{"id":"F2006B05573","name":"AD/PA-25/37 - Goodyear Fuel Cells - Inspection","slug":"ad-pa-25-37-goodyear-fuel-cells-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":46582,"registerId":"commonwealth-F2006B05573-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/PA-25/37 - Goodyear Fuel Cells - Inspection","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)  Piper PA-25 (Pawnee) Series Aeroplanes\n\n \n\nAD/PA-25/37 Goodyear Fuel Cells - Inspection 6/78\n\nApplicability: Models PA-25, PA-25-235 and PA-25-260 with S/Nos. 25-1 to 25-7405572, fitted with Goodyear BTC-39 fuel cells.\n\n \n\nDocument: Piper SB No. 591.\n\n \n\nCompliance: Within 100 hours time in service after 30 June 1978 and thereafter annually as detailed in Piper SB No. 591.\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\n \n","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, time-bound safety directive issued in 1978 (as indicated by '6/78' in the title). It has not expanded beyond its original narrow purpose of mandating specific fuel cell inspections for a limited aircraft population. The scope remains tightly constrained to the original safety issue."},"complexity_factors":["Extremely short document (approximately 150 words)","Only 3 defined applicability criteria (aircraft models, serial number range, fuel cell type)","Single compliance requirement with clear time trigger (100 hours/annual)","No cross-references to other legislation beyond generic 'Part 39' citation","No conditional logic, exceptions, or nested provisions","Refers out to external technical document (Piper SB No. 591) for actual inspection procedures rather than including them"],"plain_english_summary":"**What this is:** This is an Airworthiness Directive (AD) — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA). Think of it like a compulsory recall notice, but for aircraft instead of cars.\n\n**What it does:** It requires owners and operators of specific Piper PA-25 \"Pawnee\" agricultural aircraft to inspect their fuel tanks (called \"fuel cells\" here) made by Goodyear. The inspection must happen within 100 hours of flying time after 30 June 1978, and then repeated every year after that.\n\n**Who it affects:** Anyone flying or maintaining Piper PA-25, PA-25-235, or PA-25-260 model aircraft with serial numbers from 25-1 up to 25-7405572 — but only if those planes have Goodyear BTC-39 fuel cells installed.\n\n**Why it matters:** Fuel cell failures can cause fuel leaks, engine failure, or fires. This AD forces a specific inspection procedure (detailed in Piper Service Bulletin 591) to catch problems before they cause accidents. Ignoring an AD is illegal — you cannot fly the aircraft until you comply.\n\n**Key details:**\n- **Compliance deadline:** Within 100 flight hours after 30 June 1978, then annually\n- **Source document:** Piper Service Bulletin No. 591 (the technical \"how-to\" guide)\n- **Regulatory basis:** Civil Aviation Regulations 1998, Part 39 (the rules that give CASA power to issue these orders)"},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The AD's scope, as stated in the source, is limited to inspection requirements for Goodyear BTC-39 fuel cells on specified Piper PA-25 models and serial numbers, with timing set to within 100 hours after 30 June 1978 and annually thereafter. The source does not indicate any widening or narrowing of that scope; it explicitly defines the affected models/serial numbers and the compliance schedule. (AD/PA-25/37; Applicability; Compliance; Document: Piper SB No. 591.)"},"complexity_factors":["Narrow applicability limited to specific models and serial-number range (reduces scope complexity). (Applicability: Models PA-25, PA-25-235 and PA-25-260 with S/Nos. 25-1 to 25-7405572.)","Mandated timing (initial inspection within a fixed number of hours after a set date, then annual repeats) is straightforward but time-sensitive. (Compliance: Within 100 hours time in service after 30 June 1978 and thereafter annually.)","Dependence on an external technical document (Piper SB No. 591) for inspection procedures introduces an extra reference that operators must obtain and follow. (Document: Piper SB No. 591.)","The AD specifies inspection obligation but does not detail remedial actions or penalties; outcomes depend on the SB and maintenance findings, creating implementation variability.","The vintage date (1978) and the serial-number span may require historical records checks to determine applicability, adding administrative effort."],"plain_english_summary":"This AD requires inspection of Goodyear BTC-39 fuel cells installed in Piper PA-25, PA-25-235 and PA-25-260 aircraft (S/N 25-1 to 25-7405572) using the procedures in Piper Service Bulletin No. 591. Inspections are due within 100 hours time-in-service after 30 June 1978 and annually thereafter; owners/operators bear inspection and repair costs to maintain airworthiness and regulatory compliance."}},"importantCases":[],"_links":{"self":"/api/acts/ad-pa-25-37-goodyear-fuel-cells-inspection","history":"/api/acts/ad-pa-25-37-goodyear-fuel-cells-inspection/history","analysis":"/api/acts/ad-pa-25-37-goodyear-fuel-cells-inspection/analysis","conflicts":"/api/acts/ad-pa-25-37-goodyear-fuel-cells-inspection/conflicts","importantCases":"/api/acts/ad-pa-25-37-goodyear-fuel-cells-inspection/important-cases","documents":"/api/acts/ad-pa-25-37-goodyear-fuel-cells-inspection/documents"}}