{"id":"F2006B10254","name":"AD/GAZELLE/8 - Non Rotating Scissors Attach Bolt - Replacement","slug":"ad-gazelle-8-non-rotating-scissors-attach-bolt-replacement","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":55925,"registerId":"commonwealth-F2006B10254-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/GAZELLE/8 - Non Rotating Scissors Attach Bolt - 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 - 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n \n\n![](image.001.png)  Eurocopter SA341 and SA342 (Gazelle) Series Helicopters\n\n \n\nAD/GAZELLE/8  Non Rotating Scissors Attach Bolt - Replacement\n\n\n7/79\n\n \n\nApplicability: All models fitted with main rotor head P/N 341A.31.0001 or 341A.31.0020, all dash numbers, and not incorporating modification AMS 07.6129.\n\n \n\nDocument: Gazelle SB 01-18.\n\n \n\nCompliance: Within 100 hours time in service after 31 August 1979.\n\n \n\nBackground: The original specified torque for the non rotating scissors attach bolt has been found to be too low, and resulted in cases of excessive bolt wear. A new bolt is to be installed, and torqued to a revised figure.\n\n \n","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted safety directive addressing a specific mechanical defect in a specific aircraft type. It has not expanded beyond its original purpose of mandating a bolt replacement to prevent rotor head failures."},"complexity_factors":["Single, specific mechanical action required (bolt replacement)","Clear applicability criteria (two specific part numbers, one exclusion)","Simple compliance deadline (100 hours after fixed date)","No nested exceptions or conditional logic","Only one defined term implicitly used (P/N = Part Number)","Short document (approximately 150 words of substantive content)","Single cross-reference to manufacturer service bulletin"],"plain_english_summary":"**What this is:** This is an **Airworthiness Directive (AD)** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA). Think of it as a \"recall notice\" for aircraft, but legally binding.\n\n**What it does:** It requires owners and operators of specific **Eurocopter Gazelle helicopters** (SA341 and SA342 series) to replace a particular bolt in the main rotor head.\n\n**The problem:** The bolt that holds the \"non-rotating scissors\" (a part of the rotor assembly that stays still while the blades spin) was found to have been installed with **insufficient torque** (tightness). This caused excessive wear and potential safety risks.\n\n**Who must act:** Anyone operating a Gazelle helicopter with specific rotor head part numbers (341A.31.0001 or 341A.31.0020) that hasn't already been modified under \"AMS 07.6129\".\n\n**What they must do:**\n- Install a **new bolt** for the non-rotating scissors attachment\n- Torque it to a **revised (higher) specification**\n- Complete this work **within 100 flight hours after 31 August 1979**\n\n**Why it matters:** The main rotor head is critical to keeping the helicopter in the air. A worn or loose bolt here could lead to catastrophic rotor failure. This directive ensures a known defect is fixed before it causes an accident.\n\n**Key reference:** Operators must follow the manufacturer's Service Bulletin \"Gazelle SB 01-18\" for the correct procedure."},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The instrument implements a targeted maintenance requirement to replace and re-torque the non-rotating scissors attach bolt to remedy excessive wear caused by an originally low torque specification. The directive’s scope (specific part numbers and exclusion by modification AMS 07.6129) and required remedy (new bolt and revised torque, using Gazelle SB 01-18) align with that stated purpose (Applicability; Background; Document)."},"complexity_factors":["Narrow technical scope — applies only to helicopters with main rotor head P/N 341A.31.0001 or 341A.31.0020 and not incorporating AMS 07.6129 (Applicability).","Single clearly defined action — replace bolt and apply revised torque per Gazelle SB 01-18 (Background; Document).","Mandatory fixed compliance window — within 100 hours time in service after 31 August 1979 (Compliance).","Low regulatory discretion — directive specifies the Service Bulletin as the procedural source and gives no alternative compliance path in the text provided (Document).","Operational impact concentrated — affects only operators of the specified helicopters; imposes a maintenance scheduling and cost burden on those operators (Applicability; Compliance)."],"plain_english_summary":"This directive mandates replacing the non‑rotating scissors attach bolt on Eurocopter Gazelle helicopters fitted with main rotor head P/N 341A.31.0001 or 341A.31.0020 (unless AMS 07.6129 is installed), following Gazelle Service Bulletin 01‑18 and applying a revised torque. Operators must complete the work within 100 flight hours after 31 Aug 1979 at their own expense to prevent excessive bolt wear from the originally low torque."},"summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"The document presents the original requirements with no indication of subsequent changes."},"complexity_factors":["aviation terminology","specific part numbers and modifications","compliance deadlines"],"plain_english_summary":"This airworthiness directive was issued by the Civil Aviation Safety Authority under Part 39 of the Civil Aviation Regulations 1998. It concerns the Eurocopter SA341 and SA342 Gazelle series helicopters.\n\nThe directive requires the replacement of the non rotating scissors attach bolt. It applies to helicopters fitted with main rotor head part numbers 341A.31.0001 or 341A.31.0020 in all dash number variations. Helicopters that have incorporated modification AMS 07.6129 are exempt from this requirement.\n\nThe background indicates that the original torque specification for the bolt was too low. This led to excessive wear on the bolt. Therefore a new bolt is to be fitted and tightened using a revised torque value.\n\nThe work must be completed within 100 hours of time in service after 31 August 1979. The service bulletin Gazelle SB 01-18 provides the details for the replacement.\n\nThis is a narrow instrument that affects helicopter owners, operators and maintenance providers for the applicable Gazelle models. The practical point is to perform the bolt replacement and torque adjustment within the given compliance period to mitigate the risk of bolt wear.\n\nVisitors searching for information on Gazelle helicopter directives or maintenance tasks should determine if their aircraft matches the applicability criteria to assess relevance."}},"importantCases":[],"_links":{"self":"/api/acts/ad-gazelle-8-non-rotating-scissors-attach-bolt-replacement","history":"/api/acts/ad-gazelle-8-non-rotating-scissors-attach-bolt-replacement/history","analysis":"/api/acts/ad-gazelle-8-non-rotating-scissors-attach-bolt-replacement/analysis","conflicts":"/api/acts/ad-gazelle-8-non-rotating-scissors-attach-bolt-replacement/conflicts","importantCases":"/api/acts/ad-gazelle-8-non-rotating-scissors-attach-bolt-replacement/important-cases","documents":"/api/acts/ad-gazelle-8-non-rotating-scissors-attach-bolt-replacement/documents"}}