{"id":"F2006L00748","name":"AD/DO 328/56 - Rudder Torsion Bar Retainer","slug":"ad-do-328-56-rudder-torsion-bar-retainer","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":136771,"registerId":"commonwealth-F2006L00748-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Dornier 328 Series Aeroplanes","sectionType":"division","heading":"Dornier 328 Series Aeroplanes","content":"### Dornier 328 Series Aeroplanes\n\n| AD/DO 328/56 | Rudder Torsion Bar Retainer | 4/2006 |\n| ------------ | --------------------------- | ------ |\n\n| Applicability: | Dornier 328-100 aeroplanes serial numbers, 3005 up to 3098, 3100, 3101, 3104, 3106, 3107, 3109, 3110, 3112, 3113, 3115, 3117 and 3119.                                                                                              |\n| -------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | Install a retainer instead of a washer in accordance with the instructions given in Dornier 328 Service Bulletin No. SB-328-27-298 Revision 1, dated 21 November 2002 or later LBA approved revisions.Note: LBA AD 2003-104 refers. |\n| Compliance:    | Within 30 days after the effective date of this AD unless previously accomplished.                                                                                                                                                  |\n|                | This Airworthiness Directive becomes effective on 13 April 2006.                                                                                                                                                                    |\n| Background:    | The washer is currently installed may not provide satisfactory retention to stop the spring tab torsion bar slipping through.                                                                                                       |\n\n![](image.001.png)  \nJames Coyne  \nDelegate of the Civil Aviation Safety Authority\n\n3 March 2006","sortOrder":0},{"sectionNumber":"AD/DO 328/56","sectionType":"part","heading":"AD/DO 328/56","content":"## AD/DO 328/56","sortOrder":1},{"sectionNumber":"Rudder Torsion Bar Retainer","sectionType":"part","heading":"Rudder Torsion Bar Retainer","content":"## Rudder Torsion Bar Retainer","sortOrder":2},{"sectionNumber":"4/2006","sectionType":"part","heading":"4/2006","content":"## 4/2006","sortOrder":3}],"analysis":{"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The AD does not broaden the range of actions beyond replacing the washer with a retainer on listed airframes. It targets a specific retention defect identified in the background and requires modification per a defined service bulletin for specified serial numbers (Applicability; Requirement; Background). There is no text in the instrument indicating an expansion or narrowing of scope from that remedial objective."},"complexity_factors":["Narrow technical scope: single part change (washer → retainer) on a specific control component (Background; Requirement).","Limited applicability: only specified Dornier 328‑100 serial numbers are affected (Applicability).","Prescriptive compliance: work must follow a specific service bulletin (SB‑328‑27‑298 Rev 1) or later LBA‑approved revision (Requirement).","Short compliance window: action due within 30 days of the AD effective date increases scheduling pressure for operators (Compliance).","Dependence on parts and maintenance access: operators must source retainer parts and allocate maintenance resources, creating direct costs and logistical burden (Requirement; Compliance).","Regulatory linkage: references the LBA approval process and an LBA AD, introducing cross‑jurisdictional approval dependence (Requirement; Background)."],"plain_english_summary":"Requires operators of specified Dornier 328‑100 aeroplanes (listed serial numbers) to replace the existing washer on the rudder spring‑tab torsion bar with a retainer, following Dornier 328 Service Bulletin SB‑328‑27‑298 Revision 1 or later LBA‑approved revisions. (Requirement; Compliance) The measure is intended to stop the torsion bar slipping through the washer; operators must comply within 30 days of the AD’s effective date and will bear the maintenance, parts and scheduling costs."},"flash_summary_failed":{"failed":true,"reason":"A positive credit balance is required for all requests, including BYOK, so fallback providers remain available. Add credits at https://vercel.com/d?to=%2F%5Bteam%5D%2F%7E%2Fai%3Fmodal%3Dtop-up to continue.","source":"analysis-cron"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard, narrow Airworthiness Directive addressing a specific mechanical defect in a specific aircraft type. It has not expanded beyond its original safety purpose."},"complexity_factors":["Very short document (approximately 200 words)","Only one substantive requirement with clear reference to external technical document (Service Bulletin)","Simple applicability test based on aircraft serial numbers","Single compliance deadline with straightforward exception ('unless previously accomplished')","No defined terms section, no cross-referencing to other legislation, no conditional logic or nested exceptions","Background explanation is plain language and brief"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — essentially a mandatory safety order for aircraft owners and operators. It applies to specific **Dornier 328-100 aeroplanes** (a type of regional turboprop aircraft) with particular serial numbers.\n\n**What it requires:**\n- Aircraft owners must **replace a washer with a retainer** on the rudder's torsion bar (a component that helps control the aircraft's steering).\n- This must be done following specific technical instructions from Dornier Service Bulletin SB-328-27-298.\n\n**Why it matters:**\n- The existing washer might not hold the spring tab torsion bar securely, allowing it to **slip through**. This could affect rudder control — a serious flight safety issue.\n\n**When it must be done:**\n- Within **30 days** of 13 April 2006 (unless already fixed).\n\n**Who issued it:**\n- The **Civil Aviation Safety Authority (CASA)** — Australia's aviation safety regulator — through a delegated officer."}},"importantCases":[],"_links":{"self":"/api/acts/ad-do-328-56-rudder-torsion-bar-retainer","history":"/api/acts/ad-do-328-56-rudder-torsion-bar-retainer/history","analysis":"/api/acts/ad-do-328-56-rudder-torsion-bar-retainer/analysis","conflicts":"/api/acts/ad-do-328-56-rudder-torsion-bar-retainer/conflicts","importantCases":"/api/acts/ad-do-328-56-rudder-torsion-bar-retainer/important-cases","documents":"/api/acts/ad-do-328-56-rudder-torsion-bar-retainer/documents"}}