{"id":"F2010L01296","name":"AD/GA8/5 Amdt 4 - Horizontal Stabiliser Inspection","slug":"ad-ga8-5-amdt-4-horizontal-stabiliser-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":83675,"registerId":"commonwealth-F2010L01296-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Gippsland Aeronautics GA8 Series Aeropla","sectionType":"division","heading":"Gippsland Aeronautics GA8 Series Aeroplanes","content":"### Gippsland Aeronautics GA8 Series Aeroplanes\n\n| AD/GA8/5 Amdt 4 | Horizontal Stabiliser Inspection | 10/2010 |\n| --------------- | -------------------------------- | ------- |\n\n| Applicability: | All GA8 aircraft serial numbers GA8-00-004 and above, and GA8-TC 320 variant, all serial numbers. |\n| -------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |\n| Requirement: | Accomplish the requirements of Gippsland Aeronautics mandatory service bulletin SB-GA8-2002-02, Issue 6, dated 21 April 2010. Accomplish the requirements (Instructions 1 to 5) in accordance with the applicability matrix in Table 1 of the service bulletin.Note: In the service bulletin, Table 1, NA = normally aspirated, TC=turbocharged. |\n| Compliance: | As per requirement document. |\n| | This Amendment becomes effective on 19 May 2010. |\n| Background: | Inspection of a high time aircraft has revealed cracks in the Horizontal Stabiliser rear spar splice plate and inboard main ribs around the area of the Horizontal Stabiliser rear pivot attachment. Additionally, failure of some attach bolts in service may be due to improper assembly.This amendment is issued to include an applicability matrix (Table 1, page 2) in the compliance section of the service bulletin for improved clarity.The previous amendment included reference to the GA8-TC 320 variant in the applicability section.Amendment 2 was issued because the requirement document now contains an inspection for cracking in horizontal stabilisers which have load transferring fittings installed.Previous amendments of this AD listed the AD requirements in full. Due to the extensive use of diagrams and photographs, it is no longer appropriate or practical to write the requirements of the service bulletin out in full in this AD. All requirements, accomplishment instructions and illustrations are contained in the service bulletin.The original issue of this AD became effective on 15 February 2007. |\n\n| | The previous amendment became effective 13 April 2010. |\n| --- | ------------------------------------------------------ |\n\n![](image.001.png)\n\nMike Higgins \nDelegate of the Civil Aviation Safety Authority\n\n11 May 2010","sortOrder":0},{"sectionNumber":"AD/GA8/5 Amdt 4","sectionType":"part","heading":"AD/GA8/5 Amdt 4","content":"## AD/GA8/5 Amdt 4","sortOrder":1},{"sectionNumber":"Horizontal Stabiliser Inspection","sectionType":"part","heading":"Horizontal Stabiliser Inspection","content":"## Horizontal Stabiliser Inspection","sortOrder":2},{"sectionNumber":"10/2010","sectionType":"part","heading":"10/2010","content":"## 10/2010","sortOrder":3}],"analysis":{"flash_summary_failed":{"failed":true,"reason":"Unauthenticated. Configure AI_GATEWAY_API_KEY or use a provider module. Learn more: https://ai-sdk.dev/unauthenticated-ai-gateway","source":"analysis-cron"},"flash_summary":{"complexity_score":5,"scope_assessment":{"changed":true,"description":"Yes. The AD’s scope has been expanded since the original issue. Amendments added an applicability matrix (Table 1) to clarify which inspections apply to which configurations, specifically included the GA8‑TC 320 variant in applicability, and Amendment 2 introduced inspections for horizontal stabilisers fitted with load‑transferring fittings. These changes broaden which aircraft and which stabiliser configurations are captured by the mandatory inspection requirements compared with the original 15 February 2007 issue."},"complexity_factors":["Relies on an external mandatory service bulletin (SB‑GA8‑2002‑02 Issue 6) for all detailed procedures and illustrations, increasing implementation complexity","Applicability uses a matrix (Table 1 in the service bulletin) that conditions which of Instructions 1–5 apply to each aircraft configuration","Multiple aircraft categories: serial number cutoff (GA8‑00‑004 and above) plus a separate variant (GA8‑TC 320 all serial numbers)","Multiple amendments history (original AD plus at least three amendments) and incremental changes to applicability and inspection scope add conditional interpretation work","Inspection targets include several structural items (rear spar splice plate, inboard main ribs, rear pivot attachment, attach bolts), which may require different inspection techniques and repair actions","Service bulletin contains extensive diagrams/photographs not reproduced in the AD, requiring cross‑referencing non‑regulatory material","Compliance timing and any follow‑up actions are governed entirely by the service bulletin rather than being stated in the AD, requiring users to interpret the bulletin’s compliance provisions"],"plain_english_summary":"**What this instrument does (mechanical change)**\n\n- It makes it mandatory for operators of affected Gippsland Aeronautics GA8 series aeroplanes to carry out the inspections and any associated actions set out in Gippsland Aeronautics Mandatory Service Bulletin SB‑GA8‑2002‑02, Issue 6, dated 21 April 2010. (See “Requirement”.)\n- The AD tells operators to follow Instructions 1–5 in that service bulletin and to use the applicability matrix at Table 1 of the bulletin to decide which inspections or actions apply to each aircraft. (See “Requirement”.)