{"id":"F2006B10611","name":"AD/HU 269/49 - Engine Cooling Impeller - Bolt Inspection","slug":"ad-hu-269-49-engine-cooling-impeller-bolt-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":116485,"registerId":"commonwealth-F2006B10611-current","compilationNumber":null,"startDate":"2026-04-03","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/HU 269/49 - Engine Cooling Impeller - Bolt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)  Schweizer (Hughes) 269 Series Helicopters\n\n \n\nAD/HU 269/49 Engine Cooling Impeller - Bolt Inspection 3/75\n\nApplicability: Model 269A with S/Nos. 0011 to 0314.\n\n \n\nModel 269A-1 with S/Nos. 0001 to 0041, Model 269B with S/Nos. 0001 and subsequent. Model 269C with S/Nos. 0004 to 0389.\n\nDocument: Hughes SIN No. N-122.\n\n \n\nCompliance: Within 100 hours time in service after 31 March 1975.\n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\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":1685},"content_quality":"ok","complexity_score":1,"scope_assessment":{"changed":false,"description":"This directive remains tightly focused on its original specific technical purpose—mandating inspection of engine cooling impeller bolts on defined helicopter models. There is no expansion beyond the original aviation safety intent."},"complexity_factors":["Extremely short instrument (approximately 80 words)","No defined terms requiring interpretation","No cross-references to other legislative provisions","Single, unconditional compliance obligation","Narrow applicability limited to specific aircraft models and serial number ranges"],"plain_english_summary":"This Airworthiness Directive (AD) mandates a **safety inspection of bolts on the engine cooling impeller** for specific Schweizer (Hughes) 269 series helicopters.\n\n**Who it affects:**\nOwners and operators of:\n- Model 269A (serial numbers 0011–0314)\n- Model 269A-1 (serial numbers 0001–0041)\n- Model 269B (serial numbers 0001 onwards)\n- Model 269C (serial numbers 0004–0389)\n\n**What must be done:**\nOperators must inspect the bolts on the engine cooling impeller according to Hughes Service Information Notice (SIN) No. N-122.\n\n**When:**\nWithin 100 hours of flight time after 31 March 1975.\n\n**Why it matters:**\nThis directive prevents potential engine failure due to loose or faulty cooling impeller bolts, ensuring the helicopter remains safe to fly. Operating without completing this inspection renders the aircraft not legally airworthy."}},"importantCases":[],"_links":{"self":"/api/acts/ad-hu-269-49-engine-cooling-impeller-bolt-inspection","history":"/api/acts/ad-hu-269-49-engine-cooling-impeller-bolt-inspection/history","analysis":"/api/acts/ad-hu-269-49-engine-cooling-impeller-bolt-inspection/analysis","conflicts":"/api/acts/ad-hu-269-49-engine-cooling-impeller-bolt-inspection/conflicts","importantCases":"/api/acts/ad-hu-269-49-engine-cooling-impeller-bolt-inspection/important-cases","documents":"/api/acts/ad-hu-269-49-engine-cooling-impeller-bolt-inspection/documents"}}