{"id":"F2006B07299","name":"AD/TB10/30 - Fuel System","slug":"ad-tb10-30-fuel-system","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":49279,"registerId":"commonwealth-F2006B07299-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/TB10/30 - Fuel 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)  \nAerospatiale (Socata) TB9 and TB10 (Tobago) Series Aeroplanes\n\nAD/TB10/30 Fuel System 12/99\n\nApplicability: Model TB9 and TB10 aeroplanes serial numbers 1 to 822, 850 to 887 and 889 to 947 equipped with an engine monitoring cluster at amendment D and having a 14 volt electrical system.\n\nNote 1: This directive is not applicable to aeroplanes with a 24 volt electrical systems.\n\nNote 2: The amendment D engine monitoring cluster is not a production fit and is only available as a spare. The amendment D cluster may be identified by markings on the engine monitoring cluster identification plate.\n\nRequirement: 1. Install a placard adjacent to the fuel indicator, in accordance with Socata Service Bulletin SB 10-099-28 dated February 1999, stating:\n\nIf voltage is lower than 13 VOLTS (below green range), fuel quantity is over-estimated.\n\n    2. Incorporate the following amendments in the Flight Manual (Pilots Operating Handbook. This may be accomplished by inserting a copy of this Directive in the Flight Manual.\n\n    In SECTION 3 ‘EMERGENCY PROCEDURES’, immediately following the ‘ALTERNATOR FAILURE’ procedure insert:\n\n![](image.002.png)\n\n    b. In SECTION 4 ‘NORMAL PROCEDURES’, in ‘PREFLIGHT INSPECTIONS’ of the ‘ELECTRICAL SYSTEMS’ procedure, at paragraph ‘a — Cabin’, insert immediately following the entry\n\n‘Fuel gages check’:\n\n![](image.003.png)\n\n    c. In SECTION 4 ‘NORMAL PROCEDURES’, in ‘AFTER STARTING ENGINE’ procedure, insert immediately before the entry\n\n‘Fuel selector set to fullest tank’:\n\n![](image.004.png)\n\nNote 3: DGAC AD 1999-062(A) refers.\n\nCOMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\nCompliance: 1. Before 31 December 1999.\n\n2. Before 31 December 1999.\n\nThis Airworthiness Directive becomes effective on 2 December 1999.\n\nBackground: This Directive is issued to ensure that pilots are aware that fuel contents may be over- estimated.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This directive maintains its original narrow scope. It addresses a specific technical safety issue (fuel gauge inaccuracy at low voltage) for a limited subset of aircraft, which aligns with the typical purpose of Airworthiness Directives."},"complexity_factors":["Short, single-purpose directive (2 requirements only)","Limited applicability defined by 3 specific criteria (serial numbers, voltage, equipment amendment)","No defined terms section or complex cross-referencing","Simple conditional logic (if voltage < 13V, then over-estimation occurs)","References only one external document (Socata Service Bulletin) and one related foreign directive (DGAC AD)","Straightforward compliance deadline (single date for all requirements)"],"plain_english_summary":"This Airworthiness Directive requires owners/operators of certain Socata TB9 and TB10 aeroplanes (specific serial ranges, 14‑volt systems, with amendment D engine monitoring) to add a cockpit warning label and update the Flight Manual to address low‑voltage fuel gauge errors.  \n\nIt matters because below about 13 volts the fuel gauge over‑reads, risking fuel starvation and engine failure; both actions were to be completed by 31 Dec 1999."},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The Directive stays within the original, narrow safety purpose: to inform pilots that fuel gauges may over‑estimate fuel when electrical voltage is low on aircraft fitted with the amendment D engine monitoring cluster and a 14 V system. It does not broaden obligations to require hardware replacement, alter airworthiness standards generally, or impose ongoing reporting duties. Therefore the scope has not grown beyond the original intent of warning pilots and prescribing a simple corrective (placard and manual insert)."