{"id":"F2006L02491","name":"AD/B737/292 - Elevator Rear Spar Web at Tab Hinge Bracket","slug":"ad-b737-292-elevator-rear-spar-web-at-tab-hinge-bracket","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":59687,"registerId":"commonwealth-F2006L02491-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Boeing 737 Series Aeroplanes","sectionType":"division","heading":"Boeing 737 Series Aeroplanes","content":"### Boeing 737 Series Aeroplanes\n\n| AD/B737/292 | Elevator Rear Spar Web at Tab Hinge Bracket | 9/2006 |\n| ----------- | ------------------------------------------- | ------ |\n\n| Applicability: | Model 737-100, -200, and -200C series aircraft; as identified in Boeing Alert Service Bulletin 737-55A1078, dated 27 October 2005, or later FAA approved revision.                                                                                                                                                                                                                                                                                                              |\n| -------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | Action in accordance with the technical requirements of FAA AD 2006-14-07Amdt 39-14678.                                                                                                                                                                                                                                                                                                                                                                                         |\n| Compliance:    | As specified in the Requirement document, with a revised effective date of31 August 2006.                                                                                                                                                                                                                                                                                                                                                                                       |\n|                | This Airworthiness Directive becomes effective on 31 August 2006.                                                                                                                                                                                                                                                                                                                                                                                                               |\n| Background:    | The FAA received reports of cracks in the elevator rear spar web at the tab hinge bracket locations. The actions required by this Directive are intended to detect and correct cracking, corrosion, interlaminar corrosion, delamination, and disbonding of the elevator rear spar, which may reduce elevator stiffness and lead to in-flight vibration. In-flight vibration may lead to elevator and horizontal stabiliser damage and reduced controllability of the aircraft. |\n\n![](image.001.png)  \nDavid Villiers  \nDelegate of the Civil Aviation Safety Authority\n\n21 July 2006","sortOrder":0},{"sectionNumber":"AD/B737/292","sectionType":"part","heading":"AD/B737/292","content":"## AD/B737/292","sortOrder":1},{"sectionNumber":"Elevator Rear Spar Web at Tab Hinge Brac","sectionType":"part","heading":"Elevator Rear Spar Web at Tab Hinge Bracket","content":"## Elevator Rear Spar Web at Tab Hinge Bracket","sortOrder":2},{"sectionNumber":"9/2006","sectionType":"part","heading":"9/2006","content":"## 9/2006","sortOrder":3}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"This AD does not expand the scope beyond its original safety purpose. It adopts existing FAA technical requirements and a Boeing service bulletin for a defined set of aircraft to detect and remedy cracking and related defects at the elevator rear spar web. The only substantive administrative change reflected in this instrument is a revised effective date (31 August 2006). Any future scope change would depend on later FAA‑approved revisions to the referenced Boeing service bulletin or additional ADs, not on this instrument itself."},"complexity_factors":["Short, single-purpose AD with one main technical requirement","Relies on external documents: FAA AD 2006-14-07Amdt 39-14678 and Boeing Alert Service Bulletin 737-55A1078","Applicability limited to specific aircraft models (737-100, -200, -200C) as identified in Boeing ASB","Administrative element: revised effective date (31 August 2006)","Technical complexity deferred to FAA AD/Boeing ASB (inspection/repair procedures not reproduced in the AD)","Compliance contingent on the content of and any later FAA‑approved revisions to the Boeing ASB"],"plain_english_summary":"**What this instrument does (mechanically)**\n\n- This Airworthiness Directive (AD) requires operators of certain Boeing 737-100, -200 and -200C aeroplanes to carry out the inspection and corrective actions specified in the identified FAA AD and Boeing Alert Service Bulletin (ASB).  In practice it adopts FAA AD 2006-14-07 (and its amendment) and Boeing Alert Service Bulletin 737-55A1078 (or later FAA‑approved revisions) as the required technical means of compliance.  The AD sets an effective date of 31 August 2006.