{"id":"F2006B02769","name":"AD/B727/66 - Engine Cone Bolt - Inspection and Replacement","slug":"ad-b727-66-engine-cone-bolt-inspection-and-replacement","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":42111,"registerId":"commonwealth-F2006B02769-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/B727/66 - Engine Cone Bolt - 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)  Boeing 727 Series Aeroplanes\n\n \n\nAD/B727/66 Engine Cone Bolt - Inspection and Replacement 2/70\n\nApplicability: All models. Document: Boeing SB No. 71-43. Compliance: Forthwith.\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\n \n","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted safety directive from 1970 (amended to version 2/70). It addresses a specific mechanical defect and has not expanded beyond its original narrow purpose of ensuring engine cone bolt integrity on Boeing 727 aircraft."},"complexity_factors":["Extremely short — only 4 substantive lines of regulatory text","No defined terms section; relies entirely on external Boeing document (SB 71-43) for technical specifications","No conditional logic, exceptions, or nested provisions","Single compliance requirement with absolute timing ('Forthwith')","Cross-reference to one external technical document only"],"plain_english_summary":"**What this is:** An Airworthiness Directive (AD) — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA).\n\n**What it does:** Requires immediate inspection and replacement of engine cone bolts on all Boeing 727 aircraft.\n\n**Who it affects:** Anyone operating Boeing 727 aeroplanes in Australia (airlines, cargo operators, private owners).\n\n**Why it matters:** Engine cone bolts are critical fasteners. If they fail, the engine could shed parts or detach — a catastrophic safety risk. The directive references Boeing Service Bulletin 71-43, which contains the technical details of what to check and how to fix it.\n\n**Key requirement:** \"Forthwith\" means **do it immediately** — not next maintenance cycle, not next week. Before the aircraft flies again, the work must be done."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The supplied AD text does not indicate any change of scope from an earlier instrument. It states applicability as \"All models,\" references Boeing SB No. 71-43 for procedure, and requires compliance \"Forthwith.\" There is no language in the supplied text indicating amendment, narrowing, or expansion compared to a prior stated intent."},"complexity_factors":["Very brief text: the AD itself contains only applicability, a document reference, and a compliance time; minimal procedural detail increases reliance on the referenced service bulletin.","Dependency on external document (Boeing SB No. 71-43) for technical procedures: operators must obtain and follow that bulletin to implement the AD.","Ambiguous timing language: the single-word timetable \"Forthwith\" is immediate but open to operational interpretation (when exactly work must be scheduled and completed).","Wide applicability: the AD covers \"All models,\" which may affect multiple operators and a large fleet, increasing logistical complexity though not spelled out in the AD.","Omitted operational details in the AD text (cost allocation, record-keeping, enforcement, exemptions), which forces implementers to seek further guidance outside the AD."],"plain_english_summary":"This Civil Aviation Safety Authority airworthiness directive applies to all Boeing 727 models and requires immediate inspection—and replacement where necessary—of an engine cone bolt. Operators must follow the procedures in Boeing Service Bulletin No. 71‑43, with compliance required \"forthwith.\" This is an urgent airworthiness action affecting every 727 operator."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b727-66-engine-cone-bolt-inspection-and-replacement","history":"/api/acts/ad-b727-66-engine-cone-bolt-inspection-and-replacement/history","analysis":"/api/acts/ad-b727-66-engine-cone-bolt-inspection-and-replacement/analysis","conflicts":"/api/acts/ad-b727-66-engine-cone-bolt-inspection-and-replacement/conflicts","importantCases":"/api/acts/ad-b727-66-engine-cone-bolt-inspection-and-replacement/important-cases","documents":"/api/acts/ad-b727-66-engine-cone-bolt-inspection-and-replacement/documents"}}