{"id":"F2006B06452","name":"AD/R22/47 - Fuel Tank Vent System","slug":"ad-r22-47-fuel-tank-vent-system","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":47904,"registerId":"commonwealth-F2006B06452-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/R22/47 - Fuel Tank Vent System","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)  \nRobinson R22 Series Helicopters\n\nAD/R22/47 Fuel Tank Vent System 13/98 DM\n\nApplicability: R22 helicopters S/Nos. 0002 through 1451 except aircraft overhauled by Robinson after January 1991.\n\nRequirement: Inspect, and modify if required, the fuel tank vent system in accordance with Robinson R22 Service Bulletin No. 84.\n\nNote 1: FAA Priority Letter AD 98-21-09 also refers.\n\nNote 2: Robinson Service Bulletin No. 83 also addresses fuel tank vent system modification.\n\nCompliance: Within 25 hours time in service, or 30 days, from the effective date of this Directive, whichever occurs first.\n\nThis Airworthiness Directive becomes effective on 14 October 1998\n\nBackground: This directive is prompted by reports of uncommanded loss of engine power on R22 helicopters. The power loss events have been attributed to kinking of the fuel tank vent system.","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The directive's scope aligns with its stated safety objective: it targets a defined subset of R22 helicopters (S/N 0002–1451, excluding those overhauled by Robinson after January 1991) and mandates inspection/modification of the fuel tank vent system to address reported incidents of engine power loss attributed to vent kinking. There is no indication in the text that the scope departs from that original intent; the directive sets a narrow, time-limited requirement and references the specific service bulletin to achieve the stated mechanical change. (Applicability; Requirement; Background)"},"complexity_factors":["Targeted applicability by serial number with a specific exclusion (S/N 0002–1451; except aircraft overhauled by Robinson after January 1991) requires verification of aircraft history. (Applicability)","Mandatory action depends on an external OEM document (Robinson R22 Service Bulletin No. 84), creating dependence on external procedural material. (Requirement)","Conditional language: \"inspect, and modify if required\" means operators must first inspect and then determine whether modification is necessary, introducing an evaluative step. (Requirement)","Short compliance window (25 hours TIS or 30 days) concentrates workload and scheduling pressure on operators and maintenance providers. (Compliance)","Cross-references to additional documents (FAA AD 98-21-09; Robinson SB No. 83) require operators to consult multiple sources to understand the full technical context. (Notes)"],"plain_english_summary":"Owners/operators of Robinson R22 helicopters (S/N 0002–1451, excluding aircraft overhauled by Robinson after Jan 1991) must inspect the fuel tank vent system and, if needed, modify it per Robinson Service Bulletin No. 84. Compliance was required within 25 hours TIS or 30 days of the 14 Oct 1998 effective date. The action addresses fuel-vent kinking that can cause uncommanded engine power loss; operators will incur compliance costs."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete safety directive addressing a specific mechanical defect in a specific aircraft model. It has not expanded beyond its original purpose of mandating inspection and modification of the fuel tank vent system."},"complexity_factors":["Single, specific applicability criterion (serial number range with one exception)","Single requirement referencing an external technical document (Service Bulletin No. 84)","Simple compliance deadline (25 hours OR 30 days)","No defined terms section","No cross-references to other legislation or regulations beyond a reference to FAA directive and related service bulletin in notes","Short document (approximately 150 words)"],"plain_english_summary":"This is a **safety order** (called an \"Airworthiness Directive\") issued by Australia's aviation safety regulator for a specific type of helicopter — the **Robinson R22**.\n\n**What it does:**\nIt requires owners and operators of certain R22 helicopters to **inspect and fix the fuel tank vent system** to prevent a dangerous problem where the vent tube gets kinked (bent or pinched), which can cause the engine to suddenly lose power.\n\n**Who it affects:**\n- Owners and operators of R22 helicopters with **serial numbers 0002 through 1451**\n- **Except** helicopters that were overhauled by the manufacturer (Robinson) after January 1991\n\n**What must be done:**\n- Follow the instructions in **Robinson Service Bulletin No. 84** to check the fuel tank vent system\n- Make modifications if the inspection finds problems\n- Complete this work **within 25 flight hours or 30 days** (whichever comes first) starting from 14 October 1998\n\n**Why it matters:**\nUncommanded engine power loss means the engine cuts out unexpectedly — obviously extremely dangerous when flying. The vent system allows air to enter the fuel tank as fuel is used; if it gets kinked, a vacuum can form, starving the engine of fuel."}},"importantCases":[],"_links":{"self":"/api/acts/ad-r22-47-fuel-tank-vent-system","history":"/api/acts/ad-r22-47-fuel-tank-vent-system/history","analysis":"/api/acts/ad-r22-47-fuel-tank-vent-system/analysis","conflicts":"/api/acts/ad-r22-47-fuel-tank-vent-system/conflicts","importantCases":"/api/acts/ad-r22-47-fuel-tank-vent-system/important-cases","documents":"/api/acts/ad-r22-47-fuel-tank-vent-system/documents"}}