{"id":"F2006B09022","name":"AD/DHC-1/6 - Engine Mount Pick-Up Bolt - Inspection","slug":"ad-dhc-1-6-engine-mount-pick-up-bolt-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":52700,"registerId":"commonwealth-F2006B09022-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/DHC-1/6 - Engine Mount Pick-Up Bolt - Inspection","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)  De Havilland DHC-1 (Chipmunk) Series Aeroplanes\n\n \n\nAD/DHC-1/6 Engine Mount Pick-Up Bolt - Inspection 4/54\n\nApplicability: All Canadian models.\n\n \n\nDocument: 1. DH (Canada) TNS, Series “C”, No. 39, Issue 2; or ANO 105.1.14.15.6.1 Compliance:               At intervals not exceeding 50 hours time in service.\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":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":1769},"content_quality":"ok","complexity_score":1,"scope_assessment":{"changed":false,"description":"This directive remains precisely targeted at its original purpose: ensuring the structural integrity of a single critical component (the engine mount pick-up bolt) on a specific vintage aircraft type. There is no evidence of scope expansion into broader airworthiness requirements or other aircraft models."},"complexity_factors":["Extremely brief substantive text (approximately 50 words)","No defined terms or interpretation section","Single, unambiguous applicability criterion (one aircraft type)","Simple compliance trigger (time-based interval only—50 hours)","Minimal cross-referencing (only to manufacturer technical service notes)"],"plain_english_summary":"**What this is:** A mandatory safety rule (called an Airworthiness Directive) for owners and operators of a specific vintage military trainer aircraft—the De Havilland DHC-1 Chipmunk.\n\n**What it requires:** If you operate a Canadian-built model of this aircraft, you must inspect the **engine mount pick-up bolt** (a critical fastener that secures the engine to the airframe) at least once every **50 hours of flight time**.\n\n**Why it matters:** This bolt takes enormous stress during flight. If it cracks or fails, the engine could literally fall off the aircraft. The directive forces operators to check this specific part regularly using technical guidelines from the original manufacturer (de Havilland Canada).\n\n**Who is affected:** Only owners/operators of Canadian-model DHC-1 Chipmunk aeroplanes. For the general public, this illustrates how aviation safety law works: specific mechanical components on specific aircraft types are subject to ongoing mandatory health checks."}},"importantCases":[],"_links":{"self":"/api/acts/ad-dhc-1-6-engine-mount-pick-up-bolt-inspection","history":"/api/acts/ad-dhc-1-6-engine-mount-pick-up-bolt-inspection/history","analysis":"/api/acts/ad-dhc-1-6-engine-mount-pick-up-bolt-inspection/analysis","conflicts":"/api/acts/ad-dhc-1-6-engine-mount-pick-up-bolt-inspection/conflicts","importantCases":"/api/acts/ad-dhc-1-6-engine-mount-pick-up-bolt-inspection/important-cases","documents":"/api/acts/ad-dhc-1-6-engine-mount-pick-up-bolt-inspection/documents"}}