{"id":"F2006B06650","name":"AD/ROCK-114/4 Amdt 1 - Lower Vertical Fin Rib - Modification","slug":"ad-rock-114-4-amdt-1-lower-vertical-fin-rib-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":48574,"registerId":"commonwealth-F2006B06650-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/ROCK-114/4 Amdt 1 - Lower Vertical Fin Rib - Modification","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)  \n\nAIRWORTHINESS DIRECTIVE\n\n![](image.001.png)\n\n![](image.001.png)  \nFor the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/ROCK-114/4 and issues the following AD under subregulation 39.1 (1) of CAR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.\n\nGulfstream (Rockwell) 114 Series Aeroplanes\n\nAD/ROCK-114/4\n\nAmdt 1\n\n  \nLower Vertical Fin Rib \\- Modification 7/2002\n\nApplicability: All models with S/Nos. 14000 to 14540.\n\nRequirement: Action in accordance with Commander Aircraft Company Service Bulletin (SB) No.\n\nSB-114-12B.\n\nNote: Aircraft modified per Gulfstream Aerospace Service Bulletins SB-114-12 or SB-114-12A are not in compliance with this Airworthiness Directive.\n\nCompliance: Unless already accomplished, within 100 hours time in service after 11 July 2002 and thereafter at intervals not exceeding 100 hours time in service until modified.\n\nThis Airworthiness Directive becomes effective on 11 July 2002.\n\nBackground: The original directive was issued to require inspection of the lower vertical fin rib during the 100 hour inspection period for cracking as required by the manufacturer’s airplane maintenance manual.\n\nAmendment 1 is issued to reflect an amendment to the manufacturers service bulletin, which increases the applicability range and an improved repair scheme when cracks are found.\n\nThe original issue of this AD became effective in May 1978.\n\n![Signature of David Alan Villiers Delegate of the Civil Aviation Safety Authority](image.002.jpeg)  \n\nDavid Alan Villiers\n\nDelegate of the Civil Aviation Safety Authority 31 May 2002\n\n![](image.001.png)\n\nThe above AD is notified in the Commonwealth of Australia Gazette on 19 June 2002.\n\n  \n\nPage 1 of 1","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":true,"description":"The amendment expands the original 1978 directive's scope by increasing the range of aircraft serial numbers covered ('increases the applicability range') and updates the repair requirements to use an improved scheme. The original was purely for inspection; this version adds a recurring inspection requirement until modification and mandates a specific updated repair protocol."},"complexity_factors":["Single, clearly defined applicability (specific aircraft serial numbers)","One primary requirement referencing an external document (Service Bulletin SB-114-12B)","Simple compliance timeline (100 hours time in service, recurring)","Minimal cross-referencing (only to Civil Aviation Regulations 1998, subregulation 39.1(1))","Short document (1 page)","Clear background explanation provided"],"plain_english_summary":"This safety order replaces a 1978 directive for Gulfstream (Rockwell) 114 series aircraft (S/N 14000–14540), requiring owners/operators to inspect the lower vertical fin rib for cracks using manufacturer Service Bulletin SB‑114‑12B. Inspections must occur within 100 flight hours after 11 July 2002 and repeat every 100 hours until a permanent modification is installed.\n\nIt affects operators of the listed serial numbers and supersedes earlier SB‑114‑12/12A modifications; cracks could threaten structural integrity, so the updated bulletin provides the mandated repair method."},"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":4,"scope_assessment":{"changed":true,"description":"Yes. Amendment 1 expands the set of affected aircraft and replaces the repair scheme — it increases applicability and updates the method for repairing cracks in the lower vertical fin rib (Background). The AD now mandates repeated inspections every 100 hours until the specified modification (Requirement/Compliance), changing the prior scope of the original 1978 AD."},"complexity_factors":["Technical maintenance requirement referencing a manufacturer service bulletin (Requirement: SB-114-12B).","Serial-number limited applicability requiring operators to determine whether each aircraft falls within S/N 14000–14540 (Applicability).","Recurring compliance timetable — inspections within 100 hours and at 100-hour intervals until modification (Compliance).","Interplay with prior modifications — aircraft modified under SB-114-12 or SB-114-12A are explicitly not in compliance (Note).","Regulatory chain: CASA delegate issues and enforces the AD under CAR 1998 subregulation 39.1(1) (preamble/signature).","Operational cost and downtime implications for operators performing inspections and modifications (Compliance/Requirement).","Amendment updates the manufacturer's repair scheme, introducing changed technical instructions to be followed (Background/Requirement)."],"plain_english_summary":"This AD requires owners/operators of Gulfstream (Rockwell) 114 aeroplanes (S/N 14000–14540) to inspect and modify the lower vertical fin rib in accordance with Commander Aircraft Company Service Bulletin SB-114-12B. Inspections must occur within 100 hours time-in-service after 11 July 2002 and repeat every 100 hours until the modification is completed. The amendment widens applicability and updates the repair method, creating a recurring inspection and modification obligation for affected operators."}},"importantCases":[],"_links":{"self":"/api/acts/ad-rock-114-4-amdt-1-lower-vertical-fin-rib-modification","history":"/api/acts/ad-rock-114-4-amdt-1-lower-vertical-fin-rib-modification/history","analysis":"/api/acts/ad-rock-114-4-amdt-1-lower-vertical-fin-rib-modification/analysis","conflicts":"/api/acts/ad-rock-114-4-amdt-1-lower-vertical-fin-rib-modification/conflicts","importantCases":"/api/acts/ad-rock-114-4-amdt-1-lower-vertical-fin-rib-modification/important-cases","documents":"/api/acts/ad-rock-114-4-amdt-1-lower-vertical-fin-rib-modification/documents"}}