{"id":"F2006B02838","name":"AD/B737/137 Amdt 1 - LE Slat Actuator Rod End","slug":"ad-b737-137-amdt-1-le-slat-actuator-rod-end","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":42180,"registerId":"commonwealth-F2006B02838-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/B737/137 Amdt 1 - LE Slat Actuator Rod End","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Safety Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \n\nAIRWORTHINESS DIRECTIVE\n\n![](image.001.png)\n\n![](image.001.png)  \nFor the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/B737/137 and issues the following 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\nBoeing 737 Series Aeroplanes\n\nAD/B737/137\n\nAmdt 1\n\n  \nLE Slat Actuator Rod End 4/2003\n\nApplicability: Model 737-300, \\-400, and \\-500 series aircraft, line numbers 1001 through 3132. Requirement: Action in accordance with the technical requirements of FAA AD 2003-03-05 Amdt\n\n39-13029\n\nNote: Boeing Service Bulletins 737-27A1211, 737-27A1211 Revision 1, 737- 27A1211 Revision 2, and 737-27A1243 refer.\n\nCompliance: As specified in the Requirement document, with a revised effective date of 17 April 2003.\n\nThis Amendment becomes effective on 17 April 2003.\n\nBackground: The FAA received reports of fractured rods on leading edge slat actuators.\n\nInvestigation revealed the rod ends fractured as a result of fatigue cracking. Fractured leading edge slat actuator rod ends could result in uncontrolled deployment of the slat and consequent reduced controllability of the aircraft.\n\nAmendment 1 is issued in response to a new FAA AD which was prompted by\n\nreports indicating that vibro-engraving was found on new rod ends during installation. Such part markings create stress risers that reduce the fatigue life of the rod ends.\n\nThe original issue of this Airworthiness Directive became effective on 23 March 2000.\n\n![Signature of David Villiers, Delegate of the Civil Aviation Safety Authority.](image.002.jpeg)  \n\nDavid Alan Villiers\n\nDelegate of the Civil Aviation Safety Authority 28 February 2003\n\n![](image.001.png)  \n\nThe above AD is notified in the Commonwealth of Australia Gazette on 26 March 2003.\n\n  \nPage 1 of 1","sortOrder":0}],"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":"Amendment 1 does not materially broaden the AD's scope of affected aircraft or create new regulatory purposes. It updates the required technical instructions by adopting a newer FAA AD (prompted by reports of vibro-engraving on new rod ends) and revises the effective date. The underlying safety objective — prevent fatigue fractures of LE slat actuator rod ends — remains the same; the change refines the corrective measures rather than expanding scope to new fleets or unrelated issues."},"complexity_factors":["Short, single-airworthiness-issue AD (limited length)","One clear applicability group: Boeing 737-300/-400/-500, line numbers 1001–3132","Primary technical content incorporated by reference to FAA AD 2003-03-05 and multiple Boeing Service Bulletins (external dependencies increase practical complexity)","Amendment only changes compliance reference and effective date; no nested exceptions","Few internal definitions or conditional branches in the CASA text","Revocation and reissuance mechanism present but straightforward"],"plain_english_summary":"**What this airworthiness directive (AD) does**\n\n- This AD applies to Boeing 737-300, -400 and -500 aeroplanes with line numbers 1001 through 3132 (see \"Applicability\").\n- It revokes the previous AD on the same subject and replaces it with an amended requirement (see \"Requirement\").\n- The AD requires operators to carry out the inspections, replacements or other actions set out in FAA AD 2003-03-05 and the Boeing service bulletins referenced (see \"Requirement\" and \"Note\").\n- The AD becomes effective 17 April 2003 (see \"Compliance\").\n\n**Why the AD was issued (safety concern)**\n\n- Investigations found that rod ends on leading edge (LE) slat actuators have fractured because of fatigue cracking (Background).\n- Fractured slat actuator rod ends can allow a slat to deploy uncontrolled, which can reduce the aircraft's controllability (Background).\n- Amendment 1 responds to further reports that some new rod ends bore \"vibro-engraving\" marks introduced during installation; those surface marks act as stress risers and shorten fatigue life (Background / Amendment 1).\n\n**Who must act and what they must do**\n\n- Aircraft operators (owners, operators, and maintenance organisations responsible for the aeroplane) must comply. The AD makes compliance mandatory for affected aeroplanes.