{"id":"F2006B05136","name":"AD/CESSNA 185/44 - Instrument Panel Light Dimming Rheostat","slug":"ad-cessna-185-44-instrument-panel-light-dimming-rheostat","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":45192,"registerId":"commonwealth-F2006B05136-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/CESSNA 185/44 - Instrument Panel Light Dimming Rheostat","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nCessna 185 Series Aeroplanes\n\nAD/CESSNA 185/44 Instrument Panel Light Dimming Rheostat 3/94\n\nApplicability: Cessna Model 185D, 185E and 185F aircraft with serial numbers 185-0777 through 18502310 inclusive.\n\nRequirement: Unless previously accomplished, replace the existing instrument panel light dimming rheostat (some installations will also require the fitting of a doubler) in accordance with the Accomplishment Instructions of Cessna Single Engine Service Bulletin SEB92-33 Revision 2 dated 10 September 1993.\n\nNote: FAA AD 93-24-15 Amdt 39-8764 refers.\n\nCompliance: Prior to 3 October 1994.\n\nBackground: The FAA has advised of a report of an inflight fire in a Cessna Model 172.\n\nThe fire was caused by a short in the electrical wiring controlled by the instrument panel light dimming rheostat. This Directive requires the rheostat to be replaced with an improved version, which is both current-limiting and heat-protected, thus decreasing the probability of an inflight fire being caused by a defective rheostat.","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The instrument imposes a mandatory equipment-replacement requirement for a defined set of aircraft; it does not expand or narrow the population affected beyond the serial-number list or alter the nature of regulatory powers. The directive enforces corrective action specified by the referenced service bulletin with a fixed compliance date."},"complexity_factors":["Narrow applicability limited to specific Cessna 185 serial-number range","Single, discrete technical action: replace rheostat (and install doubler if needed)","Reference to an external service bulletin (SEB92-33 Rev 2) for accomplishment instructions","Fixed compliance date creates a clear, time-limited enforcement obligation","Cross-reference to FAA AD adds administrative tracing but no additional procedural layers","Low regulatory discretion — mandatory requirement rather than optional guidance"],"plain_english_summary":"Requires owners/operators of Cessna 185D, 185E and 185F (serials 185-0777 through 18502310) to replace the instrument-panel light dimming rheostat with an improved, current-limiting, heat-protected unit per Cessna Service Bulletin SEB92-33 Rev 2, and fit a doubler where required. Compliance was required before 3 October 1994. The stated purpose is to reduce the risk of an inflight fire from a rheostat-related wiring short. Operators bear parts and labour costs and must follow the service bulletin's instructions by the deadline."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted safety directive addressing a specific known defect in specific aircraft. It has not expanded beyond its original purpose of preventing inflight fires caused by a faulty rheostat."},"complexity_factors":["Single, specific mechanical requirement (replace one component)","Limited applicability (three specific aircraft models with defined serial number range)","No defined terms section or interpretation provisions","No conditional logic or nested exceptions — straightforward compliance obligation","Short document (approximately 150 words of substantive content)","Single cross-reference to FAA directive and Cessna service bulletin for technical instructions"],"plain_english_summary":"This Airworthiness Directive mandates owners/operators of certain Cessna 185 D/E/F aircraft (specific serial ranges) to replace the instrument-panel light dimming rheostat — and, where required, fit a reinforcing doubler — because the original rheostat can overheat and cause inflight fires.  \n\nCompliance was mandatory (no legal flight until modified) and required completion by 3 October 1994."}},"importantCases":[],"_links":{"self":"/api/acts/ad-cessna-185-44-instrument-panel-light-dimming-rheostat","history":"/api/acts/ad-cessna-185-44-instrument-panel-light-dimming-rheostat/history","analysis":"/api/acts/ad-cessna-185-44-instrument-panel-light-dimming-rheostat/analysis","conflicts":"/api/acts/ad-cessna-185-44-instrument-panel-light-dimming-rheostat/conflicts","importantCases":"/api/acts/ad-cessna-185-44-instrument-panel-light-dimming-rheostat/important-cases","documents":"/api/acts/ad-cessna-185-44-instrument-panel-light-dimming-rheostat/documents"}}