{"id":"F2006B09567","name":"AD/ENST 28/12 - Tail Rotor Pitch Link Safety Washer - Replacement","slug":"ad-enst-28-12-tail-rotor-pitch-link-safety-washer-replacement","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":54232,"registerId":"commonwealth-F2006B09567-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/ENST 28/12 - Tail Rotor Pitch Link Safety Washer - 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)  Enstrom F-28 Series Helicopters\n\n \n\nAD/ENST 28/12 Tail Rotor Pitch Link Safety Washer - Replacement\n\n\n4/76\n\n \n\nApplicability: All model F-28A with S/Nos. 03 to 349 and model 280 with S/Nos. 1001 to 1030. Document:               Enstrom Service Note No. 0033.\n\nCompliance: Within 100 hours time in service after 31 May 1976.\n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\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":2081},"content_quality":"ok","complexity_score":1,"scope_assessment":{"changed":false,"description":"This directive remains tightly focused on its original purpose: mandating replacement of a specific mechanical component (tail rotor pitch link safety washer) on identified Enstrom helicopter models. There is no indication the scope has expanded beyond this targeted safety intervention."},"complexity_factors":["Extremely short length (under 100 words of substantive content)","No defined terms or interpretation section","Single compliance requirement with clear deadline","Narrow applicability limited to specific aircraft serial numbers","No cross-references to other legislative instruments"],"plain_english_summary":"**What this requires:**\nOwners and operators of specific Enstrom helicopters must replace the safety washer on the tail rotor pitch link.\n\n**Who it affects:**\n- Enstrom F-28A helicopters with serial numbers 03 through 349\n- Enstrom 280 helicopters with serial numbers 1001 through 1030\n\n**What you must do:**\nReplace the safety washer according to Enstrom Service Note No. 0033 within 100 hours of flight time after 31 May 1976.\n\n**Why it matters:**\nThe tail rotor controls the helicopter's direction. A failed pitch link could cause loss of directional control, potentially leading to an accident. This directive ensures a critical safety component is replaced before it fails."}},"importantCases":[],"_links":{"self":"/api/acts/ad-enst-28-12-tail-rotor-pitch-link-safety-washer-replacement","history":"/api/acts/ad-enst-28-12-tail-rotor-pitch-link-safety-washer-replacement/history","analysis":"/api/acts/ad-enst-28-12-tail-rotor-pitch-link-safety-washer-replacement/analysis","conflicts":"/api/acts/ad-enst-28-12-tail-rotor-pitch-link-safety-washer-replacement/conflicts","importantCases":"/api/acts/ad-enst-28-12-tail-rotor-pitch-link-safety-washer-replacement/important-cases","documents":"/api/acts/ad-enst-28-12-tail-rotor-pitch-link-safety-washer-replacement/documents"}}