{"id":"F2006B05510","name":"AD/PA-23/83 - Heater Fuel Regulator Valve Shroud - Drain Modification","slug":"ad-pa-23-83-heater-fuel-regulator-valve-shroud-drain-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":46365,"registerId":"commonwealth-F2006B05510-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/PA-23/83 - Heater Fuel Regulator Valve Shroud - Drain Modification","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-23 (Apache and Aztec) Series Aeroplanes\n\n \n\nAD/PA-23/83 Heater Fuel Regulator Valve Shroud - Drain Modification\n\n\n7/82\n\n \n\nApplicability: All models PA-23-250 with S/Nos. 27-3050, 27-3154 to 27-8154015 with Janitrol heater installation.\n\n \n\nDocument: Piper SB No. 721.\n\n \n\nCompliance: Within 100 hours time in service after 31 July, 1982.\n\n \n\nBackground:  The manufacturer has received a field report of a heater fuel regulator valve leaking fuel into the fuselage nose compartment.\n\n \n","sortOrder":0}],"analysis":{"kimi_summary":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":2046},"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This appears to be the original directive establishing the mandatory modification requirement."},"complexity_factors":["Single technical requirement referencing external manufacturer service bulletin (Piper SB No. 721)","Narrow applicability limited to specific aircraft serial number ranges and specific equipment (Janitrol heater)","Simple conditional compliance deadline (100 hours time-in-service after fixed calendar date)","No nested exceptions or defined terms section"],"plain_english_summary":"This mandatory Airworthiness Directive requires owners/operators of certain Piper PA-23-250 (specific serials) equipped with a Janitrol cabin heater to install a drain modification on the heater fuel‑regulator shroud per Piper Service Bulletin No. 721. The fix must be done within 100 flight hours after July 31, 1982. It prevents fuel leaking into the nose compartment — a fire/explosion hazard — and is required to keep the aircraft airworthy."}},"importantCases":[],"_links":{"self":"/api/acts/ad-pa-23-83-heater-fuel-regulator-valve-shroud-drain-modification","history":"/api/acts/ad-pa-23-83-heater-fuel-regulator-valve-shroud-drain-modification/history","analysis":"/api/acts/ad-pa-23-83-heater-fuel-regulator-valve-shroud-drain-modification/analysis","conflicts":"/api/acts/ad-pa-23-83-heater-fuel-regulator-valve-shroud-drain-modification/conflicts","importantCases":"/api/acts/ad-pa-23-83-heater-fuel-regulator-valve-shroud-drain-modification/important-cases","documents":"/api/acts/ad-pa-23-83-heater-fuel-regulator-valve-shroud-drain-modification/documents"}}