{"id":"F2006B10017","name":"AD/G1159/16 - Restricted Authority Electric Trim - Modification","slug":"ad-g1159-16-restricted-authority-electric-trim-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":55393,"registerId":"commonwealth-F2006B10017-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/G1159/16 - Restricted Authority Electric Trim - 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)  Gulfstream (Grumman) G1159 and G-IV Series Aeroplanes\n\n \n\nAD/G1159/16 Restricted Authority Electric Trim - Modification 8/75\n\nApplicability: All models.\n\n \n\nDocument:  Grumman Aircraft Service Change No. 182. Compliance: Before 30 April 1976.\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\n \n\n \n","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The text of the AD specifies its scope (applies to all Gulfstream G1159 and G‑IV series aeroplanes) and the corrective action (implement Grumman Aircraft Service Change No. 182) with a fixed deadline (Compliance: Before 30 April 1976). The document contains no internal indication that the scope has been altered from any prior or original intent; therefore there is no evidence in the supplied text that the scope has changed."},"complexity_factors":["Short, narrowly worded AD with a single mandated action (title; Document: Grumman Aircraft Service Change No. 182).","Applicability is broad (all models) which increases operational scope (Applicability: All models).","Technical details are not included in the AD and are contained in an external document (Document: Grumman Aircraft Service Change No. 182).","Fixed compliance deadline requires scheduling and resources (Compliance: Before 30 April 1976).","The subject matter (electric trim modification) is technical and will typically require certified maintenance capability."],"plain_english_summary":"This airworthiness directive (AD) requires operators of Gulfstream (Grumman) G1159 and G‑IV series aeroplanes to carry out a specific modification to the aircraft's electric trim system. Mechanically, the AD mandates implementation of the change described in Grumman Aircraft Service Change No. 182 to produce a “Restricted Authority Electric Trim” configuration (title and Document: Grumman Aircraft Service Change No. 182). The modification must be completed by 30 April 1976 (Compliance: Before 30 April 1976).\n\nWho it affects\n\n- Owners and operators of Gulfstream (Grumman) G1159 and G‑IV series aeroplanes, because the AD's applicability is stated as “All models” of those types (Applicability: All models).\n\nWhat it requires, in practice\n\n- Obtain and follow Grumman Aircraft Service Change No. 182 (Document: Grumman Aircraft Service Change No. 182).\n- Have the modification performed on each applicable aeroplane by the deadline given (Compliance: Before 30 April 1976).\n\nCosts, incentives and compliance burden (source‑grounded)\n\n- The AD creates a direct compliance obligation on the operators/owners of all applicable aeroplanes by its applicability clause (Applicability: All models). That obligation will typically require obtaining the referenced service change document and paying for labour, parts and aircraft downtime to perform the modification (Document: Grumman Aircraft Service Change No. 182; Compliance: Before 30 April 1976).\n- The technical content and detailed steps are not set out in the AD text itself; they are contained in the referenced Grumman service change (Document: Grumman Aircraft Service Change No. 182). Implementers therefore must rely on that external technical document to know exactly what work is required.\n\nDecision‑making and discretion\n\n- The AD fixes what must be done (the service change) and by when (the compliance date). The text does not delegate any discretion about whether to comply; it specifies the external document to follow (Document: Grumman Aircraft Service Change No. 182) and a deadline (Compliance: Before 30 April 1976).\n\nImplementation risk and trade‑offs\n\n- Because the AD refers to an external Grumman service change for technical details, successful compliance depends on access to that document and on availability of the technical skills and maintenance capacity to perform the modification. These are concrete constraints on operators (Document: Grumman Aircraft Service Change No. 182).\n- The AD does not include an explanatory rationale or cost estimates in the text provided; it states the required modification and the deadline only (title; Document: Grumman Aircraft Service Change No. 182; Compliance: Before 30 April 1976)."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a historical Airworthiness Directive from 1975 with a specific, narrow scope (electric trim modification on specific aircraft models). There is no indication of scope creep; it addresses exactly one safety issue with a clear technical fix and deadline."},"complexity_factors":["Extremely short document — only 4 substantive lines of regulatory text","No defined terms section","No cross-references to other legislation beyond the enabling Civil Aviation Regulations 1998","Single, unambiguous compliance requirement with clear deadline","No conditional logic, exceptions, or nested provisions","Refers to external technical document (Service Change No. 182) for implementation details, keeping the AD itself minimal"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — essentially a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) for aircraft.\n\n**What it does:**\n- Requires owners and operators of **Gulfstream G1159 and G-IV series aeroplanes** (business jets) to carry out a specific modification to the aircraft's **electric trim system**.\n- The modification is described in **Grumman Aircraft Service Change No. 182** — a technical document from the manufacturer detailing the required fix.\n\n**Who it affects:**\n- Anyone who owns, operates, or maintains these specific Gulfstream aircraft models in Australia.\n\n**Why it matters:**\n- The \"Restricted Authority Electric Trim\" likely refers to a flight control system that helps pilots adjust the aircraft's pitch. The modification addresses a safety issue with this system — possibly a risk of uncommanded or uncontrolled trim movement that could affect flight safety.\n- **Compliance deadline:** The work had to be completed **before 30 April 1976**.\n\n**In short:** This was a time-critical safety fix for a specific flight control problem on Gulfstream business jets, requiring a manufacturer-approved modification to be installed by a hard deadline."}},"importantCases":[],"_links":{"self":"/api/acts/ad-g1159-16-restricted-authority-electric-trim-modification","history":"/api/acts/ad-g1159-16-restricted-authority-electric-trim-modification/history","analysis":"/api/acts/ad-g1159-16-restricted-authority-electric-trim-modification/analysis","conflicts":"/api/acts/ad-g1159-16-restricted-authority-electric-trim-modification/conflicts","importantCases":"/api/acts/ad-g1159-16-restricted-authority-electric-trim-modification/important-cases","documents":"/api/acts/ad-g1159-16-restricted-authority-electric-trim-modification/documents"}}