{"id":"F2006B02871","name":"AD/B737/168 - Main Wheel Well Junction Box Electrical Wire Chafing","slug":"ad-b737-168-main-wheel-well-junction-box-electrical-wire-chafing","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":42213,"registerId":"commonwealth-F2006B02871-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/B737/168 - Main Wheel Well Junction Box Electrical Wire Chafing","content":"---\nmeta-content-style-type: text/css\nmeta-content-type: application/xhtml+xml; charset=utf-8\nmeta-generator: Aspose.Words for .NET 22.10.0\n---\n\n?xml version=\"1.0\" encoding=\"utf-8\" standalone=\"no\"?>\n\n \n\n![](image.001.png)\n\n# AIRWORTHINESS DIRECTIVE\n\nFor the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (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\n![](image.001.png)\n\n \n\nBoeing 737 Series Aeroplanes\n\n \n\n# AD/B737/168 Main Wheel Well Junction Box Electrical Wire Chafing\n\n\n12/2001\n\n \n\nApplicability: All Model 737-100, -200, -300, -400, and -500 series aeroplanes; and Model 737-600,\n\n-700, -800, and -900 series aeroplanes, line numbers 1 through 706 inclusive.\n\n \n\nRequirement: 1. Perform a detailed visual inspection of the wire bundles in the four junction boxes formed by electrical disconnect brackets on the left and right sides of the main wheel wells to detect damage or chafing, as specified in Boeing Service Letter (SL) 737-SL-24-111-B, dated 16 January 2001.\n\n \n\nNote 1: For the purposes of this Directive, a detailed visual inspection is defined as: “An intensive visual examination of a specific structural area, system, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at intensity deemed appropriate by the inspector. Inspection aids such as mirror, magnifying lenses, etc., may be used. Surface cleaning and elaborate access procedures may be required.”\n\n \n\n2.        If chafing is not detected during the Requirement 1 inspection, protect the wire bundles from chafing against the cover plate of the junction box in accordance with SL 737-SL-24-111-B.\n\n \n\n3.        If any chafing is detected during the Requirement 1 inspection, repair the wiring and protect the wire bundles from chafing against the cover plate of the junction box in accordance with SL 737-SL-24-111-B.\n\n \n\nNote 2: Boeing SL 737-SL-24-111-B refers to Boeing Standard Wiring Practices Manual D6-54446, Subject 20-10-13, as the appropriate source of repair instructions if any damaged wiring is found.\n\n \n\nNote 3: FAA AD 2001-20-10 Amdt 39-12458 refers.\n\n \n\nCompliance: For Requirement 1 - Within 18 months after the effective date of this Directive.\n\n \n\nFor Requirement 2 - Before further flight. For Requirement 3 - Before further flight.\n\nThis Airworthiness Directive becomes effective on 29 November 2001.\n\n \n\nBoeing 737 Series Aeroplanes\n\n \n\nAD/B737/168 (Continued)\n\n \n\nBackground:  This Directive requires inspection of wire bundles in main wheel well junction boxes to detect chafing or damage, the installation of protection for the wires bundles and, if necessary, repair of any damage to the wiring. These actions are intended to prevent wire damage, which could result in arcing and consequent fire in the main wheel well or passenger cabin, or inability to stop the flow of fuel to an engine or to the auxiliary power unit in the event of a fire.\n\n![Signature of Eugene Paul Holzapfel, Delegate of the Civil Aviation Safety Authority.](image.002.png)  \n\n\n \n\nEugene Paul Holzapfel\n\nDelegate of the Civil Aviation Safety Authority 17 October 2001\n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n![](image.001.png)  \n\n\nThe above AD is notified in the Commonwealth of Australia Gazette on 7 November 2001.\n","sortOrder":0}],"analysis":{"flash_summary_failed":{"failed":true,"reason":"Unauthenticated. Configure AI_GATEWAY_API_KEY or use a provider module. Learn more: https://ai-sdk.dev/unauthenticated-ai-gateway","source":"analysis-cron"},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The text sets the applicability and mandatory actions as issued; there is no amendment or extension in this document that changes the AD's original scope. It applies to the listed 737 models (and specified line numbers) and mandates inspection, protection, and repair per the Boeing service letter."},"complexity_factors":["Cross‑references to external technical material: Boeing Service Letter 737‑SL‑24‑111‑B and Boeing Standard Wiring Practices Manual D6‑54446 (adds dependency on manufacturer documents).","Defined inspection standard (Note 1) specifying lighting, aids, cleaning and access procedures increases procedural detail.","Applicability spans multiple 737 submodels and specific line numbers (narrows scope for later series).","Clear compliance timing: inspection within 18 months; protection/repairs required before further flight (operational impact if defects found).","Repair obligation tied to service letter procedures (creates reliance on maintenance organisations following Boeing instructions).","Reference to FAA AD 2001‑20‑10 (harmonisation but requires cross‑checking).","Enforcement and legal effect delegated to CASA (delegate signed AD), so legal force is immediate for affected operators."],"plain_english_summary":"**What it does:** Requires operators of specified Boeing 737 models to perform a detailed visual inspection of wire bundles in the four main wheel‑well junction boxes, and to install protection or repair any chafing in accordance with Boeing Service Letter 737‑SL‑24‑111‑B. \n\nCASA states the purpose is to prevent wire damage that could cause arcing, fire, or loss of fuel shut‑off; operators pay for inspections and any repairs, must inspect within 18 months and complete protection/repairs before further flight."},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This AD maintains its original narrow scope — addressing a specific unsafe condition (electrical wire chafing in main wheel well junction boxes) on specific Boeing 737 aircraft models. It has not expanded beyond this original safety purpose."},"complexity_factors":["Single specific technical issue (wire chafing in defined location) with clear sequential requirements","Only 3 defined requirements with straightforward conditional logic (if/then structure)","References external technical documents (Boeing Service Letter and Standard Wiring Practices Manual) rather than reproducing complex instructions inline","Limited applicability scope (specific aircraft models and line numbers)","Simple compliance timeline (single 18-month window for inspection, immediate action for repairs)","No nested exceptions or complex cross-referencing between multiple legislative instruments"],"plain_english_summary":"This AD mandates inspection of electrical wire bundles in four junction boxes inside the main wheel wells on specified Boeing 737 models (classic and certain early NG line numbers) to detect chafing or other damage. If clear, operators must install protective measures; if damaged, repair and protect before next flight. Compliance is required within 18 months. It addresses risk of electrical arcing that could cause fire or loss of fuel shutoff capability."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b737-168-main-wheel-well-junction-box-electrical-wire-chafing","history":"/api/acts/ad-b737-168-main-wheel-well-junction-box-electrical-wire-chafing/history","analysis":"/api/acts/ad-b737-168-main-wheel-well-junction-box-electrical-wire-chafing/analysis","conflicts":"/api/acts/ad-b737-168-main-wheel-well-junction-box-electrical-wire-chafing/conflicts","importantCases":"/api/acts/ad-b737-168-main-wheel-well-junction-box-electrical-wire-chafing/important-cases","documents":"/api/acts/ad-b737-168-main-wheel-well-junction-box-electrical-wire-chafing/documents"}}