{"id":"F2006B04958","name":"AD/CESSNA 170/27 - Fuel System Placard","slug":"ad-cessna-170-27-fuel-system-placard","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":44831,"registerId":"commonwealth-F2006B04958-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/CESSNA 170/27 - Fuel System Placard","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 170, 172, F172, FR172 and 175 Series Aeroplanes\n\n \n\nAD/CESSNA 170/27 Fuel System Placard 5/72\n\nApplicability:  All 172 and F172 series with S/Nos. 28000 to 29999, 36000 to 47746 (excluding 46000), 17247747 to 17258855 and F17200001 to F17200779 not incorporating Service Kit 172-31B or 172-32.\n\n \n\nRequirement: Action in accordance with Cessna SL SE72-7. Compliance:   Within 100 hours time in service after 31 May 1972.\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","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The text sets out a requirement limited to specified serial-number ranges and excludes aircraft that have incorporated specified service kits. The instrument does not indicate any change of scope from an earlier statement within the document itself; it defines who is covered and what must be done (Applicability; Requirement; Compliance)."},"complexity_factors":["Narrow and specific serial-number applicability ranges that require verifying aircraft records (Applicability).","Exclusion for aircraft already incorporating Service Kit 172-31B or 172-32 — requires inspection/record checks (Applicability).","Mandate references an external technical document (Cessna SL SE72-7) rather than reproducing technical detail, so implementers must obtain and follow that document (Requirement).","Deadline measured in hours time in service after a past fixed date, requiring tracking flight hours rather than a calendar deadline (Compliance).","Absence of technical detail or stated allowances for alternative compliance paths in the AD itself increases reliance on regulator or manufacturer guidance (Requirement)."],"plain_english_summary":"What this instrument does (mechanical change)\n\n- It requires certain Cessna 172 and F172 aeroplanes to have a fuel-system placard fitted. The action required is to be done exactly as set out in Cessna Service Letter SE72-7 (the AD directs “Action in accordance with Cessna SL SE72-7”) (Requirement).\n\nWho it applies to\n\n- The directive applies to specific serial-number ranges of Cessna 172 and F172 series aeroplanes: S/Ns 28000–29999, 36000–47746 (excluding 46000), 17247747–17258855 and F17200001–F17200779 (Applicability). It does not apply to aeroplanes that already incorporate Service Kit 172-31B or 172-32 (Applicability).\n\nWhen it must be done\n\n- Owners/operators must comply within 100 hours time in service after 31 May 1972 (Compliance).\n\nWhy it matters (reported purpose and practical effects)\n\n- The instrument’s stated requirement is to install a fuel-system placard as specified by the manufacturer service letter (Requirement). The instrument itself does not set out the text or design of the placard; it references the Cessna service letter for the technical content (Requirement).\n\nPractical implications, incentives and costs\n\n- Who pays: The financial and time cost of inspecting serial numbers, determining whether the applicable service kits are already installed, obtaining and fitting the placard (and any associated labour or parts) falls on the owners/operators of the affected aeroplanes (Applicability; Requirement; Compliance).\n\n- What owners must do: Owners/operators must (a) check whether their aeroplane’s serial number falls within the listed ranges, (b) confirm whether Service Kit 172-31B or 172-32 has already been incorporated (those aircraft are excluded), and (c) if applicable, follow Cessna SL SE72-7 to install the placard within the stated 100 flight-hours after 31 May 1972 (Applicability; Requirement; Compliance).\n\n- Compliance burden and timing: The deadline is expressed in flight hours after a fixed date. That creates a compliance window measured by aircraft utilisation rather than calendar days; higher-utilisation aircraft reach the deadline sooner (Compliance).\n\n- Reliance on external technical document: The AD delegates the technical detail (what the placard is and how to install it) to Cessna SL SE72-7. Implementation therefore requires access to and reliance on that service letter; the AD itself does not specify technical particulars (Requirement).\n\n- Regulatory discretion: The AD prescribes a mandatory action and a compliance deadline. The instrument itself does not record discretionary exemptions or alternative means of compliance; any variation would require reference to the regulator’s broader processes (the AD text does not set out such processes) (Requirement; Compliance).\n\nTrade-offs and risks\n\n- The directive concentrates direct costs on owners/operators of the listed serial-number aircraft that have not already incorporated the excluded service kits. The AD does not state the expected cost or labour time; those are determined by the service letter’s instructions and local labour rates (Applicability; Requirement).\n\n- Because the AD points to an external service letter for the technical solution, implementation risk includes locating the correct version of Cessna SL SE72-7 and following it accurately. The AD does not itself provide the detailed installation steps (Requirement).\n\nSource citations\n\n- Applicability: text listing affected serial-number ranges and the exclusion for Service Kit 172-31B or 172-32 (Applicability).\n- Requirement: instruction to take action in accordance with Cessna SL SE72-7 (Requirement).\n- Compliance: timing obligation “Within 100 hours time in service after 31 May 1972.” (Compliance)."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, time-bound safety directive from 1972. It has not expanded beyond its original narrow purpose of mandating a specific fuel system placard for specific Cessna aircraft models."},"complexity_factors":["Very short document (under 200 words)","Only 3 operative provisions: applicability, requirement, and compliance deadline","Single cross-reference to external document (Cessna Service Letter SE72-7)","Simple conditional logic: applies to specific serial number ranges with one exclusion (46000) and one exemption (Service Kits 172-31B/172-32)","No defined terms section — uses plain aircraft terminology","No nested exceptions or sub-delegations"],"plain_english_summary":"**What this is:** This is an Airworthiness Directive (AD) — essentially a mandatory safety notice issued by Australia's Civil Aviation Safety Authority (CASA) for specific Cessna aircraft.\n\n**What it does:** It requires owners and operators of certain Cessna 172 and F172 aeroplanes to install or update a **fuel system placard** (a warning label) in the cockpit. The specific action must follow Cessna Service Letter SE72-7.\n\n**Who it affects:** Owners and operators of Cessna 172 and F172 series aircraft with specific serial numbers:\n- Serial numbers 28000–29999\n- 36000–47746 (but **not** 46000)\n- 17247747–17258855\n- F17200001–F17200779\n\n**Exemption:** Aircraft that already have Service Kit 172-31B or 172-32 installed don't need to comply.\n\n**When it had to be done:** Within 100 hours of flying time after 31 May 1972.\n\n**Why it matters:** Fuel system placards warn pilots about critical fuel handling procedures — getting this wrong can lead to fuel starvation, engine failure, or accidents. This AD ensures pilots have clear, visible warnings about fuel system limitations or operations specific to these aircraft models."}},"importantCases":[],"_links":{"self":"/api/acts/ad-cessna-170-27-fuel-system-placard","history":"/api/acts/ad-cessna-170-27-fuel-system-placard/history","analysis":"/api/acts/ad-cessna-170-27-fuel-system-placard/analysis","conflicts":"/api/acts/ad-cessna-170-27-fuel-system-placard/conflicts","importantCases":"/api/acts/ad-cessna-170-27-fuel-system-placard/important-cases","documents":"/api/acts/ad-cessna-170-27-fuel-system-placard/documents"}}