{"id":"F2009L02178","name":"AD/B737/356 - MLG Retract Actuator Beam","slug":"ad-b737-356-mlg-retract-actuator-beam","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":140336,"registerId":"commonwealth-F2009L02178-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/B737/356 | MLG Retract Actuator Beam | 7/2009 |\n| ----------- | ------------------------- | ------ |\n\n| Applicability: | Model 737-100, -200, -200C, -300, -400 and -500 series aircraft.                                                                                                                                                                                                                                                                                         |\n| -------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | Action in accordance with the technical requirements of FAA AD 2009-09-07 Amdt 39-15893.Note: Boeing Service Bulletin 737-32A1355 Revision 2, or later FAA approved revision, refers.                                                                                                                                                                    |\n| Compliance:    | As specified in the Requirement document, with a revised effective date of2 July 2009.                                                                                                                                                                                                                                                                   |\n|                | This Airworthiness Directive becomes effective on 2 July 2009.                                                                                                                                                                                                                                                                                           |\n| Background:    | The FAA received reports of broken retract actuator beams of the main landing gear and the subsequent failure of the main landing gear to fully retract. The actions required by this Directive are intended to detect and correct broken retract actuator beams, which could cause damage to the beam arm, hydraulic tubing, and flight control cables. |\n\n![](image.001.png)  \nDavid Villiers  \nDelegate of the Civil Aviation Safety Authority\n\n22 May 2009","sortOrder":0},{"sectionNumber":"AD/B737/356","sectionType":"part","heading":"AD/B737/356","content":"## AD/B737/356","sortOrder":1},{"sectionNumber":"MLG Retract Actuator Beam","sectionType":"part","heading":"MLG Retract Actuator Beam","content":"## MLG Retract Actuator Beam","sortOrder":2},{"sectionNumber":"7/2009","sectionType":"part","heading":"7/2009","content":"## 7/2009","sortOrder":3}],"analysis":{"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"},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"This directive adopts the FAA-required inspection and corrective actions for MLG retract actuator beams and applies them to the listed Boeing 737 models, with a revised effective date of 2 July 2009. It does not broaden the technical task or expand the range of affected components beyond detecting and correcting broken actuator beams as described in the source text."},"complexity_factors":["Direct incorporation by reference of an external FAA AD (2009-09-07) and Boeing Service Bulletin, requiring cross-jurisdictional document tracking","Technical, maintenance-focused actions (inspection/repair) needing trained maintenance personnel and parts","Applicability limited to a range of legacy Boeing 737 models, requiring operator-specific fleet checks","Compliance burden falls on operators (costs of inspection, repair, downtime)","Regulatory enforcement by CASA with a specific effective date (administrative scheduling and recordkeeping)","Potential operational disruption if defects are found (aircraft out of service pending repair)"],"plain_english_summary":"**What this does:** This Airworthiness Directive requires operators of Boeing 737-100/200/200C/300/400/500 series aircraft to inspect and, if needed, repair the main landing gear retract actuator beam per FAA AD 2009-09-07 and Boeing Service Bulletin 737-32A1355. It takes effect 2 July 2009.\n\n**Who it affects and why it matters:** Aircraft operators pay for inspections and repairs; the regulator (CASA) enforces compliance. The measure aims to find and fix broken beams that could damage beam arms, hydraulic lines and flight control cables."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard, narrow airworthiness directive addressing a specific mechanical defect in a defined aircraft fleet. It has not expanded beyond its original safety purpose."},"complexity_factors":["Very short document (under 300 words)","Only 1 defined term implicitly referenced (MLG = Main Landing Gear)","No nested conditional logic or exceptions","Single cross-reference to an external FAA directive and Boeing Service Bulletin","Straightforward compliance requirement: follow the referenced technical document"],"plain_english_summary":"This AD mandates inspections and corrective actions on the main landing-gear retract actuator beam of Boeing 737‑100/‑200/‑300/‑400/‑500 (“Classic”) airplanes after reports of beam fractures. It affects operators of those models and requires compliance with Boeing Service Bulletin 737‑32A1355 (Rev 2 or later). Failure could prevent gear retraction, increase drag and fuel burn, or produce debris that damages hydraulic lines or control cables, risking flight safety. Effective 2 July 2009."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b737-356-mlg-retract-actuator-beam","history":"/api/acts/ad-b737-356-mlg-retract-actuator-beam/history","analysis":"/api/acts/ad-b737-356-mlg-retract-actuator-beam/analysis","conflicts":"/api/acts/ad-b737-356-mlg-retract-actuator-beam/conflicts","importantCases":"/api/acts/ad-b737-356-mlg-retract-actuator-beam/important-cases","documents":"/api/acts/ad-b737-356-mlg-retract-actuator-beam/documents"}}