{"id":"F2006B11336","name":"AD/MSR/9 - Fuel System - Fuel Gauge Ball - Replacement","slug":"ad-msr-9-fuel-system-fuel-gauge-ball-replacement","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":57217,"registerId":"commonwealth-F2006B11336-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/MSR/9 - Fuel System - Fuel Gauge Ball - Replacement","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)  Aerospatiale Rallye Series Aeroplanes\n\n \n\nAD/MSR/9 Fuel System - Fuel Gauge Ball - Replacement 11/64\n\nApplicability: All MS880, MS885 and MS890 series with S/Nos. 5001 to 5204. Document:  1. Rallye SB No. 26; or\n\n2. Bureau Veritas Airworthiness Spec. 64-8-8. Compliance: Forthwith.\n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, single-issue safety directive focused specifically on fuel gauge ball replacement in a limited aircraft population. It has not expanded beyond its original narrow technical purpose."},"complexity_factors":["Extremely short document (approximately 150 words)","Only 3 defined applicability criteria (aircraft models and serial numbers)","Single, unambiguous compliance action (replacement of one component)","No nested exceptions or conditional logic","No cross-references to other legislation beyond two alternative technical documents","Clear imperative language ('Forthwith') with no temporal ambiguity"],"plain_english_summary":"**What this is:** This is an **Airworthiness Directive (AD)** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA). Think of it as a \"recall notice\" for aircraft, but legally binding.\n\n**What it requires:** Owners and operators of specific **Aerospatiale Rallye series aeroplanes** (models MS880, MS885, and MS890 with serial numbers 5001 to 5204) must **replace the fuel gauge ball** in their aircraft's fuel system. The \"fuel gauge ball\" is a floating component inside the fuel tank that indicates fuel levels to the pilot.\n\n**Who must comply:** Anyone who owns or operates the affected aircraft models within the specified serial number range.\n\n**When:** **\"Forthwith\"** — meaning immediately, without delay. This is urgent safety-critical maintenance.\n\n**Why it matters:** Faulty fuel gauge balls can give pilots incorrect readings about how much fuel remains. Running out of fuel unexpectedly is obviously catastrophic. This directive ensures the defective part is replaced before it can cause an accident.\n\n**How to comply:** Follow either:\n- **Rallye Service Bulletin No. 26** (the manufacturer's official repair instructions), OR\n- **Bureau Veritas Airworthiness Specification 64-8-8** (an alternative approved technical standard)\n\n**The bottom line:** If you fly or maintain one of these specific Rallye aircraft, you cannot legally operate it until you've replaced this fuel gauge component according to the specified technical documents."},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The directive applies only to the stated Aerospatiale Rallye MS880, MS885 and MS890 aircraft with serial numbers 5001–5204 and mandates immediate replacement of the fuel gauge ball following one of two specified documents (Applicability; Document; Compliance). The instrument does not expand or narrow that set of affected aircraft or add additional obligations beyond the single mandated action, so there is no change in scope from the stated applicability and required action."},"complexity_factors":["Narrow applicability limited to specific models and serial numbers (Applicability)","Single clear mandated action (replacement of the fuel gauge ball)","Compliance timing is immediate and unqualified (Compliance: 'Forthwith')","Specific reference to one of two technical documents reduces procedural ambiguity (Document)","No multi-step compliance regime, no phased requirements, and no conditional exemptions in the text provided"],"plain_english_summary":"This AD mandates immediate replacement of the fuel‑gauge ball on Aerospatiale Rallye MS880, MS885 and MS890 aeroplanes serial numbers 5001–5204, to be done per Rallye SB No. 26 or Bureau Veritas Airworthiness Spec. 64‑8‑8. It legally binds owners/operators (who bear parts, labour and downtime costs) and maintenance suppliers to perform the safety‑critical work without discretion. Compliance is required forthwith."}},"importantCases":[],"_links":{"self":"/api/acts/ad-msr-9-fuel-system-fuel-gauge-ball-replacement","history":"/api/acts/ad-msr-9-fuel-system-fuel-gauge-ball-replacement/history","analysis":"/api/acts/ad-msr-9-fuel-system-fuel-gauge-ball-replacement/analysis","conflicts":"/api/acts/ad-msr-9-fuel-system-fuel-gauge-ball-replacement/conflicts","importantCases":"/api/acts/ad-msr-9-fuel-system-fuel-gauge-ball-replacement/important-cases","documents":"/api/acts/ad-msr-9-fuel-system-fuel-gauge-ball-replacement/documents"}}