{"id":"F2006B04989","name":"AD/CESSNA 170/60 - Fuel Strainer Drain and Engine Muffler Tailpipe","slug":"ad-cessna-170-60-fuel-strainer-drain-and-engine-muffler-tailpipe","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":44886,"registerId":"commonwealth-F2006B04989-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/CESSNA 170/60 - Fuel Strainer Drain and Engine Muffler Tailpipe","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\n# AD/CESSNA 170/60 Fuel Strainer Drain and Engine\n\nMuffler Tailpipe\n\nApplicability: All Cessna 172R model aircraft with the following S/Ns.\n\n \n\nS/N 17280001 thru 17280016\n\n \n\nS/N 17280018 thru 17280040\n\n \n\nS/N 17280042 thru 17280054\n\n \n\nS/N 17280056 thru 17280076\n\n \n\nS/N 17280080 thru 17280081\n\n# 9/97 DM\n\n \n\nRequirement: 1. Examine the fuel strainer assy for evidence of leaks. Inspect both the fuel strainer assembly and exhaust tailpipe for evidence of chafing with the lower engine cowling. If any evidence of chafing is found carry out Requirement 2 prior to further flight.\n\n \n\n2. Modify lower engine cowl in accordance with Cessna SB97-28-01 dated June 06, 1997.\n\n \n\nNote: FAA Priority Letter AD 97-12-06 dated June 8, 1997 refers.\n\n \n\nCompliance: 1. Unless previously accomplished, comply with Requirement 1 prior to further flight and, thereafter, at each pre-flight inspection until Requirement 2 has been carried out.\n\n \n\n2. Within 10 hours time in service from the effective date of this directive. This airworthiness directive becomes effective on 16 July 1997.\n\nBackground: The manufacturer has reported that the fuel strainer drain may chafe against the lower engine cowling. This can cause the extension nut to the standpipe connection to fail resulting in fuel spillage. Standpipe failure could also result in a fire hazard or engine stoppage due to fuel loss.\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\nFederal Register of Legislative Instruments F2006B04989\n","sortOrder":0}],"analysis":{"flash_summary_failed":{"failed":true,"reason":"Unauthenticated. Configure AI_GATEWAY_API_KEY or use a provider module. Learn more: https://ai-sdk.dev/unauthenticated-ai-gateway","source":"analysis-cron"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This AD maintains its original narrow scope: addressing a specific mechanical chafing issue on a limited production run of Cessna 172R aircraft. The serial number ranges precisely target the affected fleet without expansion to other models or systems."},"complexity_factors":["Very short document (approximately 300 words)","Only 2 substantive requirements with clear sequencing","Single defined term: 'S/N' (serial number) used in obvious context","No cross-references to other legislation or complex conditional logic","Simple temporal compliance structure (immediate + 10 hours TIS)","Single external reference to Cessna Service Bulletin and FAA AD for background only"],"plain_english_summary":"This CASA Airworthiness Directive applies to certain Cessna 172R serial ranges. It warns that the fuel strainer drain (and the exhaust tailpipe) can chafe the lower engine cowling, risking fuel leaks, fire, or engine failure. Operators must inspect before further flight and complete a cowling modification per Cessna Service Bulletin within 10 flight hours. It's a mandatory safety action for owners/operators to prevent potentially catastrophic in‑flight failures."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"Scope remains focused on the originally identified risk: preventing fuel strainer/standpipe chafing against the lower engine cowling on specified Cessna 172R serial numbers by inspection and modification as described in the directive and referenced service bulletin."},"complexity_factors":["Narrow applicability — applies only to specific Cessna 172R serial numbers (lowers administrative spread).","Two-step requirement: immediate, repeated inspections (Requirement 1) and a mandated modification (Requirement 2) — adds operational urgency.","Short compliance window for modification (within 10 hours time-in-service) — increases likelihood of expedited maintenance scheduling.","Subjective inspection standard (“evidence of chafing”) — potential inspector judgment variance and enforcement ambiguity.","Technical work delegated to Cessna Service Bulletin SB97-28-01 — requires access to and reliance on an external SB for detailed instructions and likely certified maintenance.","Ongoing pre-flight inspection obligation until modification is completed — recurring compliance burden on operators.","Cross-reference to FAA Priority Letter AD 97-12-06 — introduces dependency on related foreign authority documentation for background/priority."],"plain_english_summary":"Requires owners/operators of listed Cessna 172R serial numbers to inspect the fuel strainer assembly and exhaust tailpipe for chafing against the lower engine cowling before further flight and at each pre‑flight until the cowling is modified. If chafing is found, the cowling must be modified per Cessna Service Bulletin SB97‑28‑01 within 10 flight hours to prevent fuel leakage that could cause fire or engine stoppage. Operators bear the cost and must follow the SB's technical instructions."}},"importantCases":[],"_links":{"self":"/api/acts/ad-cessna-170-60-fuel-strainer-drain-and-engine-muffler-tailpipe","history":"/api/acts/ad-cessna-170-60-fuel-strainer-drain-and-engine-muffler-tailpipe/history","analysis":"/api/acts/ad-cessna-170-60-fuel-strainer-drain-and-engine-muffler-tailpipe/analysis","conflicts":"/api/acts/ad-cessna-170-60-fuel-strainer-drain-and-engine-muffler-tailpipe/conflicts","importantCases":"/api/acts/ad-cessna-170-60-fuel-strainer-drain-and-engine-muffler-tailpipe/important-cases","documents":"/api/acts/ad-cessna-170-60-fuel-strainer-drain-and-engine-muffler-tailpipe/documents"}}