\n\n**Who it affects**\n\n- Aircraft owners/operators of Boeing 737-100, -200 and -200C series aircraft that are listed in the Boeing Alert Service Bulletin 737-55A1078 (Applicability).  It also affects maintenance organisations and engineers who perform inspections and repairs on those aeroplanes.\n\n**Why it matters (stated purpose and mechanical effect)**\n\n- The FAA reported cracks at the elevator rear spar web where tab hinge brackets are attached.  The required inspections and repairs are intended to detect and correct cracking, corrosion, delamination, interlaminar corrosion and disbonding of the elevator rear spar.  The AD’s mechanical effect is to mandate inspection and, where necessary, repair or replacement to maintain elevator stiffness and to prevent in‑flight vibration that could damage the elevator or horizontal stabiliser and reduce controllability (Background).\n\n**How compliance works in practice**\n\n- CASA requires compliance by referring operators to the FAA AD and the Boeing ASB.  Operators must follow the inspection schedule, methods and any repair instructions set out in those documents.  If the FAA AD or Boeing ASB is updated and the update is FAA‑approved, the updated technical instructions are the means of compliance (Applicability; Requirement; Compliance).\n\n**Who pays and who decides**\n\n- Aircraft operators (owners or lessees) pay for inspections, labour and any repairs or parts.  Maintenance organisations incur the labour and regulatory-record costs.  CASA enforces the AD by making the FAA AD / Boeing ASB mandatory for Australian‑registered aircraft; the FAA AD and Boeing ASB set the technical details.\n\n**Costs, incentives and trade‑offs**\n\n- Direct costs: inspection labour, possible non‑destructive testing, spare parts and repairs, and aircraft downtime while work is done.\n- Incentive structure: operators must comply to keep the aircraft airworthy and avoid grounding or enforcement action; this creates a strong near‑term compliance incentive.  The AD concentrates compliance costs on a specific, identifiable group of operators (owners of affected 737 variants) while the safety benefit accrues to those operators, their passengers and the broader public.\n- Trade‑offs: preventive inspections and repairs reduce risk of in‑flight vibration or structural damage but impose outlays and operational disruption.  If parts or approved repair instructions are constrained, operators face longer downtime or higher costs.\n\n**Implementation and compliance risk**\n\n- The AD relies on external technical documents (FAA AD and Boeing ASB).  That creates dependency on the clarity and completeness of those documents, and on availability of FAA‑approved revisions.  Practical risks include availability of approved repair parts, access to specialised inspection techniques, and scheduling the work without excessive operational disruption.\n\n**Effect on private enterprise and markets**\n\n- Small set of operators bear the direct cost; third‑party maintenance and repair firms may see increased demand.  The AD does not change ownership, market entry, or competition rules — it imposes a compulsory safety compliance cost and a technical specification for that cost.\n\n**Summary statement**\n\n- Mechanically, this AD makes adherence to FAA AD 2006-14-07 (and the Boeing service bulletin it cites) mandatory for the listed Boeing 737 variants in Australia, with an effective date of 31 August 2006.  Its stated goal is to find and fix structural deterioration at the elevator rear spar web to prevent in‑flight vibration and attendant controllability risks (Applicability; Requirement; Compliance; Background).\n"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard Airworthiness Directive format. It precisely targets a specific structural defect in specific aircraft models. The scope remains tightly focused on elevator rear spar integrity for the 737-100/-200/-200C series, exactly as intended for aviation safety regulation."},"complexity_factors":["Extremely short document (under 300 words)","Only 1 defined applicability criterion (specific aircraft models)","Single requirement: comply with external FAA directive by reference","No conditional logic or nested exceptions within the document itself","No internal cross-references — all technical detail outsourced to Boeing Service Bulletin and FAA AD","Straightforward compliance date (single fixed date: 31 August 2006)"],"plain_english_summary":"This CASA Airworthiness Directive requires operators of older Boeing 737 (-100, -200, -200C) to inspect and repair the elevator rear spar web per the FAA/Service Bulletin instructions. Cracks, corrosion and delamination in that tail structure can cause severe vibration or loss of pitch control. Compliance is mandatory for continued legal flight in Australian airspace."},"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-b737-292-elevator-rear-spar-web-at-tab-hinge-bracket","history":"/api/acts/ad-b737-292-elevator-rear-spar-web-at-tab-hinge-bracket/history","analysis":"/api/acts/ad-b737-292-elevator-rear-spar-web-at-tab-hinge-bracket/analysis","conflicts":"/api/acts/ad-b737-292-elevator-rear-spar-web-at-tab-hinge-bracket/conflicts","importantCases":"/api/acts/ad-b737-292-elevator-rear-spar-web-at-tab-hinge-bracket/important-cases","documents":"/api/acts/ad-b737-292-elevator-rear-spar-web-at-tab-hinge-bracket/documents"}}