{"id":"F2006B07472","name":"AD/TPE 331/7 - Fuel Control - Modification","slug":"ad-tpe-331-7-fuel-control-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":49869,"registerId":"commonwealth-F2006B07472-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/TPE 331/7 - Fuel Control - 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 - 106 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n \n\n![](image.001.png)  AlliedSignal (Garrett/AiResearch) Turbine Engines - TPE 331 Series\n\n \n\nAD/TPE 331/7 Fuel Control - Modification 3/86\n\nApplicability: TPE-331-25A, -25D, -25F, -43 and -47 engines.\n\n \n\nDocument: AiResearch TPE-331 SB Nos. 25A, 25B, 25C and 25D as applicable; or AD/AIR-T/4.\n\nCompliance: Forthwith.\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":1859},"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, single-issue safety directive focused exclusively on fuel control modifications for specific engine models. It maintains the standard scope of an airworthiness directive—mandating a specific maintenance action to address a identified safety defect without expanding into broader regulatory matters."},"complexity_factors":["Very short text (minimal defined terms or clauses)","Delegates all technical detail to external manufacturer documents (Service Bulletins)","No exceptions, conditional provisions, or nested logic","Limited to five specific engine model variants"],"plain_english_summary":"**What this is:** A mandatory safety instruction (called an **Airworthiness Directive** or AD) issued under Australia’s Civil Aviation Regulations 1998.\n\n**What it requires:** Owners and operators must immediately modify the fuel control systems on specific AlliedSignal (Garrett/AiResearch) TPE-331 turbine engines. The affected models are:\n- TPE-331-25A\n- TPE-331-25D  \n- TPE-331-25F\n- TPE-331-43\n- TPE-331-47\n\n**How to comply:** Follow the technical instructions in the manufacturer’s Service Bulletins (Nos. 25A, 25B, 25C, or 25D—whichever matches your engine), or alternatively comply with directive AD/AIR-T/4.\n\n**When:** **Forthwith** (immediately—without waiting for the next scheduled maintenance).\n\n**Why it matters:** This directive addresses specific safety risks in the fuel control systems of these engines. Flying without completing this modification breaches aviation law and risks mechanical failure."}},"importantCases":[],"_links":{"self":"/api/acts/ad-tpe-331-7-fuel-control-modification","history":"/api/acts/ad-tpe-331-7-fuel-control-modification/history","analysis":"/api/acts/ad-tpe-331-7-fuel-control-modification/analysis","conflicts":"/api/acts/ad-tpe-331-7-fuel-control-modification/conflicts","importantCases":"/api/acts/ad-tpe-331-7-fuel-control-modification/important-cases","documents":"/api/acts/ad-tpe-331-7-fuel-control-modification/documents"}}