{"id":"F2006B11245","name":"AD/M20/40 - Oil Pressure Transducer Installation - Modification","slug":"ad-m20-40-oil-pressure-transducer-installation-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":56965,"registerId":"commonwealth-F2006B11245-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/M20/40 - Oil Pressure Transducer Installation - 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)  Mooney M20 Series Aeroplanes\n\n \n\nAD/M20/40 Oil Pressure Transducer Installation - Modification 9/80\n\nApplicability: Model M20J with S/Nos. 24-0084, 24-0378 to 24-0906, 24-0908 to 24-0925, 24-0927\n\nto 24-0942 and 24-0946.\n\n \n\nDocument: Mooney SB M20-221.\n\n \n\nCompliance: Within 100 hours time in service after 30 November 1980.\n\n \n\nBackground:  Inadequate clearance between the oil pressure transducer housing and the upper right hand engine mount may cause the transducer to chafe through and lose all engine oil.\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":{"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The document itself sets a single corrective requirement for specified serial-numbered aircraft with a fixed compliance period and a reference to a service bulletin. The text contains no indication that the scope was broadened or narrowed relative to an earlier or different instrument; therefore no change of scope is evident in this text (Applicability; Compliance; Document)."},"complexity_factors":["Narrow, explicit applicability by make/model and specific serial numbers (Applicability)","Single, fixed compliance deadline measured in hours time in service (Compliance)","Dependence on an external technical document (Mooney SB M20-221) for how to carry out the modification (Document)","Clear, single-sentence safety rationale identifying the hazard (Background)","No procedural options, exemptions, or alternative compliance pathways included in the text"],"plain_english_summary":"Owners/operators of specified Mooney M20J serial numbers must install/modify the oil pressure transducer per Mooney Service Bulletin M20-221 within 100 hours TIS after 30 Nov 1980. The AD, issued by the Civil Aviation Safety Authority, mandates the preventive modification to eliminate transducer-to-engine-mount chafing that could cause loss of engine oil. Compliance, scheduling, parts and labor fall to the listed aircraft owners/operators, who must obtain and follow the referenced Service Bulletin for the detailed technical steps."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted safety directive addressing a specific mechanical defect in a narrow subset of aircraft. It has not expanded beyond its original purpose of mandating a single modification to prevent oil loss."},"complexity_factors":["Extremely short document (approximately 150 words of substantive content)","Only 4 operative sections: Applicability, Document reference, Compliance deadline, and Background","No defined terms section","No cross-references to other legislation beyond the parent Civil Aviation Regulations 1998","Simple conditional logic: if you own this specific aircraft model with these specific serial numbers, you must comply","Single technical reference to an external service bulletin (Mooney SB M20-221)","Clear, unambiguous compliance deadline (100 hours time in service after fixed date)"],"plain_english_summary":"**What this is:** This is an **Airworthiness Directive (AD)** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) that requires aircraft owners to fix a specific mechanical problem.\n\n**What it does:** It orders owners of certain **Mooney M20J aeroplanes** (specific serial numbers listed) to modify how the oil pressure transducer is installed. A transducer is a sensor that measures oil pressure and sends that information to the cockpit gauge.\n\n**Why it matters:** The original installation has **inadequate clearance** — meaning the sensor sits too close to the upper right engine mount. Vibration during flight can cause the sensor housing to rub (\"chafe\") against the mount until it wears through. If the sensor casing breaks open, **all engine oil can drain out**, leading to catastrophic engine failure.\n\n**Who must comply:** Owners/operators of Mooney M20J aircraft with these specific serial numbers:\n- 24-0084\n- 24-0378 through 24-0906\n- 24-0908 through 24-0925\n- 24-0927 through 24-0942\n- 24-0946\n\n**What they must do:** Follow the instructions in **Mooney Service Bulletin M20-221** to modify the installation.\n\n**When:** Within 100 hours of flight time after 30 November 1980.\n\n**The bottom line:** This is a **safety-critical fix** to prevent total engine oil loss and potential engine seizure. Non-compliance means the aircraft is not airworthy and cannot legally fly."}},"importantCases":[],"_links":{"self":"/api/acts/ad-m20-40-oil-pressure-transducer-installation-modification","history":"/api/acts/ad-m20-40-oil-pressure-transducer-installation-modification/history","analysis":"/api/acts/ad-m20-40-oil-pressure-transducer-installation-modification/analysis","conflicts":"/api/acts/ad-m20-40-oil-pressure-transducer-installation-modification/conflicts","importantCases":"/api/acts/ad-m20-40-oil-pressure-transducer-installation-modification/important-cases","documents":"/api/acts/ad-m20-40-oil-pressure-transducer-installation-modification/documents"}}