{"id":"F2006B02762","name":"AD/B727/6 - Engine Cone Bolt Nut - Inspection and Replacement","slug":"ad-b727-6-engine-cone-bolt-nut-inspection-and-replacement","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":42104,"registerId":"commonwealth-F2006B02762-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/B727/6 - Engine Cone Bolt Nut - 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/B727/6 Engine Cone Bolt Nut - Inspection and Replacement 10/65\n\nApplicabilty: All models. Document: Boeing SB No. 71-23. 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 1965 (indicated by '10/65') addressing a specific mechanical defect. It has not expanded beyond its original narrow purpose of ensuring engine cone bolt nut integrity on Boeing 727 aircraft."},"complexity_factors":["Extremely short document — only a few sentences of operative text","No defined terms section","No cross-references to other legislation beyond the parent Civil Aviation Regulations 1998","Single, unambiguous compliance requirement ('forthwith')","No conditional logic, exceptions, or alternative compliance methods","Simple applicability statement ('All models')","Relies entirely on external technical document (Boeing SB No. 71-23) for implementation details"],"plain_english_summary":"**What this is:** An Airworthiness Directive (AD) — essentially a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) for aircraft.\n\n**What it requires:** Owners and operators of **Boeing 727 aircraft** must immediately inspect and replace the **engine cone bolt nuts** on their planes. These are critical fasteners that hold parts of the jet engine together.\n\n**Why it matters:** If these nuts fail, parts of the engine could come loose during flight — potentially causing catastrophic engine damage or even an accident. The directive uses the word \"forthwith,\" which means **do it immediately** — no grace period.\n\n**Who must comply:** Anyone operating any model of Boeing 727 in Australia.\n\n**The technical basis:** The directive references Boeing Service Bulletin No. 71-23, which contains the detailed instructions for the inspection and replacement work."},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The supplied AD text does not indicate any change in scope from an earlier instrument; it states that the directive applies to all Boeing 727 models and requires inspection and replacement per Boeing SB No. 71-23 with immediate effect (Source: \"Applicability: All models\"; \"Document: Boeing SB No. 71-23\"; \"Compliance: Forthwith\"). No contrasting earlier scope or amendment is present in the supplied text."},"complexity_factors":["Very short text that issues a single mandatory action (inspection and possible replacement) — low procedural complexity (Source: AD title).","Applies to the entire Boeing 727 model range without model-by-model differentiation — broad scope but simple applicability (Source: \"Applicability: All models\").","Relies on an external technical document (Boeing SB No. 71-23) for procedural detail, reducing legislative detail but shifting complexity to the service bulletin (Source: \"Document: Boeing SB No. 71-23\").","Immediate compliance requirement (\"Forthwith\") reduces scheduling flexibility and raises operational urgency, but does not add legal complexity in the text itself (Source: \"Compliance: Forthwith\").","The supplied AD text contains no timelines, alternative-compliance provisions, or enforcement detail, which simplifies interpretation of the AD itself but can create practical implementation ambiguity requiring external reference (Source: absence of such provisions in supplied text)."],"plain_english_summary":"This Airworthiness Directive from CASA mandates immediate inspection and, if necessary, replacement of the engine cone bolt nut on all Boeing 727 models, using Boeing Service Bulletin No. 71-23 as the technical procedure.  \n\nIt affects operators, owners and their maintenance organisations (who must schedule and pay for the work) and requires prioritising this mandatory action \"forthwith.\""}},"importantCases":[],"_links":{"self":"/api/acts/ad-b727-6-engine-cone-bolt-nut-inspection-and-replacement","history":"/api/acts/ad-b727-6-engine-cone-bolt-nut-inspection-and-replacement/history","analysis":"/api/acts/ad-b727-6-engine-cone-bolt-nut-inspection-and-replacement/analysis","conflicts":"/api/acts/ad-b727-6-engine-cone-bolt-nut-inspection-and-replacement/conflicts","importantCases":"/api/acts/ad-b727-6-engine-cone-bolt-nut-inspection-and-replacement/important-cases","documents":"/api/acts/ad-b727-6-engine-cone-bolt-nut-inspection-and-replacement/documents"}}