{"id":"F2006B02583","name":"AD/B-2/12 - Main Transmission Forward Mount - Rework","slug":"ad-b-2-12-main-transmission-forward-mount-rework","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":41839,"registerId":"commonwealth-F2006B02583-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/B-2/12 - Main Transmission Forward Mount - Rework","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)  Brantly B-2 Series Helicopters\n\n \n\nAD/B-2/12 Main Transmission Forward Mount - Rework 3/61\n\nApplicability: All model B-2 as listed in SB No. 9. Document: Brantly SB No. 9.\n\nCompliance: 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\n \n\n \n","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The document applies to \"All model B-2 as listed in SB No. 9\" and mandates rework per Brantly SB No. 9 with compliance required \"Forthwith.\" The text contains no indication that the applicability or required action differs from what is stated, so there is no evidence in this source that the scope has been changed from the stated applicability."},"complexity_factors":["Short, single-action directive (rework) with clear applicability reduces legal complexity.","Immediate compliance term ('Forthwith') increases operational urgency despite procedural simplicity.","Technical details are delegated to an external document (Brantly SB No. 9), requiring users to obtain and interpret that service bulletin.","AD does not specify costs, scheduling mechanisms, or discretionary relief, creating practical uncertainty for operators.","The issuance context (CASA Airworthiness Directive) is formal but the text provided lacks enforcement, reporting, or follow-up measures."],"plain_english_summary":"### What this instrument does (mechanical change)\n\nThis is an Airworthiness Directive issued under the Civil Aviation Regulations (Part 39). It requires that the main transmission forward mount on Brantly B-2 series helicopters be reworked in accordance with Brantly Service Bulletin No. 9. (See: \"Document: Brantly SB No. 9\" and \"Applicability: All model B-2 as listed in SB No. 9\".)\n\n### Who issues it and who it affects\n\n- Issuer: Civil Aviation Safety Authority (CASA) — indicated by the document header.  \n- Affected parties: owners and operators of Brantly B-2 helicopters that are listed in Brantly SB No. 9, and any maintenance organisations or personnel who perform the rework. (See: \"Applicability\" and \"Document\".)\n\n### How and when it must be complied with\n\n- The directive requires compliance \"Forthwith.\" That means the rework called for by SB No. 9 must be carried out without delay. (See: \"Compliance: Forthwith.\")\n\n### What the document does not specify (concrete gaps you should note)\n\n- The AD itself references Brantly SB No. 9 for the technical instructions, but the AD does not include the technical steps; operators must obtain and follow SB No. 9. (See: \"Document: Brantly SB No. 9.\")\n- The AD does not state who pays for the rework, who must schedule it, or whether CASA will provide exemptions or phased compliance. (No text in the AD allocates costs or grants discretion.)\n- The AD does not state inspection intervals, acceptability criteria, or post-rework reporting requirements; those details (if any) would be found in SB No. 9 or other CASA guidance. (Absence noted against the AD text.)\n\n### Incentives, costs and implementation mechanics (source-grounded)\n\n- Who pays: not stated in the AD. Operators should expect they will need to arrange and fund the rework unless another arrangement is provided elsewhere. (See: AD text: no cost allocation.)\n- Who decides operationally: CASA issued the AD; operational decisions (timing, selection of maintenance provider, recordkeeping) rest with the aircraft owner/operator subject to the requirement to comply \"forthwith.\" (See: CASA header; \"Compliance: Forthwith.\")\n- Compliance burden: immediate action is required and the AD defers to the service bulletin for technical execution. This creates a need to obtain SB No. 9, plan downtime, and allocate maintenance resources promptly. (See: \"Document: Brantly SB No. 9\" and \"Compliance: Forthwith.\")\n- Bureaucratic discretion: the AD as presented does not specify any discretionary relief, phased approaches, or cost-sharing; any such measures would need to be provided in other CASA instruments or correspondence. (Absence noted in the AD.)\n\n### Practical takeaways for an operator\n\n- If you operate a Brantly B-2 listed in SB No. 9, obtain Brantly SB No. 9 immediately and arrange for the forward main transmission mount to be reworked without delay. (See: \"Applicability\" and \"Compliance: Forthwith.\")\n- Expect to engage a maintenance organisation and to bear the operational and financial impacts unless informed otherwise by CASA or the aircraft manufacturer. The AD does not itself set out cost, scheduling, or enforcement detail beyond requiring compliance.\n\n(References: Applicability; Document; Compliance: Forthwith.)"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard, narrow airworthiness directive focused on a specific mechanical defect in a specific aircraft type. It has not expanded beyond its original safety-critical purpose."},"complexity_factors":["Extremely short document (under 200 words)","Only 1 defined term implicitly referenced (SB No. 9)","No cross-references to other legislation beyond the parent Civil Aviation Regulations 1998","Simple unconditional command structure: applicability + document reference + compliance deadline","No exceptions, exemptions, or conditional logic","Single operational requirement with immediate effect"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** issued by Australia's Civil Aviation Safety Authority (CASA) for **Brantly B-2 series helicopters**.\n\n**What it does:**\n- Requires owners and operators of these helicopters to perform a **rework** (repair or modification) on the **main transmission forward mount** — a critical structural component that holds the main gearbox in place.\n- The work must follow **Service Bulletin No. 9** issued by the manufacturer (Brantly).\n\n**Who it affects:**\n- Anyone who owns or operates a **Brantly B-2 helicopter** (all models listed in the referenced service bulletin).\n\n**Why it matters:**\n- The main transmission mount is essential for flight safety. If it fails, the main rotor system could detach or malfunction, leading to catastrophic loss of control.\n- The directive uses the word **\"Forthwith\"** — meaning the repair must be done **immediately**, before further flight. This indicates CASA has identified an urgent safety risk.\n\n**Key takeaway:** If you fly or maintain a Brantly B-2, you cannot legally operate it until this structural repair is completed according to the manufacturer's instructions."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b-2-12-main-transmission-forward-mount-rework","history":"/api/acts/ad-b-2-12-main-transmission-forward-mount-rework/history","analysis":"/api/acts/ad-b-2-12-main-transmission-forward-mount-rework/analysis","conflicts":"/api/acts/ad-b-2-12-main-transmission-forward-mount-rework/conflicts","importantCases":"/api/acts/ad-b-2-12-main-transmission-forward-mount-rework/important-cases","documents":"/api/acts/ad-b-2-12-main-transmission-forward-mount-rework/documents"}}