{"id":"F2006B08699","name":"AD/DART/12 - Control Box Mounting Bolts - Replacement","slug":"ad-dart-12-control-box-mounting-bolts-replacement","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":51876,"registerId":"commonwealth-F2006B08699-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/DART/12 - Control Box Mounting Bolts - 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 - 106 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n \n\n![](image.001.png)  Rolls Royce Turbine Engines - Dart Series\n\n \n\nAD/DART/12 Control Box Mounting Bolts - Replacement 11/87\n\nApplicability: All Dart RDa-6, RDa-7 series engines incorporating Mod. 1525. Requirement:  1. Action in accordance with Rolls Royce SB Da 76-16; or\n\n2. AD/RRT/26.\n\n \n\nEffectivity: Forthwith.\n\n \n\nBackground: Reissue of AD/RRT/26.\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 instrument is described explicitly as a reissue of AD/RRT/26 (Background) and its applicability and requirements in the provided text mirror that reissue: it applies to Dart RDa‑6 and RDa‑7 series engines with Mod. 1525 and mandates action per Rolls‑Royce SB Da 76‑16 or AD/RRT/26 (Applicability; Requirement). Based on the text supplied, there is no indication that the substantive scope of affected engines or the required compliance paths has changed from the original AD."},"complexity_factors":["Narrow technical scope limited to specific engine models and modification (Applicability)","Mandatory compliance refers to external documents (Rolls‑Royce SB Da 76‑16 or AD/RRT/26) rather than setting out procedures in the AD itself (Requirement)","Immediate effectivity ('Forthwith') increases operational scheduling pressure (Effectivity)","Reference to a prior AD (reissue of AD/RRT/26) requires cross‑checking earlier instrument to understand alternative compliance path (Background)","Technical nature of work (replacement of control box mounting bolts) requires specialist maintenance capability and parts, which can complicate implementation","No waiver, timing, or deferral provisions are included in the text provided (Requirement)"],"plain_english_summary":"If you operate a Rolls‑Royce Dart RDa‑6 or RDa‑7 engine fitted with Mod. 1525, this AD immediately requires replacement of the control‑box mounting bolts by following Rolls‑Royce Service Bulletin Da 76‑16 or the prior AD/RRT/26. It imposes an immediate maintenance obligation on owners/operators, who bear parts, labour and scheduling costs and must arrange for the technical work via their maintenance provider."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard, narrow technical airworthiness directive focused on a specific hardware replacement task. It has not expanded beyond its original safety purpose."},"complexity_factors":["Extremely short document (under 200 words)","Only 2 defined applicability criteria (engine series and modification number)","Simple binary compliance path (Option 1 OR Option 2)","No nested exceptions or conditional logic","No cross-references to other legislation beyond a single alternative directive","Immediate effectivity ('Forthwith') with no phased implementation"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** issued by Australia's Civil Aviation Safety Authority (CASA) under the Civil Aviation Regulations 1998. It mandates a safety fix for specific Rolls Royce Dart aircraft engines.\n\n**What it does:**\n- Requires owners or operators of certain Rolls Royce Dart turbine engines (RDa-6 and RDa-7 series that have Modification 1525 installed) to replace the control box mounting bolts.\n- The work must be done either by following Rolls Royce Service Bulletin Da 76-16, or by complying with a different directive called AD/RRT/26.\n\n**Who it affects:**\n- Aircraft operators and maintenance organisations using Dart RDa-6 or RDa-7 engines with Modification 1525.\n\n**Why it matters:**\n- Airworthiness Directives are legally binding safety orders. Non-compliance means the aircraft cannot fly legally. This directive addresses a specific mechanical issue with control box mounting bolts that could affect engine safety or reliability."}},"importantCases":[],"_links":{"self":"/api/acts/ad-dart-12-control-box-mounting-bolts-replacement","history":"/api/acts/ad-dart-12-control-box-mounting-bolts-replacement/history","analysis":"/api/acts/ad-dart-12-control-box-mounting-bolts-replacement/analysis","conflicts":"/api/acts/ad-dart-12-control-box-mounting-bolts-replacement/conflicts","importantCases":"/api/acts/ad-dart-12-control-box-mounting-bolts-replacement/important-cases","documents":"/api/acts/ad-dart-12-control-box-mounting-bolts-replacement/documents"}}