{"id":"F2006B08406","name":"AD/CESSNA 500/6 - Oxygen Mask Door Actuating Piston - Replacement","slug":"ad-cessna-500-6-oxygen-mask-door-actuating-piston-replacement","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":115861,"registerId":"commonwealth-F2006B08406-current","compilationNumber":null,"startDate":"2026-04-03","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/CESSNA 500/6 - Oxygen Mask Door Actuating Piston - Replacement","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)  Cessna 500 (Citation) Series Aeroplanes\n\n \n\nAD/CESSNA 500/6 Oxygen Mask Door Actuating\n\nPiston - Replacement Applicability: All models with S/Nos. 500-0041 to 500-0065 except S/No. 500-0063. Document:               Cessna Citation SL35-1 and Puritan-Zep SB dated 15 March 1973.\n\nCompliance: Before 29 March 1974.\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\n \n\n \n\n \n\n\n3/74\n","sortOrder":0}],"analysis":{"kimi_summary":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":1722},"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"The directive remains tightly scoped to its original purpose: remedying a specific mechanical defect in a single component on a defined range of aircraft. There is no evidence of scope expansion into broader operational requirements or additional aircraft types."},"complexity_factors":["Single, discrete maintenance action required","Narrow applicability limited to 24 specific aircraft serial numbers","No nested exceptions or conditional logic (only one excluded serial number)","External technical references require consulting separate manufacturer documents","Absolute compliance date with no alternative methods stated"],"plain_english_summary":"**What it does:** This is a safety order (an Airworthiness Directive) requiring the replacement of a specific mechanical part on certain Cessna business jets.\n\n**Who it affects:** Owners and operators of Cessna 500 (Citation) series aircraft with serial numbers 500-0041 through 500-0065, **except** serial number 500-0063.\n\n**The requirement:** You must replace the **oxygen mask door actuating piston** — the small device that physically pushes open the door covering the emergency oxygen masks. If this piston fails, the door won't open during a loss of cabin pressure, blocking access to life-saving oxygen.\n\n**Compliance deadline:** The replacement had to be completed before 29 March 1974.\n\n**How to comply:** Follow the instructions in Cessna Service Letter SL35-1 and the Puritan-Zep Service Bulletin dated 15 March 1973."}},"importantCases":[],"_links":{"self":"/api/acts/ad-cessna-500-6-oxygen-mask-door-actuating-piston-replacement","history":"/api/acts/ad-cessna-500-6-oxygen-mask-door-actuating-piston-replacement/history","analysis":"/api/acts/ad-cessna-500-6-oxygen-mask-door-actuating-piston-replacement/analysis","conflicts":"/api/acts/ad-cessna-500-6-oxygen-mask-door-actuating-piston-replacement/conflicts","importantCases":"/api/acts/ad-cessna-500-6-oxygen-mask-door-actuating-piston-replacement/important-cases","documents":"/api/acts/ad-cessna-500-6-oxygen-mask-door-actuating-piston-replacement/documents"}}