{"id":"F2006B06671","name":"AD/ROTAX/5 - Carburettor Contamination","slug":"ad-rotax-5-carburettor-contamination","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":48648,"registerId":"commonwealth-F2006B06671-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/ROTAX/5 - Carburettor Contamination","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 106 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nRotax Piston Engines\n\nAD/ROTAX/5 Carburettor Contamination 11/96\n\nApplicability: All Rotax 912 series engines up to and including engine serial number 4,076.244 and/or carburettor serial number 00151.\n\nRequirement: Examine the carburettor as per the requirements of Bombardier Rotax Technical Bulletin 912-09 dated 30 August 1995.\n\nNote: Austro Control (Austria) AD 83 dated 12 September 1995 refers.\n\nCompliance: Within 10 hours time in service from 10 October 1996.\n\nBackground: Bombardier Rotax have reported that several carburettors have been found with contamination in the float chamber. This Directive requires examination of the carburettor to prevent the possibility of partial or complete blockage of the idle or main jet leading to poor performance or stoppage of the engine.","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The directive’s scope aligns with the stated original intent in the document: to inspect affected carburettors on Rotax 912 series engines (identified by specific engine and carburettor serial numbers) to prevent jet blockage and associated engine performance problems or stoppage. The Requirement and Applicability sections implement that stated purpose (Requirement; Applicability; Background)."},"complexity_factors":["Narrow, clearly defined applicability by engine and carburettor serial numbers (Applicability) — reduces scope complexity","Mandates following an external technical bulletin (Bombardier Rotax Technical Bulletin 912-09) for procedural detail (Requirement) — adds dependence on an external document","Short fixed compliance window (10 hours time in service from a stated date) creates scheduling pressure (Compliance)","Does not specify remedial actions or costs if contamination is found (Requirement; Background) — leaves practical decisions to owners/operators and maintenance providers"],"plain_english_summary":"This Airworthiness Directive requires owners/operators of aircraft with Rotax 912 series engines (engine S/Ns up to 4,076.244 and/or carburettor S/Ns up to 00151) to inspect the carburettor per Bombardier Rotax Technical Bulletin 912‑09 within 10 hours TIS from 10 October 1996. It responds to reported carburettor contamination that could block jets, risking poor performance or engine stoppage; inspection costs and any repairs fall to the owner/operator."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, time-bound safety directive with a narrow, specific scope. It addresses a single identified defect in specific engine models and does not represent scope creep from any original intent."},"complexity_factors":["Single, specific maintenance task with clear applicability criteria","Only 2 defined applicability criteria (engine serial number and/or carburettor serial number)","No nested exceptions or conditional logic","Single cross-reference to manufacturer technical bulletin and one foreign aviation directive","Very short document (under 200 words)","Clear compliance deadline (10 hours time in service from fixed date)"],"plain_english_summary":"This is an **Airworthiness Directive** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) that requires specific maintenance action on aircraft engines.\n\n**What it does:**\nOrders owners and operators of certain **Rotax 912 series aircraft engines** to inspect their carburettors (the device that mixes fuel and air) for contamination. The inspection must follow a specific technical bulletin from the engine manufacturer (Bombardier Rotax).\n\n**Who it affects:**\nAnyone with a Rotax 912 engine with a serial number up to 4,076,244, or a carburettor with serial number 00151 or lower. These are commonly used in light aircraft, ultralights, and recreational planes.\n\n**Why it matters:**\nContamination in the carburettor's float chamber can block fuel jets, causing **engine failure or poor performance** — obviously dangerous when flying. This directive was issued after the manufacturer reported multiple cases of contaminated carburettors.\n\n**What must be done:**\n- **When:** Within 10 hours of flying time after 10 October 1996\n- **How:** Follow the manufacturer's technical bulletin (912-09, dated 30 August 1995)\n- **Reference:** Also relates to an Austrian aviation safety directive (Austro Control AD 83)"}},"importantCases":[],"_links":{"self":"/api/acts/ad-rotax-5-carburettor-contamination","history":"/api/acts/ad-rotax-5-carburettor-contamination/history","analysis":"/api/acts/ad-rotax-5-carburettor-contamination/analysis","conflicts":"/api/acts/ad-rotax-5-carburettor-contamination/conflicts","importantCases":"/api/acts/ad-rotax-5-carburettor-contamination/important-cases","documents":"/api/acts/ad-rotax-5-carburettor-contamination/documents"}}