{"id":"F2006B11351","name":"AD/MU-2/22 Amdt 2 - Nose Landing Gear Strut Assembly","slug":"ad-mu-2-22-amdt-2-nose-landing-gear-strut-assembly","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":57242,"registerId":"commonwealth-F2006B11351-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/MU-2/22 Amdt 2 - Nose Landing Gear Strut Assembly","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nMitsubishi MU-2 Series Aeroplanes\n\nAD/MU-2/22\n\nAmdt 2\n\n  \nNose Landing Gear Strut Assembly 10/85\n\nApplicability: All models MU-2B-10, \\-15, \\-20, \\-25 and \\-26 with S/Nos. 005 thru 347 (except S/Nos.\n\n313 and 321) and MU-2B-30, -35 and -36 with S/Nos. 501 thru 696 (except S/Nos. 652 and 661). MU-2B-25, \\-26, \\-26A and \\-40 with S/Nos. 313SA, 321SA and 348SA\n\nthru 399SA except aircraft with Trunnions identified with “SP” in the area of part number. MU-2B-35, -36A and -60 with S/Nos. 652SA, 661SA and 697SA thru 741SA except aircraft with trunnions identified with “SP” in the area of the part number.\n\nRequirement: Complete the action described in either:\n\n    Mitsubishi Heavy Industries Ltd. SB No. 181B; or\n\n    2. Mitsubishi Aircraft International Inc. SB 017/32-001, Revision A; whichever applies.\n\nNote: JCAB AD No. TCD 1768-1-85 refers.\n\nCompliance: 1. Struts with 4000 hours or more time in service \\- within 200 hours time in service after 30 November 1983;\n\n    2. Struts with less than 4000 hours \\-\n\nfor outer cylinder assembly of nose landing gear strut: within the next 200 hours;\n\nfor other parts of the nose landing gear strut: prior to achieving 4200 hours time in service;\n\n    3. Repeat the inspections at intervals not to exceed 200 hours for both (1) and (2) until affected parts are replaced by new parts identified with “SP”.\n\nBackground: A recent report highlighted the discovery of a crack in the nose landing gear strut assembly. Action is required to detect possible fatigue cracks and prevent damage or failure of the nose landing gear strut assembly. This amendment has been raised to bring the A.D. to the current JCAB TCD status, which requires inspection of the outer cylinder assembly within the next 200 hours.","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":5,"scope_assessment":{"changed":true,"description":"This amendment updates the existing AD to align with the current JCAB TCD by specifically requiring inspection of the outer cylinder assembly within the next 200 hours. The change tightens the inspection timing for that component and reiterates ongoing 200‑hour repeat inspections until parts identified with “SP” are fitted."},"complexity_factors":["Detailed applicability by model and narrow serial‑number ranges with multiple exceptions (e.g. specific S/N exclusions and ‘SP’ trunnion marking).","Multiple, differentiated compliance timelines based on accumulated hours in service (4000+ hours, <4000 hours, and 4200‑hour threshold).","Requirement to follow one of two different manufacturer service bulletins (SB No. 181B or SB 017/32‑001 Rev A).","Recurring inspection interval (every 200 hours) until replacement parts bearing ‘SP’ are installed, creating ongoing compliance burden.","Reference to an external JCAB TCD and alignment with its status, creating cross‑jurisdictional dependency.","Operational and maintenance cost implications for operators and third‑party maintenance organisations performing inspections and replacements."],"plain_english_summary":"This airworthiness directive forces owners/operators of specified Mitsubishi MU‑2 serial‑numbered aeroplanes to inspect the nose landing‑gear strut assembly and, if needed, replace affected parts using Mitsubishi Service Bulletin No. 181B or SB 017/32‑001 Rev A. Deadlines vary by part time‑in‑service (some inspections within 200 flight hours, others before 4,200 hours) and inspections must be repeated every 200 hours until parts stamped “SP” are fitted.\n\nAircraft owners/operators pay for inspections and repairs; the Civil Aviation Safety Authority issues the directive and maintenance organisations must carry out the mandated work to detect fatigue cracks and avoid strut failure."},"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"},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This is a standard amendment to an existing Airworthiness Directive. Amendment 2 updates the compliance requirements to align with current Japanese Civil Aviation Bureau (JCAB) standards, specifically adding the requirement to inspect the outer cylinder assembly within 200 hours. The scope remains focused on the original safety issue (nose landing gear strut fatigue cracking) and does not expand beyond this specific technical airworthiness concern."},"complexity_factors":["Multiple serial number ranges with specific exclusions (e.g., '005 thru 347 (except S/Nos. 313 and 321)')","Dual applicability paths depending on aircraft model and serial number suffix (SA designation)","Tiered compliance schedule based on accumulated flight hours (4,000+ hours vs. less than 4,000 hours)","Different inspection timelines for different components (outer cylinder vs. other parts)","Conditional exemption for parts marked with 'SP' identifier","Reference to external technical documents (Mitsubishi Service Bulletins SB No. 181B and SB 017/32-001 Rev A) without reproducing their content","Cross-reference to Japanese aviation authority directive (JCAB AD No. TCD 1768-1-85)"],"plain_english_summary":"This CASA Airworthiness Directive requires owners/operators of certain Mitsubishi MU-2B aircraft to inspect the nose landing gear strut assembly for fatigue cracks and to repeat inspections every 200 flight hours until upgraded \"SP\"-marked parts are fitted. It applies to specific serial-numbered aircraft (with \"SP\"‑fitted struts exempt).\n\nThe rule prevents gear collapse on landing, reducing risk of damage, injury or death, and aligns Australian requirements with the referenced Japanese safety standard."}},"importantCases":[],"_links":{"self":"/api/acts/ad-mu-2-22-amdt-2-nose-landing-gear-strut-assembly","history":"/api/acts/ad-mu-2-22-amdt-2-nose-landing-gear-strut-assembly/history","analysis":"/api/acts/ad-mu-2-22-amdt-2-nose-landing-gear-strut-assembly/analysis","conflicts":"/api/acts/ad-mu-2-22-amdt-2-nose-landing-gear-strut-assembly/conflicts","importantCases":"/api/acts/ad-mu-2-22-amdt-2-nose-landing-gear-strut-assembly/important-cases","documents":"/api/acts/ad-mu-2-22-amdt-2-nose-landing-gear-strut-assembly/documents"}}