{"id":"F2006B03633","name":"AD/BEECH 1900/15 - Engine Fuel Filter Bypass Valve","slug":"ad-beech-1900-15-engine-fuel-filter-bypass-valve","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":43223,"registerId":"commonwealth-F2006B03633-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/BEECH 1900/15 - Engine Fuel Filter Bypass Valve","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nBeechcraft 1900 Series Aeroplanes\n\nAD/BEECH 1900/15 Engine Fuel Filter Bypass Valve 2/97\n\nApplicability: Beech 1900C aircraft serial numbers UC-1 through UC-174 and Beech 1900D aircraft serial numbers UE-1 through UE-205.\n\nRequirement: To prevent contamination of the engine fuel filter bypass valve resulting in a possible engine shutdown, inspect the engine fuel filter bypass valve in accordance with the requirements of Raytheon Aircraft Mandatory Service Bulletin Number 2678.\n\nNote: FAA Airworthiness Directive 96-22-12 refers.\n\nCompliance: Effective 30 January 1997: Unless previously accomplished; within 50 hours time in service.\n\nBackground: This directive has been issued to require certain engine fuel filter bypass valves to be inspected for evidence of contamination. The requirement follows reports of fuel filter bypass valves being contaminated by thread lock adhesive residue.\n\nContamination of the filter bypass valve will not be apparent in service until the filter element becomes clogged, for whatever reason, and failure of the filter bypass valve to open results in a fuel flow interruption and loss of engine power.\n\nFederal Register of Legislative Instruments F2006B03633","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted safety directive addressing a specific mechanical defect in specific aircraft. It has not expanded beyond its original purpose of preventing engine fuel starvation due to contaminated bypass valves."},"complexity_factors":["Single, specific mechanical component targeted (fuel filter bypass valve)","Clear applicability criteria (specific aircraft models and serial number ranges)","Single compliance action required (inspection per manufacturer bulletin)","No defined terms section or interpretive provisions","No nested exceptions or conditional logic — straightforward 'inspect by X date or hours' requirement","Short document (under 300 words), minimal cross-referencing (only one FAA directive noted)"],"plain_english_summary":"This CASA Airworthiness Directive requires owners/operators of specified Beechcraft 1900C (UC‑1 to UC‑174) and 1900D (UE‑1 to UE‑205) aircraft to perform a one‑time inspection of the engine fuel filter bypass valve per the Raytheon service bulletin, within 50 flight hours if not already done. \n\nIt addresses a safety risk from thread‑lock adhesive contaminating the valve and jamming it closed, which could cause engine fuel starvation and in‑flight shutdown; it aligns with the FAA action."},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The directive's scope is confined to the listed Beech 1900C/D serial numbers and mandates inspection per Raytheon SB 2678 within the stated 50-hour window. There is no addition or narrowing of affected aircraft or actions beyond the Applicability and Requirement stated in the instrument."},"complexity_factors":["Narrow applicability: specific serial-number ranges (Applicability).","Single technical action: inspection per a named service bulletin (Requirement).","Short, fixed compliance window: within 50 hours from a set date (Compliance).","Dependence on an external document for procedural detail: Raytheon Service Bulletin 2678 (Requirement).","Safety-critical consequence if ignored (Background).","Low regulatory discretion: directive specifies what must be done and when."],"plain_english_summary":"**What this does:** This airworthiness directive requires owners/operators of specified Beech 1900C/D aeroplanes (serials UC-1–UC-174, UE-1–UE-205) to inspect the engine fuel filter bypass valve following Raytheon Mandatory Service Bulletin No. 2678 to guard against contamination that can cause engine shutdown (Applicability; Requirement; Background).\n\n**Who acts and when:** Compliance was required within 50 hours time-in-service from 30 January 1997; affected operators must arrange the inspection and any corrective work (Compliance; Requirement)."}},"importantCases":[],"_links":{"self":"/api/acts/ad-beech-1900-15-engine-fuel-filter-bypass-valve","history":"/api/acts/ad-beech-1900-15-engine-fuel-filter-bypass-valve/history","analysis":"/api/acts/ad-beech-1900-15-engine-fuel-filter-bypass-valve/analysis","conflicts":"/api/acts/ad-beech-1900-15-engine-fuel-filter-bypass-valve/conflicts","importantCases":"/api/acts/ad-beech-1900-15-engine-fuel-filter-bypass-valve/important-cases","documents":"/api/acts/ad-beech-1900-15-engine-fuel-filter-bypass-valve/documents"}}