{"id":"F2005L03948","name":"AD/DO 328/15 - Relief Restrictor Valve","slug":"ad-do-328-15-relief-restrictor-valve","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":39805,"registerId":"commonwealth-F2005L03948-current","compilationNumber":null,"startDate":"2026-04-01","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 328/15 | Relief Restrictor Valve | 1/2006 |\n| ------------ | ----------------------- | ------ |\n\n| Applicability: | Dornier 328-100 aeroplanes serial numbers: 3016, 3024, 3026, 3027, 3031, 3034, 3042, 3046, 3049, 3054, 3062, 3066, 3067, 3069, 3071, 3074, 3078 up to 3083, 3085, 3086, 3090 up to 3098 fitted with relief restrictor valve P/N ZRV87-2.                                      |\n| -------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | Unless previously accomplished, replace the relief restrictor valves P/N ZRV87-2 with new valves P/N ZRV87-3 in accordance with Dornier 328 Service Bulletin No. SB-328-27-243 Revision 1 dated 18 December 1997 or later LBA approved revision.Note: LBA AD 1998-046 refers. |\n| Compliance:    | Prior to the issue of an Australian C of A.                                                                                                                                                                                                                                   |\n|                | This Airworthiness Directive becomes effective on 19 January 2006.                                                                                                                                                                                                            |\n| Background:    | On aircraft with active ground spoilers, the higher internal leakage of the P/NZRV87-2 valve in combination with an additional failure could result in unlocking of the ground spoiler actuators.                                                                             |\n\n![](image.001.png)  \nJames Coyne  \nDelegate of the Civil Aviation Safety Authority\n\n29 November 2005","sortOrder":0},{"sectionNumber":"AD/DO 328/15","sectionType":"part","heading":"AD/DO 328/15","content":"## AD/DO 328/15","sortOrder":1},{"sectionNumber":"Relief Restrictor Valve","sectionType":"part","heading":"Relief Restrictor Valve","content":"## Relief Restrictor Valve","sortOrder":2},{"sectionNumber":"1/2006","sectionType":"part","heading":"1/2006","content":"## 1/2006","sortOrder":3}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard, narrow Airworthiness Directive targeting a specific safety defect in specific aircraft. It has not expanded beyond its original purpose of addressing the identified valve leakage issue."},"complexity_factors":["Single, specific technical requirement (valve replacement)","Limited applicability (24 specific aircraft serial numbers)","One defined part number reference (P/N ZRV87-2/ZRV87-3)","Single compliance pathway (follow specific service bulletin)","No nested exceptions or conditional logic","Short document (approximately 150 words of substantive content)","Clear, unambiguous deadline tied to certificate issuance"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — a mandatory safety order issued by Australia's aviation regulator (CASA) requiring specific repairs or modifications to aircraft.\n\n**What it does:**\nOrders owners/operators of certain Dornier 328-100 aeroplanes to replace a specific hydraulic valve (part number ZRV87-2) with an improved version (ZRV87-3).\n\n**Who it affects:**\nOnly 24 specific Dornier 328-100 aircraft (listed by serial numbers) that are fitted with the old valve. These are regional turboprop aircraft commonly used for short-haul flights.\n\n**Why it matters:**\nThe old valve has excessive internal leakage. If this combines with another mechanical failure, it could cause the ground spoilers (wing panels that disrupt airflow to slow the plane after landing) to unlock unexpectedly. This creates a serious safety risk during landing and ground operations.\n\n**When action is required:**\nBefore the aircraft can receive or renew its Australian Certificate of Airworthiness (C of A) — essentially, before it can be legally flown in Australia.\n\n**The fix:**\nReplace the valve following the manufacturer's official service instructions (Dornier Service Bulletin SB-328-27-243)."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The directive's scope is limited to listed Dornier 328-100 serial numbers fitted with valve P/N ZRV87-2 and mandates replacement with P/N ZRV87-3 before issue of an Australian Certificate of Airworthiness. The text contains no indication that this AD changes or expands an earlier mandate; it cross-references the Dornier Service Bulletin and an LBA AD for technical detail but does not alter the listed applicability or required action."},"complexity_factors":["Narrow applicability: specific Dornier 328-100 serial numbers only","Single, discrete technical action required (replace one P/N with another)","Fixed compliance trigger: must be done prior to issuance of Australian Certificate of Airworthiness","Dependence on an external technical document: Dornier Service Bulletin SB-328-27-243 or later LBA‑approved revision","Safety rationale tied to a specific failure mode (internal valve leakage combined with an additional failure)","Administrative burden on operators to source approved replacement parts and document compliance","Reference to an overseas authority (LBA AD 1998-046) creates cross-jurisdictional conformity requirement","Enforcement through CASA delegate decision reduces discretionary flexibility for affected operators"],"plain_english_summary":"This Airworthiness Directive requires operators of the listed Dornier 328‑100 aeroplanes fitted with relief restrictor valve P/N ZRV87‑2 to replace those valves with P/N ZRV87‑3, using Dornier Service Bulletin SB‑328‑27‑243 (or a later LBA‑approved revision). The replacement must be completed before the issue of an Australian Certificate of Airworthiness.\n\nThe measure responds to higher internal leakage in the older valve that, with a separate failure, could unlock ground spoiler actuators. Aircraft owners/operators pay for parts and installation; the Civil Aviation Safety Authority (delegate) enforces compliance."},"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"}},"importantCases":[],"_links":{"self":"/api/acts/ad-do-328-15-relief-restrictor-valve","history":"/api/acts/ad-do-328-15-relief-restrictor-valve/history","analysis":"/api/acts/ad-do-328-15-relief-restrictor-valve/analysis","conflicts":"/api/acts/ad-do-328-15-relief-restrictor-valve/conflicts","importantCases":"/api/acts/ad-do-328-15-relief-restrictor-valve/important-cases","documents":"/api/acts/ad-do-328-15-relief-restrictor-valve/documents"}}