},"complexity_factors":["Narrow applicability defined by model and serial number ranges (3 ranges listed).","Conditional applicability keyed to two equipment facts: amendment D engine monitoring cluster and a 14‑volt electrical system (exclusion: 24‑volt systems).","Short, prescriptive requirements: two discrete actions (placard installation; Flight Manual insert).","References to external documents: Socata Service Bulletin SB 10-099-28 and DGAC AD 1999-062(A).","Compliance deadline and effective date create a fixed time window for action.","Notes clarifying that amendment D cluster is a spare part only and identification is by markings (adds small practical identification task)."],"plain_english_summary":"**What this directive does (mechanical change):**\n\n- Requires owners/operators of certain Socata TB9 and TB10 (Tobago) aeroplanes to install a warning placard next to the fuel quantity indicator and to insert specific text pages into the aircraft Flight Manual (Pilot’s Operating Handbook).\n- The placard and manual text must follow the wording and placement instructions given by Socata Service Bulletin SB 10-099-28 (as reproduced in the Directive).\n- Compliance deadlines: both the placard and the Flight Manual inserts had to be in place by 31 December 1999; the Directive took effect on 2 December 1999. (See “Requirement” and “Compliance”.)\n\n**Which aeroplanes are affected:**\n\n- Model TB9 and TB10 aeroplanes with serial numbers 1–822, 850–887 and 889–947 that:  \n  • are fitted with an amendment D engine monitoring cluster (identifiable by markings on the cluster identification plate), and  \n  • have a 14 volt electrical system.  \n- The Directive does not apply to aeroplanes with 24 volt electrical systems. (See “Applicability” and Note 1–2.)\n\n**Why it matters (stated purpose and practical effect):**\n\n- Stated purpose: to make pilots aware that, on the affected aeroplanes with the amendment D monitoring cluster, fuel quantity indicators can over‑estimate fuel when aircraft electrical supply voltage is below about 13 volts. (See “Background” and the required placard wording.)\n- Practical effect: pilots must check electrical system voltage as part of preflight/after‑start checks, and treat fuel gauge readings as potentially unreliable when voltage is below the green range (below 13 V). That changes cockpit procedures and preflight decision points (it may lead to additional inspection or refusal to dispatch if the electrical system cannot hold voltage).\n\n**Who pays and who decides:**\n\n- Aircraft owners/operators pay for the placard and the administrative action of updating the Flight Manual (or inserting the Directive’s pages). Maintenance organisations or certificated mechanics will perform and sign off the placard installation and the manual amendment.\n- Pilots are required to follow the amended procedures and warnings during preflight and normal checks.\n\n**Costs, incentives and trade‑offs:**\n\n- Direct cost and time burden is small: producing/attaching a placard and inserting pages into the Flight Manual are routine maintenance/administrative actions.  \n- Indirect operational cost: the new checks could reduce dispatch flexibility if an aircraft’s electrical system cannot maintain voltage (operators may need to delay/abandon flights to repair the electrical system or verify fuel by other means).  \n- Alternatives open to owners: replacing the monitoring cluster, changing electrical system configuration (e.g. to 24 V where possible), or adopting stricter maintenance on the electrical system — each option has materially larger cost and downtime than the placard/manual change.  \n- Compliance risk: misidentification of the amendment D cluster or failure to install the placard/manual insert could leave pilots unaware of the inaccuracy risk. The Directive points to the Service Bulletin for placard specifics and references a related DGAC airworthiness directive (Note 3).\n\n**Implementation and enforcement mechanics:**\n\n- The Directive is prescriptive about the words and placement of the placard and the Flight Manual text inserts (so there is little regulatory discretion in how to comply).  \n- Maintenance organisations sign off compliance as part of aircraft logbooks and continuing airworthiness records.\n\n**Net operational effect:**\n\n- Small upfront compliance burden on owners/operators and maintenance providers; procedural change to pilot checks and potential for more conservative go/no‑go decisions when low voltage is detected.  \n\n(Primary source sections used: Applicability, Notes 1–3, Requirement paragraphs 1–2, Compliance, Background.)"},"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-tb10-30-fuel-system","history":"/api/acts/ad-tb10-30-fuel-system/history","analysis":"/api/acts/ad-tb10-30-fuel-system/analysis","conflicts":"/api/acts/ad-tb10-30-fuel-system/conflicts","importantCases":"/api/acts/ad-tb10-30-fuel-system/important-cases","documents":"/api/acts/ad-tb10-30-fuel-system/documents"}}