{"id":"F2006L03848","name":"AD/B737/298 - Aileron Balance Tab","slug":"ad-b737-298-aileron-balance-tab","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":137732,"registerId":"commonwealth-F2006L03848-current","compilationNumber":null,"startDate":"2026-04-03","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/B737/298 | Aileron Balance Tab | 13/2006 |\n| ----------- | ------------------- | ------- |\n\n| Applicability: | All Model 737-100, -200, -200C, -300, -400, -500, -600, -700, -700C, -800, and -900 series aircraft.                                                                                                                                                                                                                                                                                                                            |\n| -------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | Action in accordance with the technical requirements of FAA AD 2006-21-01 Amdt 39-14784.Note: Boeing Special Attention Service Bulletins 737-27-1272 and 737-27-1273, or later FAA approved revisions, refer.                                                                                                                                                                                                                   |\n| Compliance:    | As specified in the Requirement document, with a revised effective date of21 December 2006.                                                                                                                                                                                                                                                                                                                                     |\n|                | This Airworthiness Directive becomes effective on 21 December 2006.                                                                                                                                                                                                                                                                                                                                                             |\n| Background:    | The FAA received reports of freeplay-induced vibration of the aileron balance tab. The potential for vibration of the control surface should be avoided because the point of transition from vibration to divergent flutter is unknown. This Directive requires repetitive measurement of the freeplay of both aileron balance tabs, and repetitive lubrication of the aileron balance tab hinge bearings and rod end bearings. |\n\n![](image.001.png)  \nDavid Villiers  \nDelegate of the Civil Aviation Safety Authority\n\n7 November 2006","sortOrder":0},{"sectionNumber":"AD/B737/298","sectionType":"part","heading":"AD/B737/298","content":"## AD/B737/298","sortOrder":1},{"sectionNumber":"Aileron Balance Tab","sectionType":"part","heading":"Aileron Balance Tab","content":"## Aileron Balance Tab","sortOrder":2},{"sectionNumber":"13/2006","sectionType":"part","heading":"13/2006","content":"## 13/2006","sortOrder":3}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The AD does not indicate any change to the listed applicability or to the FAA technical requirements it adopts. It mandates the inspections and lubrication for the specified 737 models per FAA AD 2006‑21‑01, effective 21 December 2006."},"complexity_factors":["Technical but narrow task: measurement of freeplay and lubrication are routine maintenance tasks.","Wide applicability: covers all listed 737‑100 through ‑900 series models, increasing number of affected operators.","Dependency on external documents: mandates compliance with FAA AD 2006‑21‑01 and references Boeing service bulletins.","Repetitive requirement: ongoing inspections and lubrication create recurring compliance workload and scheduling impacts.","Precision requirement: accurate freeplay measurement may require trained personnel and specific tools.","Clear regulatory command: low discretion for operators once AD adopts FAA requirements, but implementation logistics remain with operators."],"plain_english_summary":"This Airworthiness Directive requires operators of the listed Boeing 737 models to perform repetitive measurement of aileron balance‑tab freeplay and to repeatedly lubricate the tab hinge bearings and rod‑end bearings, following the technical requirements of FAA AD 2006‑21‑01 (Requirement). It takes effect 21 December 2006 (Compliance). Operators bear the inspection and maintenance cost; the regulator (CASA, via this AD) enforces the schedule and procedures to reduce the risk that freeplay‑induced vibration could progress to flutter (Background)."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard, narrow Airworthiness Directive addressing a specific technical safety issue (aileron balance tab vibration) on a specific aircraft type. It has not expanded beyond its original purpose of mandating maintenance to prevent flutter."},"complexity_factors":["Very short document (under 300 words)","Only 1 defined term implicitly used ('freeplay' — explained in context)","No cross-references to other legislation beyond a single reference to the FAA AD and Boeing service bulletins","Simple conditional structure: single requirement with compliance deadline","No nested exceptions or complex logical operators","Technical content is straightforward maintenance instruction rather than regulatory architecture"],"plain_english_summary":"This AD mandates repetitive inspections and lubrication of the aileron balance tabs on all Boeing 737 variants operating in Australia. It responds to FAA findings that loose or worn balance tabs can cause vibrations that may escalate into catastrophic flutter. Compliance is legally required before affected aircraft may fly."},"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-b737-298-aileron-balance-tab","history":"/api/acts/ad-b737-298-aileron-balance-tab/history","analysis":"/api/acts/ad-b737-298-aileron-balance-tab/analysis","conflicts":"/api/acts/ad-b737-298-aileron-balance-tab/conflicts","importantCases":"/api/acts/ad-b737-298-aileron-balance-tab/important-cases","documents":"/api/acts/ad-b737-298-aileron-balance-tab/documents"}}