{"id":"F2006B03126","name":"AD/B747/226 - Wing Rear Spar Lower Chord Splice Plate and Kick Fitting H-11 Bolts","slug":"ad-b747-226-wing-rear-spar-lower-chord-splice-plate-and-kick-fitting-h-11-bolts","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":42498,"registerId":"commonwealth-F2006B03126-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/B747/226 - Wing Rear Spar Lower Chord Splice Plate and Kick Fitting H-11 Bolts","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 747 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 issues the following Airworthiness Directive (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/B747/226 Wing Rear Spar Lower Chord Splice\n\nPlate and Kick Fitting H-11 Bolts\n\n  \n7/2000\n\nApplicability: Model 747 series aircraft, as listed in Boeing Service Bulletin 747-57A2309, Revision 1.\n\nRequirement: Action in accordance with the technical requirements of FAA AD 2000-08-14 Amdt 39-11700.\n\nNote: Accomplishment of the actions specified in paragraph (d) of the Requirement document constitutes terminating action for the repetitive inspection requirements of this Directive.\n\nCompliance: As specified in the Requirement document for the initial and repetitive inspections, and bolt replacement, with a revised effective date of 13 July 2000.\n\nThis Airworthiness Directive becomes effective on 13 July 2000.\n\nBackground: The FAA received a report of broken bolts at the wing rear spar side-of-body on the lower chord splice plate. The actions specified by this Directive are intended to prevent cracking of the bolts due to stress corrosion, which could result in reduced structural integrity of the wing-to-body joint structure.\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 31 May 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":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard airworthiness directive implementing a specific safety fix for a known mechanical defect. It has not expanded beyond its original purpose of addressing the H-11 bolt corrosion issue on Boeing 747 wing structures."},"complexity_factors":["Very short document (approximately 250 words)","Only 1 defined term implicitly referenced (the Boeing Service Bulletin)","No nested conditional logic or exceptions","Single cross-reference to external FAA technical document (AD 2000-08-14)","Straightforward compliance structure: inspect, replace, done","No interpretation section with defined terms","Clear, single-purpose safety directive with minimal procedural variation"],"plain_english_summary":"Australia’s civil aviation regulator (CASA) requires operators of certain Boeing 747 models to inspect and replace H‑11 bolts at the wing-to-fuselage rear spar joint because the FAA found stress‑corrosion can cause bolt failure and threaten wing structural integrity. Compliance follows FAA AD 2000‑08‑14 and the referenced Boeing service bulletin, with initial and repetitive inspections and bolt replacement; completing the specified replacements ends the need for further repetitive inspections (deadline: 13 July 2000)."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"This AD implements the safety actions set out in the referenced FAA AD and applicable Boeing service bulletin; it does not broaden the set of affected parts or aircraft beyond those listed in the service bulletin and the FAA requirement. The instrument simply adopts (makes mandatory) the external FAA/Boeing technical requirements for the listed 747 models and sets an Australian effective date. There is no indication in the text that the AD extends the original safety purpose or adds unrelated measures."},"complexity_factors":["Short, single-topic Airworthiness Directive (limited length)","Relies on two external technical documents (FAA AD 2000-08-14 and Boeing Service Bulletin 747-57A2309 Rev 1) — cross-reference dependency","One conditional element (paragraph (d) terminating action removes repetitive inspections)","Limited number of in-text conditions and exceptions","Clear applicability limited to specific models listed in the service bulletin"],"plain_english_summary":"**What this instrument does (mechanics)\n\n- **Who it applies to:** Owners and operators of Boeing 747 series aircraft listed in Boeing Service Bulletin 747-57A2309, Revision 1. (See \"Applicability\".)