{"id":"F2006B06666","name":"AD/ROTAX/19 - Oil Dipstick","slug":"ad-rotax-19-oil-dipstick","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":48628,"registerId":"commonwealth-F2006B06666-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"AIRWORTHINESS DIRECTIVE","sectionType":"part","heading":"AIRWORTHINESS DIRECTIVE","content":"# AIRWORTHINESS DIRECTIVE\n\n![](image.001.png)  \n\nFor the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.1 (1) of CASR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.\n\n![](image.001.png)  \n\nRotax Piston Engines","sortOrder":0},{"sectionNumber":"AD/ROTAX/19 Oil Dipstick 12/2003","sectionType":"part","heading":"AD/ROTAX/19 Oil Dipstick 12/2003","content":"# AD/ROTAX/19 Oil Dipstick 12/2003\n\nApplicability: The following engines fitted with oil dipstick Part Number (P/N) 965150: Rotax 912 A series engines Serial Number (S/N) up to 4,410.606 inclusive; and 912 F-series engines S/N up to 4,412.858 inclusive; and\n\n912 S-series engines S/N up to 4,922.971 inclusive; and 914 F-series engines S/N up to 4,420.394 inclusive.\n\nRequirement: Replace oil dipstick P/N 956150 with P/N 956151 in accordance with Bombardier Rotax Service Bulletin (S/B) SB-912-040R1 or SB-914-026R1 as required.\n\nNote: Austrian AD No 116 refers.\n\nCompliance: At the next oil change or prior to 1 January 2004, whichever occurs first. This Airworthiness Directive becomes effective on 27 November 2003.\n\nBackground: A slower than normal return oil flow from the crankcase to the oil tank can be experienced under certain conditions. This may result in the oil tank level going below minimum levels. Low oil levels in the oil tank can allow air to enter the oil system, causing damage to the valve mechanism and possible engine stoppage.\n\n![Signature of Jim Coyne Delegate of the Civil Aviation Safety Authority](image.002.png)  \n\nJim Coyne\n\nDelegate of the Civil Aviation Safety Authority 14 October 2003\n\n![](image.001.png)","sortOrder":1}],"analysis":{"flash_summary_failed":{"failed":true,"reason":"A positive credit balance is required for all requests, including BYOK, so fallback providers remain available. Add credits at https://vercel.com/d?to=%2F%5Bteam%5D%2F%7E%2Fai%3Fmodal%3Dtop-up to continue.","source":"analysis-cron"},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The AD is narrowly targeted to correct a specific unsafe condition (slow oil return/low oil level due to a dipstick issue) by mandating a particular part replacement. It does not broaden regulatory responsibilities beyond that safety remedy. There is no evidence in the text that the instrument has grown beyond that original, component-focused purpose."},"complexity_factors":["Short, single-issue directive focused on one component replacement","Applicability determined by engine model and serial-number ranges (four engine families)","One operational deadline: at next oil change or prior to 1 January 2004","Cross-reference to two external service bulletins (SB-912-040R1, SB-914-026R1) for implementation details","Reference to an external foreign AD (Austrian AD No 116)","Textual inconsistency in part numbers between Applicability (P/N 965150) and Requirement (replace P/N 956150 with P/N 956151) introduces minor ambiguity"],"plain_english_summary":"**What this directive does (in plain English)**\n\n- This Airworthiness Directive (AD) orders the replacement of a specific oil dipstick part fitted to certain Rotax piston engines. It is a safety instruction issued under the Civil Aviation Safety Regulations.\n\n**Who it affects**\n\n- Aircraft owners/operators and maintenance organisations that operate or maintain the following Rotax engines when fitted with the specified dipstick part number:\n  - Rotax 912 A-series (S/N up to 4,410.606 inclusive)\n  - Rotax 912 F-series (S/N up to 4,412.858 inclusive)\n  - Rotax 912 S-series (S/N up to 4,922.971 inclusive)\n  - Rotax 914 F-series (S/N up to 4,420.394 inclusive)\n\n  The AD applies only when the engine has the dipstick identified in the AD (see \"Requirement\" below).\n\n**What you must do**\n\n- Replace the oil dipstick with the new part number specified by the AD. The replacement must be done in accordance with the relevant Bombardier Rotax Service Bulletin (SB-912-040R1 or SB-914-026R1) (Requirement).