{"id":"F2006B02040","name":"AD/AA-1/9 - Rudder Control - Spring Replacement","slug":"ad-aa-1-9-rudder-control-spring-replacement","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":41262,"registerId":"commonwealth-F2006B02040-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/AA-1/9 - Rudder Control - Spring Replacement","content":"---\nmeta-content-style-type: text/css\nmeta-content-type: application/xhtml+xml; charset=utf-8\nmeta-description: CASA Airworthiness Directive\nmeta-generator: Aspose.Words for .NET 22.10.0\nmeta-keywords: Issue NK,Aircraft below 5700 kg,Gulfstream (Grumman American/ American Aviation) AA-1 Series Aeroplanes,Rudder Control - Spring Replacement,9\ntitle: Airworthiness Directive - AD/AA-1/9 - Rudder Control - Spring Replacement\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 American/ American Aviation) AA-1 Series Aeroplanes\n\n \n\nAD/AA-1/9 Rudder Control - Spring Replacement NK\n\nApplicability: All models.\n\n \n\nDocument: American Aviation SB No. 131.\n\n \n\nCompliance: For aircraft with more than 1000 hours total time in service as at 25 July 1972 - within 50 hours’ time in service after 25 July 1972 and thereafter at intervals not exceeding 1000 hours’ time in service. For aircraft with less than 1000 hours total time in service - before achieving 1000 hours total time in service and thereafter at intervals not exceeding 1000 hours’ time in service.\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 a discrete, single-issue airworthiness directive focused specifically on rudder spring replacement for one aircraft series. It has not expanded beyond its original safety purpose."},"complexity_factors":["Very short document (approximately 150 words of substantive content)","Only 1 defined applicability criterion (aircraft model series)","Single compliance action (spring replacement)","Simple conditional logic based on flight hours threshold (1000 hours) and fixed date (25 July 1972)","No cross-references to other legislation beyond the enabling regulation (CAR 1998 Part 39)","No nested exceptions or sub-conditions","Single external reference (American Aviation SB No. 131) for technical procedure"],"plain_english_summary":"This AD requires owners/operators of Gulfstream AA‑1 series aeroplanes to replace the rudder control spring per American Aviation Service Bulletin No. 131.\n\nThe replacement is mandatory, with an initial and recurring 1,000‑hour interval tied to an aircraft’s flight hours as of 25 July 1972, to prevent rudder control failure; noncompliance renders the aircraft unairworthy under Australian law."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The instrument's scope applies uniformly to all AA-1 models and mandates replacement of the rudder-control spring per the referenced service bulletin with specified initial and recurring intervals. Nothing in the text indicates an expansion or contraction of scope beyond that maintenance requirement."},"complexity_factors":["Applicability covers all AA-1 models (Applicability)","Two-tier initial compliance trigger tied to total time-in-service as at a historical date (25 July 1972) (Compliance)","Recurring mandatory interval of 1,000 hours time-in-service requiring ongoing scheduling and record-keeping (Compliance)","Mandates a specific external document as the method for carrying out the work (American Aviation SB No. 131) (Document)","Issued under Civil Aviation Regulations Part 39 — mandatory legal force and regulatory enforcement (header)"],"plain_english_summary":"This directive requires replacing the rudder-control spring on all Gulfstream (Grumman American / American Aviation) AA‑1 series aeroplanes in accordance with American Aviation Service Bulletin No. 131. It makes installation and recurring replacement mandatory for owners/operators.  \n\nCompliance is time-based: aircraft with more than 1,000 hours as at 25 July 1972 must comply within 50 hours after that date and then every 1,000 hours; aircraft with less than 1,000 hours must comply before reaching 1,000 hours and then every 1,000 hours (Compliance). Owners/operators pay parts, labour and must track hours."}},"importantCases":[],"_links":{"self":"/api/acts/ad-aa-1-9-rudder-control-spring-replacement","history":"/api/acts/ad-aa-1-9-rudder-control-spring-replacement/history","analysis":"/api/acts/ad-aa-1-9-rudder-control-spring-replacement/analysis","conflicts":"/api/acts/ad-aa-1-9-rudder-control-spring-replacement/conflicts","importantCases":"/api/acts/ad-aa-1-9-rudder-control-spring-replacement/important-cases","documents":"/api/acts/ad-aa-1-9-rudder-control-spring-replacement/documents"}}