\n\n- **What is required:** It directs those operators to carry out the inspections and bolt replacement actions set out in FAA Airworthiness Directive 2000-08-14 (Amendment 39-11700) and the referenced Boeing service bulletin. The AD makes those external technical instructions mandatory in Australia. (See \"Requirement\".)\n\n- **Timing and compliance:** Operators must follow the initial and repetitive inspection intervals and the bolt replacement timing given in the FAA AD and service bulletin. The AD became effective 13 July 2000 and adopts the compliance schedule in the Requirement document. (See \"Compliance\".)\n\n- **When the inspections stop:** Completing the specific bolt replacement described in paragraph (d) of the Requirement document ends the need for the repetitive inspections (this is a \"terminating action\"). (See \"Note\".)\n\n- **Reason given:** The Directive responds to reports of broken bolts at the wing rear spar lower chord splice plate. The stated safety concern is that stress-corrosion cracking of those bolts could reduce the structural integrity of the wing-to-body joint. (See \"Background\".)\n\nWhy this matters and who is affected\n\n- **Directly affected:** Airline operators, aircraft lessors, maintenance organisations, and licensed aircraft engineers responsible for Boeing 747s listed in the service bulletin. They must budget for and schedule inspections and eventual bolt replacement; they must amend maintenance programs and keep records of compliance.\n\n- **Who pays:** The aircraft operators (or their maintenance providers under contract) bear the cost of inspections, parts and labour, and any downtime while work is performed. There may be indirect costs for grounded aircraft or schedule disruption.\n\n- **Who decides in practice:** CASA issued the mandatory AD, but operators decide the operational timing within the prescribed compliance window and select approved maintenance providers and parts (subject to the instructions and any FAA/Boeing-approved alternatives).\n\nOfficial rationale and a practical check against costs and incentives\n\n- **Official purpose (stated):** Prevent stress-corrosion cracking of H-11 bolts at the wing rear spar lower chord splice plate and kick fitting so as to avoid loss of wing-to-body structural integrity. (Background & Requirement.)\n\n- **Practical costs and trade-offs:** The measure imposes recurring inspection costs until the terminating bolt replacement is done. Replacement requires parts and labour and removes aircraft from service for the work; operators must weigh the direct maintenance cost and lost flying revenue against the safety risk addressed by the AD. The AD also creates assured demand for the specified parts and any authorised repair facilities because operators must follow the FAA/Boeing instructions or an approved alternative.\n\n- **Implementation risks and compliance burden:** The AD depends on operators correctly identifying affected serials (per the Boeing service bulletin) and following the external FAA/Boeing technical instructions. Misinterpretation of the external documents, delays in obtaining parts, or constrained maintenance capacity can prolong compliance and increase operational disruption.\n\n- **Effect on private choice and markets:** The directive constrains operator choice to comply with the FAA AD or to obtain an approved alternative action; it can raise maintenance spending and shift demand toward OEM-approved parts and contractors. Operators might respond by accelerating replacement, changing fleet deployment, or (in long-term cost calculations) retiring older frames earlier than otherwise planned.\n\nReferences to the instrument text: Applicability (which aircraft are covered); Requirement (mandates FAA AD actions); Note (specifies terminating action); Compliance (timing and effective date); Background (safety rationale)."},"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-b747-226-wing-rear-spar-lower-chord-splice-plate-and-kick-fitting-h-11-bolts","history":"/api/acts/ad-b747-226-wing-rear-spar-lower-chord-splice-plate-and-kick-fitting-h-11-bolts/history","analysis":"/api/acts/ad-b747-226-wing-rear-spar-lower-chord-splice-plate-and-kick-fitting-h-11-bolts/analysis","conflicts":"/api/acts/ad-b747-226-wing-rear-spar-lower-chord-splice-plate-and-kick-fitting-h-11-bolts/conflicts","importantCases":"/api/acts/ad-b747-226-wing-rear-spar-lower-chord-splice-plate-and-kick-fitting-h-11-bolts/important-cases","documents":"/api/acts/ad-b747-226-wing-rear-spar-lower-chord-splice-plate-and-kick-fitting-h-11-bolts/documents"}}