{"id":"F2006B02240","name":"AD/AL 250/19 - Fuel System - Power Turbine Governor to Control Fuel Tube Clamp - Installation","slug":"ad-al-250-19-fuel-system-power-turbine-governor-to-control-fuel-tube-clamp-installation","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":41470,"registerId":"commonwealth-F2006B02240-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/AL 250/19 - Fuel System - Power Turbine Governor to Control Fuel Tube Clamp - Installation","content":"---\nmeta-content-style-type: text/css\nmeta-content-type: application/xhtml+xml; charset=utf-8\nmeta-description: CASA Airworthiness Directive\nmeta-generator: Aspose.Words for .NET 22.10.0\nmeta-keywords: Issue 9/1973,Turbine engines,Allison Turbine Engines - 250 Series,Fuel System - Power Turbine Governor to Control Fuel Tube Clamp - Installation,19\ntitle: Airworthiness Directive - AD/AL 250/19 - Fuel System - Power Turbine Governor to Control Fuel Tube Clamp - Installation\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)  Allison Turbine Engines - 250 Series\n\n \n\nAD/AL 250/19 Fuel System - Power Turbine Governor to\n\nControl Fuel Tube Clamp - Installation\n\n\n9/73\n\n \n\nApplicability: All 250-C20 CECO-Controlled Engine Assemblies prior to S/No. CAE 820908. Document:               Allison 250 CEB No. 1040, Rev. 1.\n\nCompliance: Within 50 hours’ time in service after 28 September 1973.\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":{"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The directive, as presented, sets a single, specific requirement for engines earlier than serial number CAE 820908 and a fixed compliance interval (50 hours after 28 September 1973). There is no indication within the supplied text that the applicability or required actions have been altered from the instrument’s stated terms."},"complexity_factors":["Narrow technical scope limited to one engine model and a serial-number cut-off (low scope breadth). (Applicability)","Single, short compliance window (50 hours TIS) simplifies timing but imposes scheduling pressure. (Compliance)","Compliance mechanism delegated to a single external manufacturer document (Allison 250 CEB No. 1040, Rev. 1) which concentrates technical detail outside the directive. (Document)","Clear regulatory authority and format (Part 39 airworthiness directive) reduces interpretive uncertainty. (Header)","Historic effective date (1973) may complicate practical relevance today but does not increase textual complexity."],"plain_english_summary":"This airworthiness directive requires owners/operators to retrofit a power‑turbine governor to Allison 250‑C20 CECO engines with serial numbers before CAE 820908, using the manufacturer’s Allison 250 CEB No.1040 Rev.1. Compliance is mandatory within 50 flight hours after 28 September 1973; costs and scheduling are the owner’s responsibility. The Civil Aviation Safety Authority enforces the requirement."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, single-issue airworthiness directive from 1973 addressing a specific mechanical defect. It has not expanded beyond its original narrow safety purpose."},"complexity_factors":["Very short document (under 200 words)","Only 4 defined elements: applicability, document reference, compliance deadline, and the specific engine models affected","No cross-references to other legislation beyond the enabling Civil Aviation Regulations 1998","Single, unambiguous compliance action with clear time limit","No conditional logic, exceptions, or nested provisions"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) that requires aircraft owners and operators to fix a specific mechanical problem.\n\n**What it does:**\nOrders the installation of a clamp on a fuel tube that runs between the Power Turbine Governor and the Control Fuel system on certain Allison 250 series turbine engines.\n\n**Who it affects:**\nAnyone operating aircraft with **Allison 250-C20 CECO-Controlled engines** with serial numbers **before CAE 820908**. These are commonly used in helicopters and light aircraft.\n\n**Why it matters:**\nLoose or unclamped fuel tubes can vibrate, chafe (wear through), or disconnect — creating fire hazards or engine failure. This AD mandates a specific safety fix within **50 flight hours** after 28 September 1973.\n\n**What must be done:**\nOperators must follow the manufacturer's instructions in **Allison Service Bulletin CEB No. 1040, Revision 1** to install the clamp."}},"importantCases":[],"_links":{"self":"/api/acts/ad-al-250-19-fuel-system-power-turbine-governor-to-control-fuel-tube-clamp-installation","history":"/api/acts/ad-al-250-19-fuel-system-power-turbine-governor-to-control-fuel-tube-clamp-installation/history","analysis":"/api/acts/ad-al-250-19-fuel-system-power-turbine-governor-to-control-fuel-tube-clamp-installation/analysis","conflicts":"/api/acts/ad-al-250-19-fuel-system-power-turbine-governor-to-control-fuel-tube-clamp-installation/conflicts","importantCases":"/api/acts/ad-al-250-19-fuel-system-power-turbine-governor-to-control-fuel-tube-clamp-installation/important-cases","documents":"/api/acts/ad-al-250-19-fuel-system-power-turbine-governor-to-control-fuel-tube-clamp-installation/documents"}}