{"id":"F2006B08245","name":"AD/CESSNA 337/26 - Oxygen Indicator Lights - Modification","slug":"ad-cessna-337-26-oxygen-indicator-lights-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":115514,"registerId":"commonwealth-F2006B08245-current","compilationNumber":null,"startDate":"2026-04-03","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/CESSNA 337/26 - Oxygen Indicator Lights - Modification","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 337 Series Aeroplanes\n\nAD/CESSNA 337/26 Oxygen Indicator Lights \\- Modification 12/81\n\nApplicability: All T337 series with a solid state chemical oxygen system installed.\n\nRequirement: Install a press to test system in the oxygen indicator light circuits so that the indicator lights can be tested prior to each flight.\n\nCompliance: Within 200 hours time in service or before the aircraft is cleared to operate to 23,000 feet maximum altitude after additional supplementary oxygen is installed to comply with ANO 20.4.\n\nBackground: The chemical oxygen system in Cessna aircraft has been reviewed by the Flying Operations Branch and additional supplementary oxygen is considered necessary to meet the requirements of ANO 20.4. The addition of the press to test system for the oxygen indicator lights is considered a satisfactory method for meeting the requirement of ANO 20.4, para. 4.1.","sortOrder":0}],"analysis":{"kimi_summary":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":1379},"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This directive maintains its original narrow technical scope. It addresses a specific airworthiness issue regarding oxygen indicator testing capability in Cessna T337 aircraft, with no evidence of expansion beyond the original equipment modification requirement."},"complexity_factors":["Single, specific technical requirement with no subsections or alternatives","Limited applicability restricted to one aircraft model (Cessna T337) with specific equipment","Simple compliance condition with clear numerical threshold (200 hours)","Only one external reference (ANO 20.4) with no nested cross-references"],"plain_english_summary":"This airworthiness directive requires owners/operators of Cessna T337s equipped with a solid‑state chemical oxygen system to install a press‑to‑test function on the oxygen warning-light circuits. You must fit the test capability within 200 flight hours, or before any flight above 23,000 ft when also fitting supplementary oxygen under ANO 20.4. It ensures pilots can verify oxygen warning lights preflight, improving safety on high‑altitude operations."}},"importantCases":[],"_links":{"self":"/api/acts/ad-cessna-337-26-oxygen-indicator-lights-modification","history":"/api/acts/ad-cessna-337-26-oxygen-indicator-lights-modification/history","analysis":"/api/acts/ad-cessna-337-26-oxygen-indicator-lights-modification/analysis","conflicts":"/api/acts/ad-cessna-337-26-oxygen-indicator-lights-modification/conflicts","importantCases":"/api/acts/ad-cessna-337-26-oxygen-indicator-lights-modification/important-cases","documents":"/api/acts/ad-cessna-337-26-oxygen-indicator-lights-modification/documents"}}