{"id":"F2006B07100","name":"AD/S-PUMA/23 - Main Rotor Spindles and Flapping Hinge Pins","slug":"ad-s-puma-23-main-rotor-spindles-and-flapping-hinge-pins","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":48878,"registerId":"commonwealth-F2006B07100-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/S-PUMA/23 - Main Rotor Spindles and Flapping Hinge Pins","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)  \nEurocopter AS 332 (Super Puma) Series Helicopters\n\nAD/S-PUMA/23 Main Rotor Spindles and Flapping Hinge Pins 9/96\n\nApplicability: Models C, C1, L, and L1 not modified per MOD. 07-43100; and fitted with spindles P/N 332A31-1390-00 to -07, 332A31-1398-00; and all dash number flapping hinge pins P/N 332A31-1380-.\n\nRequirement: Action in accordance with Eurocopter AS332 SB No. 01.00.44.\n\nNote: DGAC AD 96-100-058(B) refers.\n\nCompliance: In accordance with Paragraph 1.D of the Requirement document, with effect from 15 August 1996.\n\nBackground: Tests by the manufacturer have discovered that ageing has modified the static and dynamic properties of the frequency adapters, leading to the introduction of considerable loads which reduce the life limits of the spindles and flapping hinge pins. This Directive is to remove from service those spindles and pins that have not been reinforced to cope with the increased loads.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This Airworthiness Directive maintains its original narrow scope — addressing a specific safety-critical fatigue issue in defined helicopter models. It has not expanded beyond its original purpose of mandating replacement of specific aging rotor components."},"complexity_factors":["Single, specific technical requirement referencing an external document (Eurocopter SB No. 01.00.44)","Limited applicability criteria using precise part numbers and model designations","No nested conditional logic or exceptions within the directive itself","Short length (approximately 150 words of substantive content)","Only 4 defined technical terms requiring cross-reference (MOD number, P/N ranges, SB reference, DGAC AD reference)","Clear compliance date and straightforward background explanation"],"plain_english_summary":"This is an **Airworthiness Directive** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) that requires specific maintenance action on certain helicopters.\n\n**What it does:**\nOrders owners and operators of specific Eurocopter AS 332 \"Super Puma\" helicopters to inspect and replace certain main rotor spindles and flapping hinge pins before they fail.\n\n**Who it affects:**\n- Owners and operators of Eurocopter AS 332 models C, C1, L, and L1 helicopters\n- Specifically those that have **not** been modified according to MOD. 07-43100\n- Only helicopters with specific part numbers for spindles (P/N 332A31-1390-00 through -07, and 332A31-1398-00) and any dash number of flapping hinge pins (P/N 332A31-1380-)\n\n**Why it matters:**\nThe manufacturer discovered that as these parts age, their vibration-dampening \"frequency adapters\" degrade. This causes dangerous stress loads on the rotor spindles and hinge pins, shortening their safe lifespan. Without this directive, these critical components could fail in flight, potentially causing catastrophic rotor failure and crash.\n\n**What must be done:**\nOperators must follow the instructions in **Eurocopter Service Bulletin No. 01.00.44** (a manufacturer's technical notice) to remove affected parts from service. This became mandatory from **15 August 1996**.\n\n**Key terms explained:**\n- **Airworthiness Directive (AD):** A legally enforceable safety order that aircraft owners must comply with to keep their aircraft airworthy\n- **P/N (Part Number):** The manufacturer's unique identifier for a specific component\n- **MOD. 07-43100:** A specific modification kit that reinforces the affected parts\n- **Service Bulletin (SB):** A manufacturer's technical instruction for maintenance or inspection"},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"The directive narrows in-service permissibility by excluding from service spindles and flapping hinge pins that have not been reinforced or modified per MOD.07-43100. The Applicability clause limits the affected population to specified models and part numbers, and the Background explains that ageing-related tests produced findings that reduced the life limits of those parts; together these elements represent a change from prior allowance to now requiring removal of unreinforced parts (Applicability; Background)."},"complexity_factors":["References an external manufacturer Service Bulletin (dependency on Eurocopter AS332 SB No. 01.00.44) (Requirement)","Specific part numbers and modification status determine applicability, requiring accurate maintenance records and parts identification (Applicability)","Compliance date creates a fixed deadline for action and fleet scheduling (Compliance)","Technical assessment and execution (inspection, modification or replacement) require specialised maintenance capability and parts availability (Requirement; Background)","No alternative compliance mechanisms or exemptions are stated in the directive text (Requirement)"],"plain_english_summary":"The Civil Aviation Safety Authority requires operators of Eurocopter AS332 Super Puma models C, C1, L and L1 to remove certain main rotor spindles and flapping hinge pins from service unless they’ve been reinforced per MOD.07‑43100, following Eurocopter AS332 Service Bulletin No. 01.00.44. Effective 15 August 1996, this targets parts whose life limits were reduced by ageing-induced load increases on frequency adapters. Operators/owners must inspect, modify or replace affected parts and bear the associated costs and downtime."}},"importantCases":[],"_links":{"self":"/api/acts/ad-s-puma-23-main-rotor-spindles-and-flapping-hinge-pins","history":"/api/acts/ad-s-puma-23-main-rotor-spindles-and-flapping-hinge-pins/history","analysis":"/api/acts/ad-s-puma-23-main-rotor-spindles-and-flapping-hinge-pins/analysis","conflicts":"/api/acts/ad-s-puma-23-main-rotor-spindles-and-flapping-hinge-pins/conflicts","importantCases":"/api/acts/ad-s-puma-23-main-rotor-spindles-and-flapping-hinge-pins/important-cases","documents":"/api/acts/ad-s-puma-23-main-rotor-spindles-and-flapping-hinge-pins/documents"}}