{"id":"F2006B11357","name":"AD/MU-2/28 - Nose Landing Gear Eccentric BO - Inspection and Replacement","slug":"ad-mu-2-28-nose-landing-gear-eccentric-bo-inspection-and-replacement","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":57254,"registerId":"commonwealth-F2006B11357-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/MU-2/28 - Nose Landing Gear Eccentric BO - Inspection and Replacement","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\nCOMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n \n\n![](image.001.png)  Mitsubishi MU-2 Series Aeroplanes\n\n \n\n# AD/MU-2/28 Nose Landing Gear Eccentric BO - Inspection\n\nand Replacement Applicability: All models MU-2B-26A/-40 with S/Nos. 336SA thru 457SA. Document:               Mitsubishi Aircraft International S.B. No. SBO 38/32-002.\n\n# 12/83\n\nCompliance: Unless already accomplished within 100 hours time in service after 31 December 1983 and thereafter at intervals not exceeding 100 hours time in service until replacement in accordance with requirement document.\n\n \n\nBackground: The manufacturer has received reports of failures of the nose landing gear drag strut eccentric bolt, and this inspection is intended to preclude such failures.\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 \n","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The document itself sets a limited, specific scope: it applies to MU-2B-26A and MU-2B-40 aeroplanes with S/Ns 336SA–457SA and prescribes inspection and replacement timing. There is no indication within this text that the directive’s applicability or requirements have been broadened or narrowed from an earlier intent; the directive defines the scope and the compliance mechanism (Applicability; Compliance; Document)."},"complexity_factors":["Narrow applicability limited to specific models and serial-number range (Applicability) — lowers complexity.","Clear, short compliance interval (100 hours) with a repeating requirement until replacement — straightforward but creates ongoing operational scheduling needs (Compliance).","Dependence on an external manufacturer document (Service Bulletin SBO 38/32-002) for replacement method increases practical complexity and creates an external dependency (Document).","Historical date reference (inspection within 100 hours after 31 December 1983) requires interpretation of maintenance records for legacy compliance — minor increase in complexity (Compliance).","No detailed technical steps in the directive itself — operators must consult the service bulletin, so the directive is procedural rather than technical (Document)."],"plain_english_summary":"This directive requires owners/operators of Mitsubishi MU-2B-26A and MU-2B-40 aeroplanes (S/N 336SA–457SA) to inspect the nose-landing-gear drag-strut eccentric bolt within 100 flight hours after 31 Dec 1983 and every 100 hours thereafter until the bolt is replaced per Mitsubishi Service Bulletin SBO 38/32-002. It aims to prevent bolt failures; operators bear inspection, replacement and labor costs and must follow the manufacturer’s procedure to show compliance."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted safety directive focused on a specific mechanical defect in a limited aircraft population. It has not expanded beyond its original purpose of addressing the nose landing gear eccentric bolt failure risk."},"complexity_factors":["Very short document (approximately 200 words)","Only 2 defined applicability criteria (aircraft model and serial number range)","Single compliance requirement with clear time intervals","No cross-references to other legislation or regulations beyond the parent Civil Aviation Regulations 1998","Simple conditional logic: 'unless already accomplished' is the only exception","No nested definitions or technical legal terminology"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — essentially a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) for specific aircraft.\n\n**What it does:**\n- Requires owners and operators of certain Mitsubishi MU-2B-26A and MU-2B-40 aeroplanes (specifically those with serial numbers 336SA through 457SA) to inspect a particular part of the nose landing gear — the \"eccentric bolt\" on the drag strut.\n- The inspection must happen every 100 hours of flight time until the part is eventually replaced according to the manufacturer's instructions.\n\n**Who it affects:**\n- Owners and operators of the specified Mitsubishi MU-2 aircraft models.\n- Maintenance engineers responsible for keeping these planes airworthy.\n\n**Why it matters:**\n- The manufacturer received reports that this bolt could fail. If it breaks, the nose landing gear could collapse during landing or taxiing — a serious safety risk. This directive forces proactive inspection to catch problems before they cause accidents.\n\n**Key deadline:**\n- First inspection required within 100 flight hours after 31 December 1983, then repeated every 100 flight hours until replacement."}},"importantCases":[],"_links":{"self":"/api/acts/ad-mu-2-28-nose-landing-gear-eccentric-bo-inspection-and-replacement","history":"/api/acts/ad-mu-2-28-nose-landing-gear-eccentric-bo-inspection-and-replacement/history","analysis":"/api/acts/ad-mu-2-28-nose-landing-gear-eccentric-bo-inspection-and-replacement/analysis","conflicts":"/api/acts/ad-mu-2-28-nose-landing-gear-eccentric-bo-inspection-and-replacement/conflicts","importantCases":"/api/acts/ad-mu-2-28-nose-landing-gear-eccentric-bo-inspection-and-replacement/important-cases","documents":"/api/acts/ad-mu-2-28-nose-landing-gear-eccentric-bo-inspection-and-replacement/documents"}}