{"id":"F2006B05739","name":"AD/PA-31/35 - Heater Fuel Manual Shut-Off Valve - Removal","slug":"ad-pa-31-35-heater-fuel-manual-shut-off-valve-removal","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":135557,"registerId":"commonwealth-F2006B05739-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/PA-31/35 - Heater Fuel Manual Shut-Off Valve - Removal","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-31 Series Aeroplanes\n\n \n\nAD/PA-31/35 Heater Fuel Manual Shut-Off Valve - Removal 2/75\n\nApplicability: Models PA-31 and PA-31-300 with S/Nos. 31-2 to 31-7401258. Document:  Piper SB No. 417.\n\nCompliance: Within 100 hours time in service after 28 February 1975.\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\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 1975 (as indicated by '2/75' in the title). It addresses a specific technical defect in a specific aircraft model. There is no evidence of scope creep; it remains precisely targeted at the original safety issue."},"complexity_factors":["Extremely short document (under 150 words)","Only 4 operative provisions: applicability, reference document, action required, and compliance deadline","No defined terms section","No cross-references to other legislation beyond the parent Civil Aviation Regulations 1998","Single unconditional requirement with straightforward temporal compliance trigger","No exceptions, exemptions, or conditional logic"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA). It applies to specific **Piper PA-31 aircraft** (models PA-31 and PA-31-300 with serial numbers 31-2 through 31-7401258).\n\n**What it requires:**\n- **Remove the manual shut-off valve** from the heater fuel system\n- **Follow the procedure** in Piper Service Bulletin No. 417\n\n**Why it matters:**\nAirworthiness Directives are legally binding safety instructions. If you own or operate one of these aircraft, you **must** complete this modification within 100 hours of flying time after 28 February 1975. Non-compliance means the aircraft cannot legally fly.\n\nThis particular AD addresses a safety defect in the heater fuel system that required the removal of a manual valve — likely due to fire risk, fuel leakage, or operational safety concerns identified by the manufacturer."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The supplied text sets out a single, targeted action (removal of the heater fuel manual shut-off valve) for a defined set of PA-31 series serial numbers and refers to Piper SB No. 417 for the procedure. The document does not provide any information about an earlier or different scope from which this directive was altered, so there is no evidence in the supplied text that the scope has changed from an original intent."},"complexity_factors":["Narrow and specific applicability (particular models and a defined serial-number range) reduces scope complexity. (See: \"Applicability\".)","Single, discrete mandated action (removal of a single component) simplifies technical complexity. (See: AD title and compliance requirement.)","Mandatory compliance deadline (100 hours TIS after a specific date) produces scheduling and enforcement complexity for operators. (See: \"Compliance\".)","Dependence on an external document (Piper Service Bulletin No. 417) for technical instructions increases procedural reliance on the manufacturer. (See: \"Document: Piper SB No. 417\".)","Lack of detailed rationale or instructions within the AD text increases interpretation risk until the service bulletin is consulted. (See: full AD text provided.)"],"plain_english_summary":"This CASA airworthiness directive mandates removal of the heater fuel manual shut‑off valve from specified Piper PA‑31 and PA‑31‑300 aeroplanes (serials 31‑2 through 31‑7401258), to be done per Piper Service Bulletin No. 417 within 100 hours TIS after 28 February 1975.\n\nAffected owners/operators must arrange and pay for the removal; the AD points to the manufacturer's SB for the technical justification and work instructions."}},"importantCases":[],"_links":{"self":"/api/acts/ad-pa-31-35-heater-fuel-manual-shut-off-valve-removal","history":"/api/acts/ad-pa-31-35-heater-fuel-manual-shut-off-valve-removal/history","analysis":"/api/acts/ad-pa-31-35-heater-fuel-manual-shut-off-valve-removal/analysis","conflicts":"/api/acts/ad-pa-31-35-heater-fuel-manual-shut-off-valve-removal/conflicts","importantCases":"/api/acts/ad-pa-31-35-heater-fuel-manual-shut-off-valve-removal/important-cases","documents":"/api/acts/ad-pa-31-35-heater-fuel-manual-shut-off-valve-removal/documents"}}