\n- The AD takes effect on 19 May 2010. (See “Compliance”.)\n\n**Which aeroplanes are affected**\n\n- All GA8 aircraft with serial numbers GA8‑00‑004 and above, and all GA8‑TC 320 variant aircraft (all serial numbers). (See “Applicability”.)\n\n**Why it matters (problem the rule addresses)**\n\n- Inspections of a high‑hours aircraft found cracks in the horizontal stabiliser rear spar splice plate and inboard main ribs near the rear pivot attachment, and some attach bolts have failed in service. The bulletin and this AD are issued to detect cracking and (where required) correct faults and assembly errors. (See “Background”.)\n\n**How it works in practice**\n\n- The AD does not restate the inspection steps and diagrams; it mandates compliance with the service bulletin, which contains the detailed inspection procedures, illustrations and the applicability matrix. Operators must perform the specified inspections and any corrective actions identified by the bulletin, according to the table that matches aircraft configuration/variant to the appropriate instructions. (See “Requirement”.)\n- If cracking, bolt failure, or incorrect assembly is found, operators will follow the corrective/repair instructions in the service bulletin (and relevant maintenance standards) to return the aircraft to an airworthy condition. (See “Background” and the service bulletin referenced in “Requirement”.)\n\n**Who pays and who decides**\n\n- Aircraft owners/operators pay for inspections, any repairs or replacements, and downtime while work is performed. Maintenance organisations or licensed engineers decide how to carry out the inspections and repairs in accordance with the mandatory service bulletin and applicable regulatory maintenance standards. The Civil Aviation Safety Authority (through its delegate) issued the AD and enforces the legal requirement to comply. (See “Applicability”, “Requirement”, “Compliance”.)\n\n**Costs, incentives and trade‑offs (practical effects and implementation risk)**\n\n- Direct costs: inspection labour, potential parts and repairs, and aircraft downtime. These are borne by owners/operators.\n- Incentives: compliance reduces the risk of in‑service failure of stabiliser fittings/bolts but increases near‑term maintenance costs; maintenance providers may receive additional work from required inspections/repairs.\n- Implementation risk: the AD relies on an external service bulletin that contains diagrams and photographs not reproduced in the AD. Incorrect interpretation of the applicability matrix or inspection criteria could result in under‑ or over‑inspection. Effective inspection depends on competent maintenance personnel and access to the bulletin’s illustrations.\n- Substitution effects: operators may choose different approved repair/overhaul options if permitted by the bulletin and regulator; they may also schedule inspections to coincide with other maintenance to reduce downtime.\n- Concentration of benefits/costs: benefits (reduced risk of structural failure) are diffuse across potential flight operations; costs (inspection/repair) are concentrated on current owners/operators of affected aircraft.\n\n**Operational note**\n\n- Because the AD mandates an external manufacturer service bulletin, compliance requires obtaining that bulletin and following its Instructions 1–5 and Table 1 applicability matrix. The AD does not list the step‑by‑step procedures in the AD text itself. (See “Requirement” and “Background”.)"},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This amendment remains tightly scoped to its original purpose of ensuring horizontal stabiliser integrity on GA8 aircraft. The amendments have refined applicability and incorporated external technical requirements by reference rather than expanding the scope to other aircraft types or systems."},"complexity_factors":["Short, single-purpose document (approximately 300 words of substantive content)","Only 1 defined term implicitly used (AD = Airworthiness Directive)","No nested legislative cross-references — refers only to external technical document (service bulletin)","Simple conditional logic: applicability determined by serial number and aircraft variant only","Contains explanatory background but requirements are delegated entirely to external technical document","No exceptions or exemptions stated within the instrument itself"],"plain_english_summary":"Owners and operators of Gippsland Aeronautics GA8 aircraft (serial GA8‑00‑004 onward and all GA8‑TC 320 turbocharged variants) must follow Service Bulletin SB‑GA8‑2002‑02 Issue 6 to inspect the horizontal stabiliser for cracks in the rear spar splice plate and inboard main ribs and for improperly installed bolts. The AD is mandatory because such defects can cause catastrophic stabiliser failure; this fourth amendment clarifies which inspections apply to which variants."}},"importantCases":[],"_links":{"self":"/api/acts/ad-ga8-5-amdt-4-horizontal-stabiliser-inspection","history":"/api/acts/ad-ga8-5-amdt-4-horizontal-stabiliser-inspection/history","analysis":"/api/acts/ad-ga8-5-amdt-4-horizontal-stabiliser-inspection/analysis","conflicts":"/api/acts/ad-ga8-5-amdt-4-horizontal-stabiliser-inspection/conflicts","importantCases":"/api/acts/ad-ga8-5-amdt-4-horizontal-stabiliser-inspection/important-cases","documents":"/api/acts/ad-ga8-5-amdt-4-horizontal-stabiliser-inspection/documents"}}