{"id":"F2006B03292","name":"AD/B767/110 Amdt 1 - Nacelle Strut Diagonal Brace","slug":"ad-b767-110-amdt-1-nacelle-strut-diagonal-brace","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":42729,"registerId":"commonwealth-F2006B03292-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/B767/110 Amdt 1 - Nacelle Strut Diagonal Brace","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![](image.002.png)  \nBoeing 767 Series Aeroplanes\n\nAIRWORTHINESS DIRECTIVE\n\n![](image.002.png)\n\n![](image.002.png)  \nFor the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/B767/110 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\nAD/B767/110\n\nAmdt 1\n\n  \nNacelle Strut Diagonal Brace 7/2000\n\nApplicability: Model 767 series aircraft; as listed in Boeing Alert Service Bulletin 767-54A0094, dated May 22 1998.\n\nRequirement: Action in accordance with the technical requirements of FAA AD 2000-07-05 Amdt 39-11659.\n\nNote: Replacement of the one-piece diagonal brace with the new three-piece diagonal brace, in accordance with Part 3 of the Accomplishment Instructions of Boeing Alert Service Bulletin 767-54A0094 constitutes terminating action for the requirements of this Directive.\n\nCompliance: As specified in the Requirement document for the inspection and modification requirements, with a revised effective date of 13 July 2000.\n\nThis Amendment becomes effective on 13 July 2000.\n\nBackground: The FAA received a report indicating that a fractured lug of the diagonal brace of the nacelle strut was found during a routine visual inspection of a Model 767 series aircraft. Undetected cracking of the diagonal brace of the nacelle strut could result in failure of the diagonal brace and consequent fatigue failure of a secondary load path and separation of the engine and strut.\n\nAmendment 1 is issued in response to a new FAA AD which requires accomplishment of the previously optional terminating action. This action was prompted by a report that a fractured diagonal brace lug was found during a routine maintenance inspection.\n\n![Signature of Bernard Malcolm Hole, Delegate of the Civil Aviation Safety Authority.](image.003.png)  \n\nBernard Malcolm Hole\n\nDelegate of the Civil Aviation Safety Authority 2 June 2000\n\n![](image.002.png)  \n\nThe above AD is notified in the Commonwealth of Australia Gazette on 14 June 2000.","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":true,"description":"Amendment 1 changes scope by making a previously optional terminating modification (replacement of the one-piece diagonal brace with a three-piece brace) mandatory. It revokes the prior AD and aligns Australian requirements with FAA AD 2000-07-05, imposing mandatory inspection and modification obligations on operators with compliance effective 13 July 2000."},"complexity_factors":["Cross-reference to an external FAA airworthiness directive (FAA AD 2000-07-05 Amdt 39-11659) for the substantive technical requirements (Requirement).","Dependence on a manufacturer service document for applicability and accomplishment instructions (Boeing Alert Service Bulletin 767-54A0094, dated 22 May 1998) (Applicability/Requirement).","Terminology of 'terminating action' (Note) — the one-piece to three-piece replacement ends further AD obligations, but operators must follow Part 3 of the Accomplishment Instructions to achieve it.","Legal mechanism: revocation and reissuance under subregulation 39.1(1) of CAR 1998 and delegate signature, which affects regulatory authority and enforcement.","Compliance timing tied to an externally referenced Requirement document with a specified revised effective date (13 July 2000) (Compliance), creating a hard deadline for operators.","Technical safety rationale grounded in a specific failure mode (fractured lug of diagonal brace leading to possible engine/strut separation) (Background), which drives the mandatory measures."],"plain_english_summary":"This amendment requires operators of the Boeing 767 aircraft listed in Boeing Alert Service Bulletin 767-54A0094 to inspect and, where required, modify or replace the nacelle strut diagonal brace in accordance with FAA AD 2000-07-05. It turns a previously optional replacement (one-piece to three-piece diagonal brace) into a mandatory terminating action, placing the compliance and cost obligations on aircraft operators and making CASA’s delegate-enforced AD effective 13 July 2000."},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This amendment remains tightly focused on its original purpose — addressing structural integrity of the nacelle strut diagonal brace on Boeing 767 aircraft. Amendment 1 simply updates the directive to require what was previously optional (the terminating action), in response to new FAA findings. The scope has not expanded beyond the specific airworthiness issue identified."},"complexity_factors":["Short, single-purpose directive (approximately 400 words)","Only 1 defined term implicitly referenced (the applicability via Boeing Service Bulletin)","Minimal conditional logic — essentially 'applies to these aircraft, do this action'","Heavy reliance on external documents (FAA AD 2000-07-05 and Boeing Service Bulletin 767-54A0094) for actual technical requirements","No nested exceptions or complex compliance calculations","Clear, linear structure: Applicability → Requirement → Compliance → Background"],"plain_english_summary":"This CASA safety order updates and replaces a prior directive for Boeing 767s, requiring inspections and repairs to the nacelle strut diagonal brace and mandating a permanent replacement of the one-piece brace with a new three-piece design. \n\nIt affects owners/operators of the Boeing 767s listed in Boeing Alert Service Bulletin 767-54A0094 and aligns Australian requirements with the FAA after findings that brace cracks could lead to in-flight engine separation."},"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"}},"importantCases":[],"_links":{"self":"/api/acts/ad-b767-110-amdt-1-nacelle-strut-diagonal-brace","history":"/api/acts/ad-b767-110-amdt-1-nacelle-strut-diagonal-brace/history","analysis":"/api/acts/ad-b767-110-amdt-1-nacelle-strut-diagonal-brace/analysis","conflicts":"/api/acts/ad-b767-110-amdt-1-nacelle-strut-diagonal-brace/conflicts","importantCases":"/api/acts/ad-b767-110-amdt-1-nacelle-strut-diagonal-brace/important-cases","documents":"/api/acts/ad-b767-110-amdt-1-nacelle-strut-diagonal-brace/documents"}}