{"id":"F2006B08190","name":"AD/CESSNA 320/12 Amdt 1 - Turbocharger","slug":"ad-cessna-320-12-amdt-1-turbocharger","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":115398,"registerId":"commonwealth-F2006B08190-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/CESSNA 320/12 Amdt 1 - Turbocharger","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 320 Series Aeroplanes\n\nAD/CESSNA 320/12\n\nAmdt 1\n\n  \nTurbocharger 9/87\n\nApplicability: All models 320D, 320E, and 320F fitted with Continental model TSIO-520-B engines.\n\nRequirement: Remove the turbosupercharger turbine insulation blanket or stainless steel heat shields and visually inspect the complete surface of the TCM turbosupercharger assembly P/N 632729 (AID P/N 406610) for cracks, bulges, or burnt areas.\n\nNote: Turbine housings exhibiting any cracks, bulges, or burnt areas shall be replaced before further flight.\n\nCompliance: Prior to accumulating 425 hours total time in service and thereafter at each issue of a new Maintenance Release.\n\nBackground: This Airworthiness Directive was originally raised to reflect the requirement of FAA AD 70-3-4, effective 31 January 1970. This Amendment is raised to clarify the Requirement, and include reference to stainless steel heat shields, that were fitted beginning with 1972 models.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This amendment remains tightly scoped to its original purpose. The change from the original AD is minor and clarifying only - it adds 'stainless steel heat shields' to the inspection requirement to cover 1972 and later models that were fitted with these instead of insulation blankets. The core safety purpose (preventing turbocharger failures through visual inspection) and the affected aircraft population remain unchanged."},"complexity_factors":["Very short document (approximately 150 words)","Only 3 defined terms (Applicability, Requirement, Compliance)","No cross-references to other legislation beyond a single historical reference to FAA AD 70-3-4","Single straightforward requirement with clear trigger condition","No nested exceptions or conditional logic - damage found equals mandatory replacement","Specific part numbers and model numbers provided for precision but do not add interpretive complexity"],"plain_english_summary":"This is a **safety rule for specific Cessna aeroplanes** that tells aircraft owners and mechanics what they must do to keep the turbocharger (a part that boosts engine power) safe.\n\n**What it does:**\n- Requires regular **visual inspections** of the turbocharger on certain Cessna 320 models (320D, 320E, and 320F) with specific Continental engines\n- Mechanics must **remove insulation blankets or heat shields** to check the turbocharger surface for **cracks, bulges, or burnt areas**\n- If any damage is found, the turbocharger **must be replaced before the plane can fly again**\n\n**Who it affects:**\n- Owners and operators of Cessna 320D, 320E, and 320F aircraft with Continental TSIO-520-B engines\n- Licensed aircraft maintenance engineers who issue Maintenance Releases (official documents saying an aircraft is safe to fly)\n\n**When it must be done:**\n- **Before** the turbocharger reaches 425 hours of total use\n- **Repeatedly** at every new Maintenance Release (typically annual or 100-hourly inspections)\n\n**Why it matters:**\nTurbocharger failures can cause engine damage or in-flight emergencies. This rule prevents catastrophic failures by catching cracks and heat damage early. The rule was updated (Amendment 1) to include newer aircraft models that have stainless steel heat shields instead of just insulation blankets."},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":true,"description":"The Amendment clarifies the existing Requirement and explicitly adds reference to stainless steel heat shields fitted from 1972 models, expanding the text of the inspection step to cover those shields. The underlying directive to inspect the TCM turbosupercharger assembly and to replace turbine housings with cracks, bulges or burnt areas remains, but the clarified reference to stainless steel heat shields alters the practical set of parts that must be removed and inspected. (Background; Requirement)"},"complexity_factors":["Limited applicability to specific airframe models and a single engine model (Applicability)","Single, plainly defined inspection task (remove insulation/heat shields and visually inspect) with objective defect criteria: cracks, bulges, burnt areas (Requirement)","Clear remediation mandatory if defects found (replace turbine housing before further flight) (Requirement)","Defined timing for first and repeat inspections (prior to 425 hours total time in service and at each new Maintenance Release) which creates an ongoing scheduling requirement (Compliance)","Amendment removes ambiguity about which heat‑shielding must be removed (Requirement; Background) which simplifies compliance but requires checking different shield types"],"plain_english_summary":"This directive mandates removal of insulation or stainless steel heat shields to visually inspect the TCM turbosupercharger assembly (P/N 632729) for cracks, bulges or burnt areas and requires replacement of any defective turbine housing before further flight. It applies to Cessna 320D/E/F aircraft with Continental TSIO‑520‑B engines; the first check is before 425 hours TTS and then at each new Maintenance Release. Compliance and replacement costs fall to owners/operators; the amendment clarifies inclusion of post‑1972 heat shields."}},"importantCases":[],"_links":{"self":"/api/acts/ad-cessna-320-12-amdt-1-turbocharger","history":"/api/acts/ad-cessna-320-12-amdt-1-turbocharger/history","analysis":"/api/acts/ad-cessna-320-12-amdt-1-turbocharger/analysis","conflicts":"/api/acts/ad-cessna-320-12-amdt-1-turbocharger/conflicts","importantCases":"/api/acts/ad-cessna-320-12-amdt-1-turbocharger/important-cases","documents":"/api/acts/ad-cessna-320-12-amdt-1-turbocharger/documents"}}