{"id":"F2006B06703","name":"AD/S-76/20 - Power Plant Mounting Supports - Inspection and Modification","slug":"ad-s-76-20-power-plant-mounting-supports-inspection-and-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":114514,"registerId":"commonwealth-F2006B06703-current","compilationNumber":null,"startDate":"2026-04-03","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/S-76/20 - Power Plant Mounting Supports - Inspection and Modification","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)  Sikorsky S-76 Series Helicopters\n\n \n\nAD/S-76/20 Power Plant Mounting Supports - Inspection\n\nand Modification\n\n\n8/81\n\n \n\nApplicability: All models S-76 fitted with powerplant support components having P/Nos as listed in Sikorsky Customer Service Bulletin No. 76-71-6.\n\n \n\nDocument: Sikorsky CSB No. 76-71-6.\n\n \n\nCompliance: Within 100 hours time in service after 31 August 1981 unless already accomplished.\n\n \n\nBackground: The manufacturer has received reports of entrapped water causing corrosion in the tubes of the powerplant support assemblies.\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":3527},"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"The directive maintains its original narrow technical scope, addressing only the specific corrosion risk in powerplant mounting supports for Sikorsky S-76 aircraft. It remains a targeted aviation safety maintenance requirement without expansion into broader operational or administrative matters."},"complexity_factors":["Extremely brief text (under 150 words) with only 4 operative sections","All technical requirements incorporated by reference to an external service bulletin","Single, unambiguous applicability criterion (specific helicopter model and part numbers)","Straightforward compliance deadline with no conditional exceptions or extensions","No definitions section or complex cross-references to other legislation"],"plain_english_summary":"**What this is:** A mandatory safety directive (called an Airworthiness Directive) issued by the Civil Aviation Safety Authority for owners and operators of Sikorsky S-76 helicopters.\n\n**What it requires:** You must inspect and modify the powerplant (engine) mounting supports on affected aircraft. The manufacturer found that water can become trapped inside the support tubes, causing corrosion that could dangerously weaken the structure holding the engine in place.\n\n**Who it affects:** All S-76 helicopter models fitted with specific powerplant support components listed in Sikorsky Customer Service Bulletin No. 76-71-6.\n\n**When to do it:** Within 100 hours of flying time after 31 August 1981, unless the work has already been completed.\n\n**How to do it:** Follow the inspection and modification instructions contained in Sikorsky Customer Service Bulletin No. 76-71-6."}},"importantCases":[],"_links":{"self":"/api/acts/ad-s-76-20-power-plant-mounting-supports-inspection-and-modification","history":"/api/acts/ad-s-76-20-power-plant-mounting-supports-inspection-and-modification/history","analysis":"/api/acts/ad-s-76-20-power-plant-mounting-supports-inspection-and-modification/analysis","conflicts":"/api/acts/ad-s-76-20-power-plant-mounting-supports-inspection-and-modification/conflicts","importantCases":"/api/acts/ad-s-76-20-power-plant-mounting-supports-inspection-and-modification/important-cases","documents":"/api/acts/ad-s-76-20-power-plant-mounting-supports-inspection-and-modification/documents"}}