{"id":"F2006B05228","name":"AD/CESSNA 206/24 - Goodyear Fuel Cells","slug":"ad-cessna-206-24-goodyear-fuel-cells","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":45502,"registerId":"commonwealth-F2006B05228-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/CESSNA 206/24 - Goodyear Fuel Cells","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 206 Series Aeroplanes\n\n \n\nAD/CESSNA 206/24 Goodyear Fuel Cells 6/78\n\nApplicability: All models 206, P206, U206 and TU206 fitted with Goodyear BTC-39 fuel cells. Requirement:               Action in accordance with Cessna SL No. SE78-10.\n\nCompliance: Within 100 hours time in service after 30 June 1978 and annually thereafter as detailed in Cessna SL No. SE78-10.\n\n \n","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The directive as written applies specifically to Cessna 206-series aeroplanes fitted with Goodyear BTC-39 fuel cells and makes compliance with Cessna SL No. SE78-10 mandatory on the schedule stated. The text does not indicate any expansion or narrowing of that applicability or of required actions compared with the directive itself; it simply imposes the manufacturer's service-letter actions on that defined set of aircraft (Applicability, Requirement, Compliance)."},"complexity_factors":["Reference to an external technical document (Cessna SL No. SE78-10) for the substance of the required work increases practical complexity because the AD does not specify the technical steps.","Time-based compliance schedule (100 hours after a fixed date and annual thereafter) requires ongoing record-keeping and scheduling by operators.","Narrow applicability (specific models fitted with a specific fuel cell model) concentrates compliance obligations but requires accurate configuration checks to determine applicability.","Enforcement depends on regulator interpretation of compliance with an external service letter, leaving limited room for alternative compliance without further approvals.","Historic effective date (30 June 1978) may complicate interpretation for aircraft with incomplete historical records."],"plain_english_summary":"# What this directive does\n\n- This is an airworthiness directive titled \"AD/CESSNA 206/24 — Goodyear Fuel Cells\" applying to Cessna 206-series aeroplanes that are fitted with Goodyear BTC-39 fuel cells. (Applicability)\n\n- It requires operators to carry out the specific actions set out in Cessna Service Letter No. SE78-10. The directive does not reproduce those actions itself; it makes compliance with that service letter mandatory. (Requirement)\n\n- The timing requirement is: carry out the required action within 100 hours time-in-service after 30 June 1978, and then repeat the actions annually thereafter in the manner described in the service letter. (Compliance)\n\n# Who this affects\n\n- Owners and operators of Cessna 206, P206, U206 and TU206 aircraft that have Goodyear BTC-39 fuel cells installed. (Applicability)\n\n- Maintenance organisations and licensed engineers who perform the work specified in Cessna SL No. SE78-10, because they will perform and document the required work. (Requirement)\n\n# Who decides and who enforces\n\n- The Civil Aviation Safety Authority (CASA) issues the directive and enforces compliance. The mandatory technical content is set by the referenced Cessna service letter, so the aircraft manufacturer’s document determines the precise technical steps to be taken. (Requirement)\n\n# What people and organisations must do (behavioural change)\n\n- Inspect, modify, repair or replace parts of the fuel cell system as specified in Cessna SL No. SE78-10 within the first 100 hours TIS after 30 June 1978, and then follow the same service letter on an annual schedule thereafter. (Requirement, Compliance)\n\n# Who pays and what costs are involved\n\n- Direct costs fall on aircraft owners/operators and on maintenance providers: labour time, parts, and any downtime while work is done. (Requirement, Compliance)\n\n- Additional indirect costs can include scheduling and record-keeping to meet the 100-hour and annual timing, and potential productivity loss if aircraft are grounded for inspection/repair. (Compliance)\n\n# Incentives, trade-offs and implementation risks\n\n- The directive transfers the decision about the precise technical remedy to the manufacturer’s service letter: operators must follow that external document rather than relying on the AD text alone. That creates a dependency on Cessna SL No. SE78-10 for scope and method of work. (Requirement)\n\n- Because the AD sets specific timing (100 hours after 30 June 1978 and annual thereafter), operators face a clear compliance schedule; this reduces discretionary delay but imposes recurring costs. (Compliance)\n\n- Enforcement rests with the regulator; failure to follow the service letter as made mandatory by the AD exposes operators to enforcement action. The AD itself does not set tolerances or alternative compliance paths — those would appear only in the service letter or in separate approvals. (Requirement)\n\n- The AD is narrowly targeted by aircraft model and fuel-cell type, so the direct burden is concentrated on a specific subset of aircraft while benefits (safety outcomes claimed by regulator or manufacturer) would be distributed across users of those aircraft. (Applicability)\n\n# Practical notes for affected operators\n\n- Read Cessna Service Letter No. SE78-10 in full to know the exact actions required; the AD binds you to that document. (Requirement)\n\n- Make arrangements for the required work within the 100-hour window measured from 30 June 1978 and for annual repeats thereafter; keep maintenance records showing compliance. (Compliance)\n\n(References in this summary refer to the labeled parts of the directive: Applicability, Requirement, Compliance.)"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, single-issue airworthiness directive from 1978 addressing a specific fuel cell model in specific aircraft. It has not expanded beyond its original narrow safety purpose."},"complexity_factors":["Very short document — only 4 substantive paragraphs","No defined terms section; all terms are standard aviation terminology","Single cross-reference to external document (Cessna SL No. SE78-10)","Simple conditional structure: applicability criteria + single compliance requirement","No nested exceptions or complex logical operators"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — essentially a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA). It applies to specific **Cessna 206 series aircraft** (models 206, P206, U206, and TU206) that are fitted with **Goodyear BTC-39 fuel cells**.\n\n**What it requires:**\n- Aircraft owners and operators must follow the instructions in **Cessna Service Letter No. SE78-10** — a technical bulletin from the manufacturer.\n\n**When to comply:**\n- First inspection: within **100 hours of flying time** after 30 June 1978\n- **Every year after that**, as specified in the service letter\n\n**Why it matters:**\nFuel cells are critical components that store fuel. This directive was issued to address a specific safety concern with Goodyear BTC-39 fuel cells in these Cessna models. Airworthiness Directives are legally binding — failure to comply means the aircraft cannot legally fly in Australian airspace. This particular AD dates back to 1978, so it primarily affects historical or vintage aircraft still operating today."}},"importantCases":[],"_links":{"self":"/api/acts/ad-cessna-206-24-goodyear-fuel-cells","history":"/api/acts/ad-cessna-206-24-goodyear-fuel-cells/history","analysis":"/api/acts/ad-cessna-206-24-goodyear-fuel-cells/analysis","conflicts":"/api/acts/ad-cessna-206-24-goodyear-fuel-cells/conflicts","importantCases":"/api/acts/ad-cessna-206-24-goodyear-fuel-cells/important-cases","documents":"/api/acts/ad-cessna-206-24-goodyear-fuel-cells/documents"}}