{"id":"F2006B09584","name":"AD/ENST 28/28 - Clutch Engagement Handle Guard","slug":"ad-enst-28-28-clutch-engagement-handle-guard","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":54289,"registerId":"commonwealth-F2006B09584-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/ENST 28/28 - Clutch Engagement Handle Guard","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)  Enstrom F-28 Series Helicopters\n\n \n\nAD/ENST 28/28 Clutch Engagement Handle Guard 8/86\n\nDM\n\n \n\nApplicability: All models prior to S/No. 745.\n\n \n\nRequirement: Action in accordance with Enstrom Service Directive Bulletin No. 0070. Compliance:               Within 50 hours time in service after 30 June 1986.\n\nBackground: The possibility exists that the clutch may be disengaged with handle stowed by pressure being applied at the handle pivot.\n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\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":2284},"content_quality":"ok","complexity_score":1,"scope_assessment":{"changed":false,"description":"This airworthiness directive maintains its original narrow scope as issued in 1986, addressing only the specific mechanical defect of clutch handle disengagement risk in early-model Enstrom F-28 helicopters. No expansion beyond the original technical safety purpose is evident."},"complexity_factors":["Single operational requirement with no subsections or conditional clauses","No defined terms requiring interpretation","Direct incorporation of external technical standard (Service Bulletin No. 0070)","Clear applicability test (serial number threshold below 745)"],"plain_english_summary":"Owners/operators of Enstrom F‑28 helicopters (serial numbers below 745) must install a protective guard on the clutch engagement handle per Enstrom Service Directive Bulletin No. 0070. \n\nThis prevents accidental clutch disengagement from pressure on the stowed handle — a failure that could cut engine-to-rotor drive and cause catastrophic loss of control. Comply within 50 flight hours after 30 June 1986."}},"importantCases":[],"_links":{"self":"/api/acts/ad-enst-28-28-clutch-engagement-handle-guard","history":"/api/acts/ad-enst-28-28-clutch-engagement-handle-guard/history","analysis":"/api/acts/ad-enst-28-28-clutch-engagement-handle-guard/analysis","conflicts":"/api/acts/ad-enst-28-28-clutch-engagement-handle-guard/conflicts","importantCases":"/api/acts/ad-enst-28-28-clutch-engagement-handle-guard/important-cases","documents":"/api/acts/ad-enst-28-28-clutch-engagement-handle-guard/documents"}}