{"id":"F2006B09953","name":"AD/FK-P/8 - Slide Vane Fuel Pump","slug":"ad-fk-p-8-slide-vane-fuel-pump","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":55217,"registerId":"commonwealth-F2006B09953-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"AIRWORTHINESS DIRECTIVE","sectionType":"part","heading":"AIRWORTHINESS DIRECTIVE","content":"# AIRWORTHINESS DIRECTIVE\n\n![](image.001.png)  \n\nFor the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.1 (1) of CASR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.\n\n![](image.001.png)  \n\nFranklin Piston Engines","sortOrder":0},{"sectionNumber":"AD/FK-P/8 Slide Vane Fuel Pump 10/2003 T","sectionType":"part","heading":"AD/FK-P/8 Slide Vane Fuel Pump 10/2003 TX","content":"# AD/FK-P/8 Slide Vane Fuel Pump 10/2003 TX\n\nApplicability: All Franklin 6A-350 and 4A-235 series engines manufactured by the Franklin Engine Co., Syracuse, NY, USA fitted with a PLL-7 slide vane pump.\n\nNote 1: This pump may have been fitted as a replacement to the diaphragm pump as detailed in AD/FK-P/6 Amdt 1.\n\nRequirement: Check for correct mating of the fuel pump drive gears and carry out any subsequent rectification in accordance with WSK PZL Service Bulletin PZL-F/75/2003.\n\nNote 2: Republic of Poland General Inspectorate of Civil Aviation Airworthiness Directive Nr SP-0048-2003-B refers.\n\nCompliance: Before further flight.\n\nThis Airworthiness Directive becomes effective on 22 August 2003.\n\nBackground: The fuel pump drive gear fitted to Franklin engines manufactured in the USA may have a different diametral pitch to the PLL-7 fuel pump gear. Different diametral pitch of the fuel pump drive gears can lead to abnormal wear and premature failure of the engine driven fuel pump.\n\n![](image.002.png)  \n\nJim Coyne\n\nDelegate of the Civil Aviation Safety Authority 20 August 2003\n\n![](image.001.png)","sortOrder":1}],"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 incompatibility between specific engine models and a specific fuel pump. There is no evidence of scope creep; it targets exactly the safety issue identified in the background (gear pitch mismatch) without expanding to unrelated systems or broader engine families."},"complexity_factors":["Very short document (approximately 250 words)","Only 2 defined applicability criteria (engine series and pump model)","Single requirement with clear cross-reference to manufacturer service bulletin","No nested exceptions or conditional logic","Simple compliance deadline (immediate/before further flight)","Minimal legislative cross-referencing (only CASR 1998 subregulation 39.1(1) mentioned in preamble)"],"plain_english_summary":"This AD mandates immediate, before‑flight inspection of PLL‑7 slide‑vane fuel pumps installed on Franklin 6A‑350 and 4A‑235 series engines because mismatched pump drive gears (different diametral pitch) can wear rapidly and cause in‑flight fuel pump failure.  \n\nOperators must verify gear mesh and correct defects per the pump manufacturer’s service instructions to prevent engine stoppage. The directive took effect 22 August 2003."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The AD explicitly defines its applicability as all Franklin 6A-350 and 4A-235 series engines fitted with a PLL-7 slide vane pump (Applicability). It notes that the pump may have been fitted as a replacement (Note 1) but does not otherwise expand or narrow the scope within the instrument's text."},"complexity_factors":["Technical specificity: inspection focuses on gear mating and diametral pitch, requiring mechanical assessment and possible parts replacement or repair (Background; Requirement).","Immediate compliance: corrective action must be done 'Before further flight', increasing operational disruption and scheduling pressure (Compliance).","External dependencies: rectification must follow WSK PZL Service Bulletin PZL-F/75/2003, so access to and reliance on that bulletin is necessary (Requirement).","Applicability nuance: limited to Franklin 6A-350 and 4A-235 engines with a PLL-7 pump, but Note 1 flags that pumps may have been retrofitted as replacements, creating inspection scope uncertainty (Applicability; Note 1).","Cross-references: the AD refers to a prior AD and a Republic of Poland airworthiness directive, requiring practitioners to consult multiple instruments (Note 1; Note 2).","Regulatory source: issued under CASR subregulation 39.1(1) by a CASA delegate, establishing legal enforceability and administrative authority (introductory paragraph; signature)."],"plain_english_summary":"This AD requires inspection and, if necessary, correction of the fuel pump drive gear mating on Franklin 6A-350 and 4A-235 engines fitted with a PLL-7 slide vane pump, using WSK PZL Service Bulletin PZL-F/75/2003, and completed before further flight. It affects owners, operators and maintenance organisations because mismatched gear diametral pitch can cause abnormal wear and premature fuel pump failure (Background)."}},"importantCases":[],"_links":{"self":"/api/acts/ad-fk-p-8-slide-vane-fuel-pump","history":"/api/acts/ad-fk-p-8-slide-vane-fuel-pump/history","analysis":"/api/acts/ad-fk-p-8-slide-vane-fuel-pump/analysis","conflicts":"/api/acts/ad-fk-p-8-slide-vane-fuel-pump/conflicts","importantCases":"/api/acts/ad-fk-p-8-slide-vane-fuel-pump/important-cases","documents":"/api/acts/ad-fk-p-8-slide-vane-fuel-pump/documents"}}