{"id":"F2006B08328","name":"AD/CESSNA 400/42 - Main Landing Gear Trunnion - Inspection and Replacement","slug":"ad-cessna-400-42-main-landing-gear-trunnion-inspection-and-replacement","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":115735,"registerId":"commonwealth-F2006B08328-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/CESSNA 400/42 - Main Landing Gear Trunnion - 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)  Cessna 400 Series Aeroplanes\n\n \n\nAD/CESSNA 400/42 Main Landing Gear Trunnion - Inspection\n\nand Replacement\n\n\n9/74\n\n \n\nApplicability: All models 402B with S/Nos. 0575 to 0632. All models 414 with S/Nos. 0503 to 0543. All models 421B with S/Nos. 0322, 0584 to 0651.\n\n \n\nDocument: Cessna SL No. ME74-14. Compliance:  As per requirement document.\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\n \n\n \n\n \n","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The extract does not show any amendment or expansion of scope beyond imposing the inspection/replacement requirement for the listed serial numbers. The AD identifies specific affected models and serial numbers (Applicability) and defers technical requirements to Cessna SL No. ME74-14 (Document/Compliance); no material change of scope from an earlier instrument is evident in the text provided."},"complexity_factors":["Reliance on an external technical document (Cessna Service Letter ME74-14) for all required inspection and replacement details (Document/Compliance).","Narrow, serial-numbered applicability requiring operators to check aircraft identity before determining applicability (Applicability).","Technical nature of the mandated work (landing gear trunnion inspection and possible replacement) requires qualified maintenance personnel and facilities.","Absence of procedural details, inspection intervals or tolerance criteria in the AD text itself — those details sit in the referenced service letter (Document/Compliance).","Regulatory enforcement is via CASA under Part 39, which creates legal obligation but leaves technical specification to the manufacturer document (Header; Document/Compliance).","Operational impacts such as parts availability, scheduling and aircraft downtime are factors external to the AD but necessary for practical compliance."],"plain_english_summary":"This AD requires owners/operators of specified Cessna 402B, 414 and 421B serial numbers to inspect—and, if indicated by Cessna Service Letter ME74‑14, replace—the main landing gear trunnion. CASA issues the directive while the Service Letter sets the technical criteria and procedures. Operators bear the costs, must schedule the work per the Service Letter, and may face downtime or parts/repair delays."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted safety directive addressing a specific mechanical defect in specific aircraft. It has not expanded beyond its original purpose of mandating inspection/replacement of main landing gear trunnions on the identified Cessna models."},"complexity_factors":["Extremely short document — only 4 substantive lines of regulatory text","No defined terms section — all language is plain technical aviation terminology","Single cross-reference to manufacturer service letter (ME74-14) for detailed compliance instructions","No conditional logic, exceptions, or nested provisions","Applicability determined by simple serial number ranges rather than complex formulae or tests"],"plain_english_summary":"**What this is:** This is an Airworthiness Directive (AD) — essentially a mandatory safety notice issued by Australia's Civil Aviation Safety Authority (CASA) for specific Cessna aircraft.\n\n**What it does:** It requires owners and operators of certain Cessna 400-series planes to inspect and potentially replace the **main landing gear trunnion** — that's the heavy-duty pivot point that attaches the main wheels to the aircraft fuselage. If this part fails, the landing gear could collapse.\n\n**Who it affects:**\n- **Cessna 402B** aircraft with serial numbers 0575 to 0632\n- **Cessna 414** aircraft with serial numbers 0503 to 0543  \n- **Cessna 421B** aircraft with serial numbers 0322, and 0584 to 0651\n\n**What must be done:** Operators must follow the instructions in **Cessna Service Letter ME74-14** — a technical document from the manufacturer detailing exactly how to inspect the trunnion and when it must be replaced.\n\n**Why it matters:** Landing gear failures are catastrophic. This AD prevents accidents by forcing specific high-risk aircraft to be checked for a known defect in a critical structural component."}},"importantCases":[],"_links":{"self":"/api/acts/ad-cessna-400-42-main-landing-gear-trunnion-inspection-and-replacement","history":"/api/acts/ad-cessna-400-42-main-landing-gear-trunnion-inspection-and-replacement/history","analysis":"/api/acts/ad-cessna-400-42-main-landing-gear-trunnion-inspection-and-replacement/analysis","conflicts":"/api/acts/ad-cessna-400-42-main-landing-gear-trunnion-inspection-and-replacement/conflicts","importantCases":"/api/acts/ad-cessna-400-42-main-landing-gear-trunnion-inspection-and-replacement/important-cases","documents":"/api/acts/ad-cessna-400-42-main-landing-gear-trunnion-inspection-and-replacement/documents"}}