{"id":"F2006B08333","name":"AD/CESSNA 400/47 - Main Landing Gear Fork-Bolt - Replacement","slug":"ad-cessna-400-47-main-landing-gear-fork-bolt-replacement","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":115740,"registerId":"commonwealth-F2006B08333-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/CESSNA 400/47 - Main Landing Gear Fork-Bolt - 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 400/47 Main Landing Gear Fork-Bolt - Replacement 8/76\n\nApplicability: All models with S/Nos. as listed in requirement document. Document:  1. Cessna SL ME75-23; or\n\n2. FAA AD 76-13-07.\n\n \n\nCompliance: As detailed in 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\n \n","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The AD is narrowly framed: it requires replacement of the main landing gear fork-bolt on Cessna 400 series aeroplanes identified by serial numbers listed in the requirement document. The instrument itself does not expand or narrow that scope beyond referencing the requirement document, so there is no indication in the text that the scope has been changed from the directive’s stated action."},"complexity_factors":["Cross-reference to external requirement documents (Cessna SL ME75-23 or FAA AD 76-13-07) — requires obtaining and reading other texts rather than self-contained instructions.","Applicability limited to specific serial numbers — requires checking serial numbers against a separate list.","Mandatory action is simple (part replacement) but detailed timing, method and verification are delegated to the referenced documents (Compliance), adding procedural dependency.","Regulatory provenance: issued under Part 39 and within CASA’s Schedule of Airworthiness Directives — users must understand regulatory compliance obligations even if the AD text is brief."],"plain_english_summary":"What this instrument does\n\n- This is an Airworthiness Directive (AD) titled “Main Landing Gear Fork-Bolt - Replacement” for Cessna 400 Series aeroplanes (AD/CESSNA 400/47) issued under the Civil Aviation Regulations 1998, Part 39, and published by the Civil Aviation Safety Authority (header). Mechanically, it requires the replacement of the main landing gear fork-bolt on affected aircraft.\n\nWho it affects\n\n- The directive applies to Cessna 400 series aeroplanes with the serial numbers listed in the requirement document (see “Applicability”). Operators and owners of any aircraft whose serial number appears on that list are directly affected.\n\nWhat you must consult and do\n\n- The AD tells you to follow the actions and schedule set out in the requirement document. Two documents are listed as the requirement document options: Cessna service letter SL ME75-23, or FAA AD 76-13-07 (see “Document”). The AD states: “Compliance: As detailed in requirement document.” That means the specific replacement instructions, timing, and any inspection or read-back steps are in one of those referenced documents rather than in this short AD itself.\n\nWho pays, who decides, and what changes\n\n- The Civil Aviation Safety Authority (CASA) is the issuing authority (header). The practical obligation to carry out the replacement falls on the aircraft owner/operator: they must arrange the work in accordance with the requirement document (Applicability; Document; Compliance). The AD does not include cost or funding details; therefore arrangements for parts, labour, and aircraft downtime are to be made by the owner/operator in order to comply.\n\nMechanics of compliance and implementation risk\n\n- Compliance is achieved by following the procedures and schedule contained in the referenced requirement document (Compliance). Because the AD cross-references external documents for the technical steps (Document), operators must obtain and follow the correct service letter or FAA AD. That creates a dependency on those external documents for timing, parts specification, and approved methods. Applicability is limited to specific serial numbers (Applicability), so operators must check aircraft serial numbers to determine if the AD applies.\n\nTrade-offs and incentives (source-grounded)\n\n- The AD imposes a direct obligation on a defined set of aircraft. The financial and operational costs (parts, maintenance labour, and possible aircraft downtime) are borne by the owner/operator because the AD sets a mandatory maintenance action without providing funding or exemptions in the text (Applicability; Compliance). The benefit or objective is implicit in the directive’s title (replacement of a landing gear fork-bolt) but the AD itself does not state an explicit purpose or a cost–benefit analysis.\n\nPractical notes for affected operators\n\n- Check the aircraft’s serial number against the list in the requirement document (Applicability).\n- Obtain and follow either Cessna SL ME75-23 or FAA AD 76-13-07 for the detailed instructions and schedule (Document; Compliance).\n- Plan for parts procurement, maintenance scheduling, and any record-keeping to evidence compliance.\n\nKey source citations\n\n- Issuing authority and instrument context: COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES (header).\n- Applicability: “All models with S/Nos. as listed in requirement document.” (Applicability).\n- Requirement documents listed: “Cessna SL ME75-23; or FAA AD 76-13-07.” (Document).\n- Compliance instruction: “As detailed in requirement document.” (Compliance)."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, single-issue safety directive focused specifically on one mechanical component (the main landing gear fork-bolt) for one aircraft series. It has not expanded beyond its original narrow technical purpose."},"complexity_factors":["Extremely short document (under 200 words)","No defined terms section — relies entirely on external referenced documents","Simple conditional structure: applicability → compliance requirement","No nested exceptions or conditional logic","Cross-references to only two external documents (Cessna Service Letter and FAA AD)","No penalty provisions, appeal mechanisms, or procedural subsections"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — essentially a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA).\n\n**What it does:**\nIt requires owners and operators of certain **Cessna 400 series aeroplanes** to replace the **main landing gear fork-bolt** — a critical component that helps hold the landing gear together.\n\n**Who it affects:**\nAnyone who owns or operates a Cessna 400 series aircraft with specific serial numbers listed in the referenced documents (Cessna Service Letter ME75-23 or FAA AD 76-13-07).\n\n**Why it matters:**\nLanding gear failures can be catastrophic. This directive was issued because the original fork-bolt was found to be unsafe — likely prone to cracking, corrosion, or structural failure. The replacement is mandatory, not optional, and must be done according to the timeline and procedures in the referenced documents.\n\n**Key point:** This isn't a suggestion — it's a legal requirement. Flying without complying could make your aircraft unairworthy and expose you to serious liability."}},"importantCases":[],"_links":{"self":"/api/acts/ad-cessna-400-47-main-landing-gear-fork-bolt-replacement","history":"/api/acts/ad-cessna-400-47-main-landing-gear-fork-bolt-replacement/history","analysis":"/api/acts/ad-cessna-400-47-main-landing-gear-fork-bolt-replacement/analysis","conflicts":"/api/acts/ad-cessna-400-47-main-landing-gear-fork-bolt-replacement/conflicts","importantCases":"/api/acts/ad-cessna-400-47-main-landing-gear-fork-bolt-replacement/important-cases","documents":"/api/acts/ad-cessna-400-47-main-landing-gear-fork-bolt-replacement/documents"}}