{"id":"F2009L04658","name":"AD/CESSNA 550/16 Amdt 1 - Fuel Flow Transmitter","slug":"ad-cessna-550-16-amdt-1-fuel-flow-transmitter","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":82554,"registerId":"commonwealth-F2009L04658-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Cessna 550 (Citation II) Series Aeroplan","sectionType":"division","heading":"Cessna 550 (Citation II) Series Aeroplanes","content":"### Cessna 550 (Citation II) Series Aeroplanes\n\n| AD/CESSNA 550/16 Amdt 1 | Fuel Flow Transmitter | 25/2009 |\n| ----------------------- | --------------------- | ------- |\n\n| Applicability: | All Citation 550/551 aircraft S/No’s 0002 to 0207 and 0209.                                                                                                                                                                                                               |\n| -------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | Replace fuel flow transmitters in accordance with Cessna Service Bulletin (SB)No. 550-73-1 Rev. 1, or later approved revision.Note 1: SB 550-73-2, or later approved revision, refers.Note 2: FAA AD 89-16-10 refers.                                                     |\n| Compliance:    | If not already accomplished, within 100 hours time in service after the effective date of this Directive.                                                                                                                                                                 |\n|                | This Amendment becomes effective on 25 March 2010.                                                                                                                                                                                                                        |\n| Background:    | The fuel flow transmitter may have an electrical connector manufactured from two pieces which may separate causing a fuel leak.This Amendment updates the revision status of the requirement SB and inserts a note referring to the applicable State of design Directive. |\n\n![](image.001.png)\n\nWilliam David  \nDelegate of the Civil Aviation Safety Authority\n\n11 December 2009","sortOrder":0},{"sectionNumber":"AD/CESSNA 550/16 Amdt 1","sectionType":"part","heading":"AD/CESSNA 550/16 Amdt 1","content":"## AD/CESSNA 550/16 Amdt 1","sortOrder":1},{"sectionNumber":"Fuel Flow Transmitter","sectionType":"part","heading":"Fuel Flow Transmitter","content":"## Fuel Flow Transmitter","sortOrder":2},{"sectionNumber":"25/2009","sectionType":"part","heading":"25/2009","content":"## 25/2009","sortOrder":3}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a narrow, technical safety directive focused on a specific aircraft part. The amendment merely updates document references without expanding the scope beyond the original fuel flow transmitter replacement requirement."},"complexity_factors":["Very short document (under 300 words)","Only 3 operative provisions: applicability, requirement, and compliance deadline","Minimal defined terms (only standard aviation abbreviations like 'SB' for Service Bulletin)","Single cross-reference to FAA directive and Cessna technical bulletin","No conditional logic or nested exceptions — straightforward 'replace this part by this date' instruction","Clear, unambiguous compliance trigger (100 hours time in service)"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — essentially a mandatory safety notice issued by Australia's aviation regulator (CASA). It applies to specific Cessna 550 and 551 business jets (serial numbers 0002 to 0207 and 0209).\n\n**What it does:**\n- Orders owners/operators to **replace faulty fuel flow transmitters** on these aircraft\n- The transmitters have a dangerous design flaw: their electrical connectors are made of two pieces that can separate and cause **fuel leaks** (obviously bad in an aircraft)\n\n**Who must act:**\n- Anyone operating the affected Cessna Citation II series aircraft\n- Must comply within **100 hours of flight time** after 25 March 2010 (unless already fixed)\n\n**Why it matters:**\nFuel leaks near hot engine components create fire and explosion risks. This directive forces a fix before catastrophe strikes. The amendment simply updates which technical document (Service Bulletin) to follow and references the original American safety directive."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The amendment updates the referenced service bulletin revision status and inserts a note referring to the State‑of‑design directive (Background/Requirement). It does not alter the aircraft applicability or the 100‑hour compliance timeframe, so the substantive scope of affected aircraft and required action remains unchanged."},"complexity_factors":["Narrow, clear applicability limited to specified serial numbers (Applicability).","Prescriptive technical action: mandatory replacement per SB No. 550‑73‑1 Rev.1 or later (Requirement) — reliance on an external service bulletin for the detailed procedure.","Short compliance window of 100 hours time in service after the effective date (Compliance) increases scheduling pressure for operators.","Reference notes to SB 550‑73‑2 and FAA AD 89‑16‑10 introduce cross‑jurisdictional references to other documents (Requirement/Notes).","Implementation burdens on owners/operators: procurement of parts, maintenance labour and aircraft downtime (implied by Requirement/Compliance).","Limited regulatory discretion: directive prescribes the action and deadline, reducing room for alternative mitigations (Directive form).","Administrative complexity from allowing 'later approved revisions' of the SB — responsibility on operator/maintainer to confirm approved revisions."],"plain_english_summary":"This directive requires replacement of the fuel flow transmitter on Cessna 550/551 aircraft S/No. 0002–0207 and 0209, to be carried out in accordance with Cessna Service Bulletin 550‑73‑1 Rev.1 (or a later approved revision) within 100 hours time‑in‑service. The change responds to a risk that a two‑piece electrical connector can separate and cause a fuel leak.\n\nAircraft owners/operators must arrange and pay for the replacement; the Civil Aviation Safety Authority issued the mandatory compliance requirement."},"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"}},"importantCases":[],"_links":{"self":"/api/acts/ad-cessna-550-16-amdt-1-fuel-flow-transmitter","history":"/api/acts/ad-cessna-550-16-amdt-1-fuel-flow-transmitter/history","analysis":"/api/acts/ad-cessna-550-16-amdt-1-fuel-flow-transmitter/analysis","conflicts":"/api/acts/ad-cessna-550-16-amdt-1-fuel-flow-transmitter/conflicts","importantCases":"/api/acts/ad-cessna-550-16-amdt-1-fuel-flow-transmitter/important-cases","documents":"/api/acts/ad-cessna-550-16-amdt-1-fuel-flow-transmitter/documents"}}