\n- The specific technical tasks (inspection criteria, replacement intervals, part identification and corrective measures) are those set out in the FAA AD and the Boeing Service Bulletins referenced in the AD. The CASA text adopts those external technical instructions by reference (Requirement / Note).\n- The compliance schedule is the one specified in the FAA AD, with the revised effective date noted (Compliance).\n\n**Who pays and who decides**\n\n- Operators pay for inspections, labour, parts and any aircraft downtime needed to perform the required actions. If parts must be replaced, procurement and fitting costs fall on the operator unless covered by a manufacturer warranty or commercial arrangement.\n- The Civil Aviation Safety Authority (CASA) delegate issued the AD under the regulator's power (subregulation 39.1(1) of the CAR 1998). The AD relies on, and directs compliance with, a United States FAA AD and Boeing service bulletins for the technical detail.\n\n**Practical effects, compliance burden and implementation risks**\n\n- Compliance requires maintenance action following an external document (FAA AD/Boeing service bulletins). That creates administrative steps: locating the correct revisions, updating maintenance planning, and recording compliance.\n- Direct costs: labour, parts, and aircraft out-of-service time while work is done.\n- Supply/implementation risk: if compliant replacement rod ends are in limited supply, operators may face delays or temporary grounding until parts arrive.\n- Quality-control incentive: manufacturers and parts suppliers must avoid vibro-engraving or similar marking practices that create stress concentrations, or risk parts being non-compliant or early-failing.\n- The AD does not change aircraft design or operator procedures except to require adherence to the specified inspections/repairs; it does not create new certification pathways or alter operating rules beyond the mandated corrective actions.\n\n**Mechanics and legal form**\n\n- The AD revokes the earlier AD and reissues it as an amendment. It adopts by reference the FAA AD 2003-03-05 and specific Boeing Service Bulletins for the technical requirements. The CASA delegate set an effective date for the amendment (17 April 2003).\n\n**Trade-offs and opportunity costs to note**\n\n- The measure trades operator cost and downtime now for reduced risk of an in-flight slat actuator rod-end failure later. The immediate cost is concentrated on operators of the affected fleet; the safety benefit is distributed (passengers, crew, public).\n- Because the AD points to FAA and Boeing documents for technical direction, CASA relies on foreign authority and manufacturer-prescribed methods; this reduces CASA's need to draft technical detail but requires operators to track and apply external material.\n\n(References in the AD: sections headed \"Applicability\", \"Requirement\", \"Compliance\", \"Background\" and the Amendment 1 text.)"},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This amendment maintains the original scope of the 2000 directive. It updates the technical requirements to address a newly identified manufacturing defect (vibro-engraving on replacement parts) but does not expand beyond the original purpose of preventing slat actuator rod end failures on the specified Boeing 737 series aircraft."},"complexity_factors":["Short, single-page document with straightforward structure","Only 4 defined/referenced documents (FAA AD 2003-03-05 and 3 Boeing Service Bulletins)","Clear applicability section limiting scope to specific aircraft line numbers (1001-3132)","Single requirement referencing external technical document rather than detailing procedures internally","No nested exceptions or conditional logic - compliance is mandatory and time-bound","Technical aviation terminology requires domain knowledge but is explained through context"],"plain_english_summary":"This safety order requires airlines operating certain Boeing 737-300/-400/-500 airframes (line numbers 1001–3132) to inspect and repair leading edge slat actuator rod ends to prevent fatigue fractures that could cause unintended slat deployment and loss of control. The amendment updates a prior directive after discovery that vibro-engraving on replacement parts creates stress risers, sharply increasing fracture risk; operators must follow FAA AD 2003-03-05 and Boeing instructions by 17 April 2003."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b737-137-amdt-1-le-slat-actuator-rod-end","history":"/api/acts/ad-b737-137-amdt-1-le-slat-actuator-rod-end/history","analysis":"/api/acts/ad-b737-137-amdt-1-le-slat-actuator-rod-end/analysis","conflicts":"/api/acts/ad-b737-137-amdt-1-le-slat-actuator-rod-end/conflicts","importantCases":"/api/acts/ad-b737-137-amdt-1-le-slat-actuator-rod-end/important-cases","documents":"/api/acts/ad-b737-137-amdt-1-le-slat-actuator-rod-end/documents"}}