{"id":"F2006B10163","name":"AD/GAF-N22/17 Amdt 1 - Horizontal Stabiliser Trim Tab System - Inspection and Modification","slug":"ad-gaf-n22-17-amdt-1-horizontal-stabiliser-trim-tab-system-inspection-and-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":55781,"registerId":"commonwealth-F2006B10163-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/GAF-N22/17 Amdt 1 - Horizontal Stabiliser Trim Tab System - Inspection and 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)  GAF N22 and N24 Series Aeroplanes\n\n \n\nAD/GAF-N22/17\n\nAmdt 1\n\n\nHorizontal Stabiliser Trim Tab System - Inspection and Modification\n\n\n1/79\n\n \n\nApplicability: All models N22 and N24 series delivered from the factory prior to 21 September 1978.\n\n \n\nDocument: GAF Alert SB No. AN22-55-4, Rev. 2.\n\n \n\nCompliance: Unless already accomplished, within 100 hours time in service after 31 January 1979.\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":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is Amendment 1 to an existing Airworthiness Directive. The scope remains tightly focused on the original safety issue — the horizontal stabiliser trim tab system on specific GAF aircraft models. There is no evidence of scope creep; it maintains the original applicability (pre-September 1978 aircraft) and simply updates the reference document or compliance requirements."},"complexity_factors":["Very short document (approximately 150 words)","Only 4 operative provisions: applicability, reference document, compliance deadline, and the subject matter","No defined terms section","No cross-references to other legislation beyond the parent Civil Aviation Regulations 1998","Simple conditional logic (unless already accomplished)","Single, clear compliance trigger (100 hours time in service after fixed date)"],"plain_english_summary":"This is an **Airworthiness Directive** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA). It requires owners and operators of specific GAF aircraft (the N22 and N24 series, which are small Australian-made aeroplanes) to inspect and modify the horizontal stabiliser trim tab system.\n\n**What it does:**\n- **Targets:** All GAF N22 and N24 model aeroplanes built before 21 September 1978\n- **Requires:** Inspection and modification of the trim tab system on the horizontal stabiliser (the small movable surface on the tail that helps control the aircraft's pitch)\n- **Deadline:** Must be completed within 100 hours of flying time after 31 January 1979, unless already done\n- **Based on:** GAF Alert Service Bulletin No. AN22-55-4, Revision 2\n\n**Why it matters:**\nTrim tab systems are critical for flight safety. This directive addresses a specific safety concern with these aircraft models, ensuring they meet airworthiness standards. Failure to comply makes the aircraft unairworthy — meaning it cannot legally fly."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The instrument's text specifies its applicability (N22/N24 aircraft delivered before 21 September 1978) and a single compliance obligation (inspection/modification per GAF Alert SB No. AN22-55-4, Rev. 2, within 100 hours after 31 January 1979). The document contains no wording indicating a change from any earlier scope or intent; it sets a targeted, time-limited requirement for that defined fleet (Applicability; Document; Compliance)."},"complexity_factors":["Narrow applicability limited to N22/N24 aircraft delivered before 21 Sep 1978 (reduces scope complexity) (Applicability).","Mandatory compliance timeframe measured in hours-in-service after a calendar date (requires operational tracking) (Compliance).","Technical procedures are not contained in the AD itself but are delegated to an external document (GAF Alert SB No. AN22-55-4, Rev. 2), requiring operators to obtain and interpret that bulletin (Document).","The AD text is short and prescriptive, leaving limited regulatory discretion but creating practical scheduling and maintenance complexity for affected operators.","Absence of detail in the AD about specific inspection/modification steps increases implementation risk and reliance on external technical material (Document)."],"plain_english_summary":"This Airworthiness Directive mandates inspection and modification of the horizontal stabiliser trim tab system on GAF N22/N24 aeroplanes delivered before 21 Sept 1978, to be done per GAF Alert SB No. AN22-55-4 Rev.2. Unless already completed, work must occur within 100 hours TIS after 31 Jan 1979. Compliance is mandatory, costs and scheduling fall to the aircraft owner/operator."}},"importantCases":[],"_links":{"self":"/api/acts/ad-gaf-n22-17-amdt-1-horizontal-stabiliser-trim-tab-system-inspection-and-modification","history":"/api/acts/ad-gaf-n22-17-amdt-1-horizontal-stabiliser-trim-tab-system-inspection-and-modification/history","analysis":"/api/acts/ad-gaf-n22-17-amdt-1-horizontal-stabiliser-trim-tab-system-inspection-and-modification/analysis","conflicts":"/api/acts/ad-gaf-n22-17-amdt-1-horizontal-stabiliser-trim-tab-system-inspection-and-modification/conflicts","importantCases":"/api/acts/ad-gaf-n22-17-amdt-1-horizontal-stabiliser-trim-tab-system-inspection-and-modification/important-cases","documents":"/api/acts/ad-gaf-n22-17-amdt-1-horizontal-stabiliser-trim-tab-system-inspection-and-modification/documents"}}