{"id":"F2006B04542","name":"AD/BELL 206/94 - Auxiliary Fuel System - Modification","slug":"ad-bell-206-94-auxiliary-fuel-system-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":114265,"registerId":"commonwealth-F2006B04542-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/BELL 206/94 - Auxiliary Fuel System - Modification","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\nBell Helicopter Textron Canada (BHTC) 206 and Agusta Bell 206 Series Helicopters\n\nAD/BELL 206/94 Auxiliary Fuel System \\- Modification 3/83\n\nApplicability: All models with Chadwick C-22 auxiliary fuel system installed per supplemental type certificate SH139WE.\n\nRequirement: PART 1: Install placard readily visible to the pilot in the cabin with the following annotation:-\n\nWARNING\n\n“USABLE AUX. FUEL LIMITED TO HALF AVAILABLE QTY. AT T/O”\n\nPART 2: Install Chadwick C-22-FM flow monitor kit.\n\nNote: FAA AD 82-16-12 and Chadwick SB20-81-01 refer.\n\nCompliance: PART 1: Within 10 hours time in service after 22 February, 1983.\n\nPART 2: Within 300 hours time in service, or 6 months after 31 March 1983.\n\nThe placard installed as per Part 1 above, may be removed, provided the revised flight manual supplement, Chadwick Auxiliary Fuel System C-22 dated 21 October 1981, is incorporated into the rotorcraft flight manual.\n\nBackground: Tests conducted by the auxiliary fuel system manufacturer have shown that the loss of one auxiliary tank fuel pump will result in only half the usable auxiliary fuel being available in flight. When such a failure occurs, no warning is provided.","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The directive applies only to the specified Bell 206 models fitted with the Chadwick C‑22 STC and requires two corrective measures (placard and flow monitor). The text contains no indication that the instrument expands scope beyond that original applicability or intent."},"complexity_factors":["Targeted applicability: applies only to helicopters with Chadwick C‑22 installed under STC SH139WE (Applicability).","Two distinct mandated actions: cockpit placard and installation of a flow‑monitor kit (Requirement: PART 1 & PART 2).","Conditional removal of the placard if the revised flight manual supplement is incorporated (Requirement note).","Separate, short compliance windows for each action (Compliance: PART 1 and PART 2).","Cross‑references to external documents (FAA AD 82‑16‑12 and Chadwick SB20‑81‑01) which may affect interpretation or implementation (Note).","Safety rationale based on manufacturer test data showing pump failure halves usable auxiliary fuel without warning (Background).","Operational impact on fuel planning and potential maintenance scheduling; installation costs borne by owners/operators (Requirement & Compliance)."],"plain_english_summary":"This directive requires operators of Bell/Agusta Bell 206 helicopters fitted with the Chadwick C‑22 auxiliary fuel system to install a cockpit placard limiting usable auxiliary fuel to half and to fit a Chadwick flow‑monitor kit; the placard may be removed if a revised flight‑manual supplement is incorporated. The Civil Aviation Safety Authority sets time‑based compliance windows and the costs of installation fall on aircraft owners/operators. The measure follows manufacturer tests showing loss of one auxiliary pump leaves only half the usable auxiliary fuel and gives no warning."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted safety directive addressing a specific fuel system defect. It has not expanded beyond its original purpose of mitigating fuel pump failure risks in the Chadwick C-22 system."},"complexity_factors":["Single, specific technical requirement with two distinct parts","Only 1 defined term ('time in service' implied but not explicitly defined in text)","Clear, unconditional compliance deadlines with simple alternatives","Single exception/relief provision (placard removal condition)","No cross-references to other legislation sections (only references to related FAA directive and manufacturer service bulletin for context)","Short document (approximately 200 words)","Narrow, well-defined applicability (specific helicopter models with specific aftermarket system)"],"plain_english_summary":"This mandatory airworthiness directive requires owners/operators of Bell 206-series helicopters fitted with the Chadwick C‑22 auxiliary fuel system to install a cockpit warning placard (advising only half the aux fuel is reliable for takeoff) and fit a fuel flow monitor kit. It responds to test findings that a single auxiliary pump failure can render half the fuel unusable without warning, risking fuel starvation. Operators who incorporate the specified revised flight manual may remove the placard; compliance deadlines are set for placard and kit installation."}},"importantCases":[],"_links":{"self":"/api/acts/ad-bell-206-94-auxiliary-fuel-system-modification","history":"/api/acts/ad-bell-206-94-auxiliary-fuel-system-modification/history","analysis":"/api/acts/ad-bell-206-94-auxiliary-fuel-system-modification/analysis","conflicts":"/api/acts/ad-bell-206-94-auxiliary-fuel-system-modification/conflicts","importantCases":"/api/acts/ad-bell-206-94-auxiliary-fuel-system-modification/important-cases","documents":"/api/acts/ad-bell-206-94-auxiliary-fuel-system-modification/documents"}}