{"id":"F2006B06476","name":"AD/R44/8 - Lateral Cyclic Trim Spring Shaft","slug":"ad-r44-8-lateral-cyclic-trim-spring-shaft","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":47984,"registerId":"commonwealth-F2006B06476-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/R44/8 - Lateral Cyclic Trim Spring Shaft","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nRobinson R44 Series Helicopters\n\nAD/R44/8 Lateral Cyclic Trim Spring Shaft 4/98 TX\n\nApplicability: Model R44 helicopters, serial numbers 0002 through 0420, 0425, 0426, and 0427, with a C056-1 Rev. A through G spring assembly installed.\n\nRequirement: (a) Measure the diameter of the lateral cyclic trim spring shaft in accordance with the Compliance Procedure contained in Robinson Helicopter Company R44 Service Bulletin SB-26, dated 31 January 1998.\n\n    (b) If the shaft diameter varies more than 0.004 inch in any 0.50 inch of length, in the measurement area shown in Figure 1 of SB-26, replace the C056-1 Rev. A through G spring assembly with a C056-1 Rev. H spring assembly before further flight.\n\n    (c) Replacing the C056-1 Rev. A through G spring assembly with a C056-1 Rev. H spring assembly in accordance with above referenced service bulletin is considered terminating action for the requirements of this Directive.\n\nNote: FAA Priority Letter AD 98-04-12 refers.\n\nCompliance: Within 10 hours time in service after 13 February 1998, and thereafter at intervals not to exceed 25 hours time in service.\n\nThis airworthiness directive becomes effective on 13 February 1998.\n\nBackground: The FAA received a report of an incident in which a pilot felt binding in the cyclic control when attempting to move it to the left. A precautionary landing was made using only right-hand turns. Subsequent inspection revealed that a notch was worn in the lateral cyclic trim spring shaft, which caused the shaft and spring to move from the lower mount and interfere with the lateral control. Inspection of a second Model R44 helicopter revealed similar wear.","sortOrder":0}],"analysis":{"flash_summary_failed":{"failed":true,"reason":"A positive credit balance is required for all requests, including BYOK, so fallback providers remain available. Add credits at https://vercel.com/d?to=%2F%5Bteam%5D%2F%7E%2Fai%3Fmodal%3Dtop-up to continue.","source":"analysis-cron"},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The directive addresses the reported shaft-wear hazard for the identified R44 subset and does not expand obligations beyond inspection and required replacement; it specifies a terminating action (Rev H assembly) consistent with the stated safety objective."},"complexity_factors":["Narrow applicability to specific helicopter serial numbers and part revisions (identification required)","Precise measurement tolerance: variation >0.004 inch over 0.50 inch (technical measurement accuracy needed)","Dependence on manufacturer's Service Bulletin SB‑26 for compliance procedure (external document reference)","Short initial compliance window (within 10 flight hours) and frequent repeat interval (every 25 hours) increasing operational burden","Replacement to Rev H is terminating action (parts availability and replacement labour matter)"],"plain_english_summary":"This directive requires owners/operators of specified Robinson R44 helicopters (serial numbers 0002–0420, 0425–0427) fitted with C056‑1 Rev A–G lateral cyclic trim spring assemblies to measure the spring shaft diameter per Robinson Service Bulletin SB‑26 and, if variation exceeds 0.004 inch over any 0.50 inch, replace the assembly with Rev H before further flight (see Requirement (a)–(c)). It aims to prevent cyclic control binding from shaft wear; compliance creates inspection labour, measurement-tool needs and possible replacement costs, with replacement serving as terminating action."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This airworthiness directive maintains its original narrow scope—addressing a specific mechanical defect in a defined population of helicopters. It has not expanded beyond its original safety purpose."},"complexity_factors":["Single, specific mechanical component addressed","Clear numerical thresholds for compliance (0.004 inch variance, 0.50 inch length, 10 hours/25 hours intervals)","Limited applicability (specific serial numbers and part revisions only)","No nested exceptions or conditional logic—straightforward if-then requirement","Terminating action clearly defined (replacement with Rev. H assembly)","References external document (Robinson Service Bulletin SB-26) but incorporates specific measurement procedure by reference without requiring cross-referencing of multiple statutes"],"plain_english_summary":"Owners and operators of certain Robinson R44 helicopters (S/N 0002–0420, 0425–0427) with early lateral cyclic trim spring assemblies (A–G) must inspect the lateral cyclic trim spring shaft for dangerous uneven wear. If any 0.5\" section varies by more than 0.004\", the old spring assembly must be replaced with Rev. H before flight. Initial check within 10 flight hours after 13 Feb 1998 and every 25 hours thereafter; installing Rev. H cancels the repeat inspections."}},"importantCases":[],"_links":{"self":"/api/acts/ad-r44-8-lateral-cyclic-trim-spring-shaft","history":"/api/acts/ad-r44-8-lateral-cyclic-trim-spring-shaft/history","analysis":"/api/acts/ad-r44-8-lateral-cyclic-trim-spring-shaft/analysis","conflicts":"/api/acts/ad-r44-8-lateral-cyclic-trim-spring-shaft/conflicts","importantCases":"/api/acts/ad-r44-8-lateral-cyclic-trim-spring-shaft/important-cases","documents":"/api/acts/ad-r44-8-lateral-cyclic-trim-spring-shaft/documents"}}