{"id":"F2006B08401","name":"AD/CESSNA 500/27 Amdt 1 - Aircraft Flight Manual, Flight into Icing Conditions","slug":"ad-cessna-500-27-amdt-1-aircraft-flight-manual-flight-into-icing-conditions","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":115851,"registerId":"commonwealth-F2006B08401-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"AIRWORTHINESS DIRECTIVE","sectionType":"part","heading":"AIRWORTHINESS DIRECTIVE","content":"# AIRWORTHINESS DIRECTIVE\n\n![](image.002.png)\n\n![](image.002.png)  \nFor the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/CESSNA 500/27 and issues the following AD under subregulation 39.1 (1) of CAR 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.","sortOrder":0},{"sectionNumber":"AD/CESSNA 500/27","sectionType":"part","heading":"AD/CESSNA 500/27","content":"# AD/CESSNA 500/27\n\nAmdt 1\n\n  \n\nAircraft Flight Manual, Flight into Icing Conditions\n\n  \n7/2000","sortOrder":1},{"sectionNumber":"\"WARNING\"","sectionType":"part","heading":"\"WARNING\"","content":"# \"WARNING\"\n\nSevere icing may result from environmental conditions outside of those for which the aircraft is certificated.\n\nFlight in freezing rain, freezing drizzle, or mixed icing conditions (super cooled liquid water and ice crystals) may result in:\n\n    ice build-up on protected surfaces and exceed the capability of the ice protection system, or\n\n    ice forming aft of the protected surfaces.\n\nThis ice may not be shed using the ice protection systems, and may seriously degrade the performance and controllability of the aircraft.\n\nDuring flight, severe icing conditions that exceed those for which the aircraft is certificated shall be determined by the visual cues described below. If one or more of these visual cues exists, immediately request priority handling from Air Traffic Control to facilitate a route or an altitude change to exit the icing conditions. The cues are:\n\n    unusually extensive ice accumulation on the airframe and windscreen in areas not normally observed to collect ice, and/or\n\n    accumulation of ice on the upper surface of the wing aft of the protected area.","sortOrder":2},{"sectionNumber":"THE FOLLOWING WEATHER CONDITIONS MAY BE ","sectionType":"part","heading":"THE FOLLOWING WEATHER CONDITIONS MAY BE CONDUCIVE TO SEVERE IN-FLIGHT ICING:","content":"# THE FOLLOWING WEATHER CONDITIONS MAY BE CONDUCIVE TO SEVERE IN-FLIGHT ICING:\n\n    Visible rain at temperatures below 0 degrees Celsius ambient air temperature;\n    Droplets that splash or splatter on impact at temperatures below 0 degrees Celsius ambient air temperature.","sortOrder":3},{"sectionNumber":"PROCEDURES FOR EXITING A SEVERE ICING","sectionType":"part","heading":"PROCEDURES FOR EXITING A SEVERE ICING","content":"# PROCEDURES FOR EXITING A SEVERE ICING\n\nENVIRONMENT: (These procedures are applicable to all flight phases from take-off to landing.)\n\nMonitor the ambient air temperature.\n\nWhile severe icing may form at temperatures as cold as \\-18 degrees Celsius, increased vigilance is warranted at temperatures around freezing when visible moisture is present.","sortOrder":4}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"The instrument explicitly revokes the earlier AD and issues an amended AD (\"revokes Airworthiness Directive (AD) AD/CESSNA 500/27 and issues the following AD\"), thereby replacing the prior directive. Mechanically, it continues to target the same unsafe condition (flight into icing) but shifts obligations onto operators and crews to update the Aircraft Flight Manual and follow prescribed in‑flight procedures and visual-cue guidance (see \"WARNING\" and \"PROCEDURES FOR EXITING A SEVERE ICING\"). This replaces the previous wording and imposes clarified operational duties (monitor ambient temperature, request ATC priority, exit route/altitude changes) while leaving some judgement to crew visual assessment."},"complexity_factors":["Formality of regulatory action: revocation of a prior AD and issuance of an amended AD increases procedural steps for regulators and operators (\"revokes Airworthiness Directive (AD) AD/CESSNA 500/27 and issues the following AD\").","Technical content: requires pilot recognition of specific icing visual cues and understanding of meteorological terms (\"unusually extensive ice accumulation\", \"upper surface of the wing aft of the protected area\").","Operational compliance: imposes in‑flight behavioural requirements (monitor ambient temperature, request ATC priority, change route/altitude) applicable at all flight phases (\"These procedures are applicable to all flight phases\").","Ambiguity in thresholds: no numeric icing accumulation limits for 'severe' are given; reliance on visual cues and ambient temperature increases subjective judgment by pilots.","Delegated enforcement discretion: AD issued under CASA delegate power under CAR 1998 subregulation 39.1(1), leaving implementation timing and specific corrective instructions to the requirement/compliance sections.","Limited cross-referencing: the AD refers to actions in a 'requirement section' without reproducing detailed technical procedures in the supplied text, creating a need to consult the full AD text/manual amendments."],"plain_english_summary":"This AD revokes the prior AD and issues an amended directive requiring updates to the Aircraft Flight Manual and crew procedures for flight into icing conditions for Cessna 500 aircraft. It sets visual cues for when icing exceeds certification limits, lists weather likely to cause severe icing (e.g. freezing rain), and prescribes immediate actions to exit those conditions. The rule affects aircraft owners/operators and flight crews by imposing procedural and manual-change obligations to address an identified unsafe condition."},"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"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This amendment maintains the original scope — safety requirements for Cessna 500 aircraft operating in icing conditions. It appears to be a straightforward update (possibly clarifying warning language or procedures) rather than an expansion into new operational areas or aircraft types."},"complexity_factors":["Very short document (approximately 400 words)","No defined terms section — uses plain language throughout","No cross-references to other legislation beyond a single mention of CAR 1998 subregulation 39.1(1) (the enabling power)","Simple structure: warning, weather conditions, procedures — no nested conditions or exceptions","Single regulatory mechanism: revoke old AD, issue new AD with mandatory actions","No conditional compliance timelines or alternative methods of compliance described"],"plain_english_summary":"This AD replaces an earlier directive for Cessna 500 series jets to address deadly exposure to severe icing (freezing rain, freezing drizzle, mixed ice) that can overwhelm ice-protection systems. It makes mandatory that pilots recognize unusual ice accumulation, monitor outside air temperature near freezing with visible moisture, and immediately request priority ATC assistance to change altitude or route to escape such conditions. It affects owners, operators, pilots and maintenance organizations and enforces escape procedures after fatal accidents."}},"importantCases":[],"_links":{"self":"/api/acts/ad-cessna-500-27-amdt-1-aircraft-flight-manual-flight-into-icing-conditions","history":"/api/acts/ad-cessna-500-27-amdt-1-aircraft-flight-manual-flight-into-icing-conditions/history","analysis":"/api/acts/ad-cessna-500-27-amdt-1-aircraft-flight-manual-flight-into-icing-conditions/analysis","conflicts":"/api/acts/ad-cessna-500-27-amdt-1-aircraft-flight-manual-flight-into-icing-conditions/conflicts","importantCases":"/api/acts/ad-cessna-500-27-amdt-1-aircraft-flight-manual-flight-into-icing-conditions/important-cases","documents":"/api/acts/ad-cessna-500-27-amdt-1-aircraft-flight-manual-flight-into-icing-conditions/documents"}}