\n\n- The replacement must occur at the next oil change or before 1 January 2004, whichever comes first. The AD became effective 27 November 2003 (Compliance).\n\n**Why the change was required (the safety problem)**\n\n- The manufacturer and regulator observed that, under certain conditions, oil can return too slowly from the engine crankcase to the oil tank. That slow return can let the oil-tank level fall below minimum, allow air into the oil system, damage valve mechanisms and could lead to engine stoppage (Background).\n\n**Mechanics and authority**\n\n- The AD is issued under subregulation 39.1(1) of the Civil Aviation Safety Regulations 1998, which gives the CASA delegate power to require corrective action for unsafe conditions. The AD refers to Bombardier Rotax service instructions for the exact replacement procedure (Requirement).\n\n**Who pays and who decides**\n\n- Aircraft owners/operators and their maintenance providers bear the cost of the replacement parts and labour. The CASA delegate is the decision-maker enforcing the AD under CASR authority (as indicated in the AD preamble).\n\n**Practical implications and implementation risks**\n\n- Operational timing: owners must plan the replacement at the next oil service or immediately if that would otherwise be after 1 January 2004.\n\n- Documentation/dependency: Compliance requires following the Bombardier Rotax service bulletins named in the AD. Those service documents provide the technical steps and parts details.\n\n- Ambiguity risk: the AD text shows inconsistent dipstick part numbers (the Applicability paragraph names P/N 965150, while the Requirement says replace P/N 956150 with P/N 956151). That inconsistency creates some ambiguity for implementers and increases the need to rely on the referenced Rotax service bulletins or direct regulatory/technical clarification before proceeding.\n\n**Trade-offs and costs**\n\n- The action is narrowly targeted to remove a component suspected of contributing to an oil-flow problem. The likely direct costs are the replacement part and labour. The AD reduces the risk of engine damage and in-service engine stoppage but imposes a short-term maintenance cost and administrative compliance burden on affected operators.\n\n**Cross-references**\n\n- The AD notes an equivalent Austrian AD (Austrian AD No 116) and requires compliance with Bombardier Rotax service bulletins SB-912-040R1 or SB-914-026R1 as appropriate (Requirement / Note).\n\n(References: Applicability, Requirement, Compliance, Background sections of the AD.)"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a targeted safety directive addressing a specific mechanical defect in specific engine models. The scope remains precisely limited to the identified unsafe condition and affected products."},"complexity_factors":["Single, specific mechanical action required (dipstick replacement)","Limited applicability: only 4 specific engine series with defined serial number ranges","Clear compliance deadline with simple alternative trigger (next oil change OR fixed date)","No nested conditions, exceptions, or cross-references to other legislation beyond a single reference to Austrian AD No 116","Short document (approximately 250 words) with straightforward structure: Applicability → Requirement → Compliance → Background"],"plain_english_summary":"This safety order requires owners/operators of certain Rotax 912 (A/F/S) and 914 F-series piston engines fitted with the old-style oil dipstick (P/N 965150) to replace it with the new dipstick (P/N 965151) per the manufacturer's service bulletin.  \n\nDo the replacement at the next oil change or before 1 January 2004, because slow oil drainage can let air into the oil system and lead to valve damage or engine failure in flight."}},"importantCases":[],"_links":{"self":"/api/acts/ad-rotax-19-oil-dipstick","history":"/api/acts/ad-rotax-19-oil-dipstick/history","analysis":"/api/acts/ad-rotax-19-oil-dipstick/analysis","conflicts":"/api/acts/ad-rotax-19-oil-dipstick/conflicts","importantCases":"/api/acts/ad-rotax-19-oil-dipstick/important-cases","documents":"/api/acts/ad-rotax-19-oil-dipstick/documents"}}