{"id":"F2005L03550","name":"AD/B737/253 - Main Landing Gear Components","slug":"ad-b737-253-main-landing-gear-components","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":39064,"registerId":"commonwealth-F2005L03550-current","compilationNumber":null,"startDate":"2026-04-01","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/B737/253 | Main Landing Gear Components | 13/2005 |\n| ----------- | ---------------------------- | ------- |\n\n| Applicability: | All Model 737-100, -200, -200C, -300, -400, and -500 series aircraft.                                                                                                                                                                                                                                                                                                       |\n| -------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | Action in accordance with the technical requirements of FAA AD 2005-20-39Amdt 39-14336.Note: Boeing Service Bulletin 737-32A1367 Revision 1, or later FAA approved revision, refers.                                                                                                                                                                                        |\n| Compliance:    | As specified in the Requirement document, with a revised effective date of22 December 2005.                                                                                                                                                                                                                                                                                 |\n|                | This Airworthiness Directive becomes effective on 22 December 2005.                                                                                                                                                                                                                                                                                                         |\n| Background:    | The FAA received numerous reports of severe corrosion on one or more of three components of the main landing gear. The actions required by this Directive are intended to prevent collapse of the main landing gear or consequent damage to other components, which could result in possible departure of the aircraft from the runway and loss of control of the aircraft. |\n\n![](image.001.png)  \nDavid Villiers  \nDelegate of the Civil Aviation Safety Authority\n\n8 November 2005","sortOrder":0},{"sectionNumber":"AD/B737/253","sectionType":"part","heading":"AD/B737/253","content":"## AD/B737/253","sortOrder":1},{"sectionNumber":"Main Landing Gear Components","sectionType":"part","heading":"Main Landing Gear Components","content":"## Main Landing Gear Components","sortOrder":2},{"sectionNumber":"13/2005","sectionType":"part","heading":"13/2005","content":"## 13/2005","sortOrder":3}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The directive adopts the FAA AD's technical requirements for the listed Boeing 737 models and does not broaden applicability beyond those models. The only administrative change recorded in the text is the revised effective date of 22 December 2005; the substantive scope remains aligned with FAA AD 2005-20-39Amdt 39-14336 and Boeing Service Bulletin 737-32A1367 Rev 1."},"complexity_factors":["Incorporation by reference to FAA AD 2005-20-39Amdt 39-14336 — dependence on an external, foreign regulatory document for technical requirements.","Reference to Boeing Service Bulletin 737-32A1367 Revision 1 (or later FAA-approved revision) — potential need to track later FAA approvals/revisions.","Technical nature of required actions (inspection, corrosion remediation) — requires specialist maintenance capability and parts.","Applicability limited to specific 737 models — operators must determine applicability for their fleet.","Fixed effective date (22 December 2005) and compliance scheduling as specified in the Requirement document — creates a defined compliance timeline and administrative enforcement by CASA.","Operational risk and safety consequence linkage (main landing gear collapse) — non-compliance has direct operational restrictions and safety implications."],"plain_english_summary":"This Airworthiness Directive requires operators of Boeing 737-100/200/200C/300/400/500 series aircraft to carry out the inspections and corrective work specified in FAA AD 2005-20-39 (as amended) to detect and repair corrosion in main landing gear components. CASA set the directive effective 22 December 2005; the compliance costs and repair work fall on aircraft operators and maintenance organisations to prevent gear collapse and possible runway departure."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard airworthiness directive with a narrow, specific safety purpose — addressing corrosion in main landing gear components on specific Boeing 737 models. It has not expanded beyond its original technical safety intent."},"complexity_factors":["Very short document (approximately 200 words of substantive content)","No defined terms section — relies entirely on external references","Single operative requirement that incorporates by reference an FAA directive and Boeing service bulletin","No conditional logic, exceptions, or nested provisions within the text itself","Simple structure: applicability, requirement, compliance date, background"],"plain_english_summary":"This CASA Airworthiness Directive makes mandatory inspections and repairs on certain older Boeing 737s (-100/200/200C/300/400/500) to address severe corrosion in three main landing-gear components. It adopts the FAA’s AD and Boeing’s service bulletin, requiring Australian operators and maintenance organisations to comply.\n\nThe aim is to prevent landing‑gear collapse during landing or taxiing, eliminating a serious runway‑excursion and loss‑of‑control risk."},"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-b737-253-main-landing-gear-components","history":"/api/acts/ad-b737-253-main-landing-gear-components/history","analysis":"/api/acts/ad-b737-253-main-landing-gear-components/analysis","conflicts":"/api/acts/ad-b737-253-main-landing-gear-components/conflicts","importantCases":"/api/acts/ad-b737-253-main-landing-gear-components/important-cases","documents":"/api/acts/ad-b737-253-main-landing-gear-components/documents"}}