simple unconditional command structure: 'applies to X, do Y immediately'","No exceptions, exemptions, or conditional logic","Single operational requirement (inspection) with binary compliance status"],"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 a specific type of agricultural aircraft: the **Schweizer (formerly Grumman) G-164 \"Ag-Cat\"** series.\n\n**What it does:**\n- Requires an immediate inspection of the **J5404 propeller** installed on these planes.\n- The inspection must be done \"forthwith\" — meaning right away, without delay.\n\n**Who it affects:**\n- Owners and operators of Schweizer/Grumman G-164 aircraft fitted with the J5404 propeller.\n- Maintenance engineers working on these aircraft.\n\n**Why it matters:**\n- Propeller security is critical — if a propeller fails or detaches in flight, the result is catastrophic. This AD likely responds to a known defect or incident pattern discovered by the manufacturer (Grumman) or the US Federal Aviation Administration (FAA).\n- Compliance is **mandatory** — you cannot legally fly the aircraft until this inspection is done.\n\n**Key details:**\n- **Document references:** You can follow either Grumman Service Bulletin No. 32A or FAA AD 66-1-2 to complete the inspection.\n- **Compliance deadline:** Immediate (\"forthwith\").\n- **This is Amendment 1:** The directive has been updated once since its original issue (3/66 — March 1966)."}},"importantCases":[],"_links":{"self":"/api/acts/ad-g164-4-amdt-1-propeller-security-inspection","history":"/api/acts/ad-g164-4-amdt-1-propeller-security-inspection/history","analysis":"/api/acts/ad-g164-4-amdt-1-propeller-security-inspection/analysis","conflicts":"/api/acts/ad-g164-4-amdt-1-propeller-security-inspection/conflicts","importantCases":"/api/acts/ad-g164-4-amdt-1-propeller-security-inspection/important-cases","documents":"/api/acts/ad-g164-4-amdt-1-propeller-security-inspection/documents"}}