{"id":"F2006B04746","name":"AD/BN-2/34 - Rudder Bar Lower Mounting - Inspection and Modification","slug":"ad-bn-2-34-rudder-bar-lower-mounting-inspection-and-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":44510,"registerId":"commonwealth-F2006B04746-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/BN-2/34 - Rudder Bar Lower Mounting - Inspection and Modification","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)  Pilatus Britten-Norman BN-2 Series Aeroplanes\n\n \n\nAD/BN-2/34 Rudder Bar Lower Mounting - Inspection NK\n\nand Modification\n\n \n\nApplicability: All model BN-2A which have exceeded 1000 hours total time in service, except those which have incorporated Mod. No. NB/M/463 Part A.\n\n \n\nDocument: Britten Norman SB No. BN-2/SB.74, Issue 2.\n\n \n\nCompliance: Within 25 hours time in service after 24 May 1976 and thereafter at intervals not exceeding 200 hours time in service until modified. Modify not later than 31 August 1976.\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, time-bound safety directive issued under Part 39 of the Civil Aviation Regulations 1988. It addresses a specific mechanical defect in a specific aircraft type. There is no indication of scope creep; the directive remains tightly focused on the rudder bar mounting issue as originally identified."},"complexity_factors":["Single, clearly defined applicability clause (one aircraft model, one hour threshold, one exemption)","Straightforward compliance timeline (initial inspection + recurring intervals + hard deadline for modification)","No defined terms section — uses plain aviation terminology","Single cross-reference to manufacturer service bulletin","No nested conditions or exceptions beyond the standard exemption clause","Extremely short document (approximately 150 words of substantive content)"],"plain_english_summary":"This is an **Airworthiness Directive** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA). It applies to a specific type of aircraft: the **Pilatus Britten-Norman BN-2 series** (commonly known as the Islander).\n\n**What it requires:**\n- **Who must comply:** Owners or operators of BN-2A model aircraft that have flown more than 1,000 hours, unless they've already made a specific factory modification (Mod. No. NB/M/463 Part A).\n- **What must be done:** Inspect the **rudder bar lower mounting** — that's a structural part connecting the pilot's foot pedals to the rudder system. The inspection checks for cracks or wear that could affect steering control.\n- **When:** First inspection within 25 flight hours after 24 May 1976, then every 200 flight hours until a permanent fix is installed.\n- **Permanent fix:** Modify the aircraft (as described in the manufacturer's Service Bulletin BN-2/SB.74) no later than 31 August 1976.\n\n**Why it matters:** A failed rudder bar mounting could cause loss of directional control during flight or landing — a serious safety risk. This directive forces operators to catch problems early through repeated inspections and ultimately fix them permanently."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The document itself sets a clear applicability and compliance regime and contains no internal indication that its scope has been altered from the stated applicability. It applies to BN-2A aircraft with more than 1,000 hours total time in service except those with Mod. No. NB/M/463 Part A, references Service Bulletin BN-2/SB.74 Issue 2 for work instructions, imposes an initial inspection and recurring inspections until modification, and sets a mandatory modification date of 31 August 1976. (Applicability; Document; Compliance)"},"complexity_factors":["Technical subject matter (airframe component) requiring maintenance skills and parts.","Time-based compliance schedule with a short initial window (25 hours) and recurring 200-hour inspections until modification.","A fixed cut-off date for mandatory modification (31 August 1976).","Cross-reference to an external Service Bulletin (BN-2/SB.74 Issue 2) for procedural detail rather than including procedures in the AD text.","Applicability exception tied to prior incorporation of a specific modification (Mod. No. NB/M/463 Part A).","Operational scheduling and availability constraints for operators and maintenance providers created by the deadlines."],"plain_english_summary":"This Airworthiness Directive requires inspection and modification of the rudder bar lower mounting on Pilatus Britten‑Norman BN‑2A aeroplanes that have exceeded 1,000 hours service (except those with Mod. No. NB/M/463 Part A). Operators must inspect within 25 hours after 24 May 1976 and every 200 hours until the modification is done, with the modification completed by 31 August 1976. It imposes compliance, cost and downtime on aircraft owners/operators."}},"importantCases":[],"_links":{"self":"/api/acts/ad-bn-2-34-rudder-bar-lower-mounting-inspection-and-modification","history":"/api/acts/ad-bn-2-34-rudder-bar-lower-mounting-inspection-and-modification/history","analysis":"/api/acts/ad-bn-2-34-rudder-bar-lower-mounting-inspection-and-modification/analysis","conflicts":"/api/acts/ad-bn-2-34-rudder-bar-lower-mounting-inspection-and-modification/conflicts","importantCases":"/api/acts/ad-bn-2-34-rudder-bar-lower-mounting-inspection-and-modification/important-cases","documents":"/api/acts/ad-bn-2-34-rudder-bar-lower-mounting-inspection-and-modification/documents"}}