{"id":"F2006L01335","name":"AD/DO 328/59 - Hydraulic Pressure Dump and Relief Valve","slug":"ad-do-328-59-hydraulic-pressure-dump-and-relief-valve","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":58844,"registerId":"commonwealth-F2006L01335-current","compilationNumber":null,"startDate":"2026-04-02","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 328/59 | Hydraulic Pressure Dump and Relief Valve | 6/2006 |\n| ------------ | ---------------------------------------- | ------ |\n\n| Applicability: | Dornier 328-100 aeroplanes Serial Numbers 3005 through 3095 inclusive.                                                                                                                                                                                   |\n| -------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | Unless previously accomplished replace the pressure dump and relief valve Part Number (P/N) ZHV29-1 with valve P/N ZHV29-2.Note 1: LBA AD 97-072 dated 27 March 1997refers.Note 2: Dornier 328 Service Bulletin No. 328-29-205 pertains to this subject. |\n| Compliance:    | Within 30 days after the effective date of this AD.                                                                                                                                                                                                      |\n|                | This Airworthiness Directive becomes effective on 8 June 2006.                                                                                                                                                                                           |\n| Background:    | The pressure dump and relief valve may have a thin section in the housing and may have been overtorqued during manufacture. This may lead to hydraulic leakage from the valve and loss of the hydraulic system from the aeroplane.                       |\n\n![](image.001.png)  \nJames Coyne  \nDelegate of the Civil Aviation Safety Authority\n\n28 April 2006","sortOrder":0},{"sectionNumber":"AD/DO 328/59","sectionType":"part","heading":"AD/DO 328/59","content":"## AD/DO 328/59","sortOrder":1},{"sectionNumber":"Hydraulic Pressure Dump and Relief Valve","sectionType":"part","heading":"Hydraulic Pressure Dump and Relief Valve","content":"## Hydraulic Pressure Dump and Relief Valve","sortOrder":2},{"sectionNumber":"6/2006","sectionType":"part","heading":"6/2006","content":"## 6/2006","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 mechanical defect in specific aircraft. It has not expanded beyond its original safety purpose."},"complexity_factors":["Very short document (approximately 200 words of substantive content)","Only 2 defined part numbers (ZHV29-1 and ZHV29-2)","Single, unambiguous compliance requirement with clear deadline","No cross-references to other legislation or complex conditional logic","Narrow applicability (specific aircraft model and serial number range)","Straightforward background explanation without technical sub-paragraphs or exceptions"],"plain_english_summary":"This AD orders owners/operators of Dornier 328‑100 aircraft (S/N 3005–3095) to replace a faulty hydraulic pressure dump/relief valve (P/N ZHV29‑1) with an improved ZHV29‑2 within 30 days. The valve’s thin/damaged housing can leak and cause complete hydraulic system loss, risking landing gear, brakes and flight‑control failures."},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The instrument maintains a narrowly targeted corrective action: replace valve P/N ZHV29-1 with P/N ZHV29-2 on Dornier 328-100 aeroplanes SN 3005–3095 within 30 days. The text provides no amendments or expansions to that original corrective scope; applicability, required action and compliance timeframe are specified and unchanged in this document (Applicability; Requirement; Compliance)."},"complexity_factors":["Narrow applicability: single aircraft type and limited serial number range (SN 3005–3095) reduces scope.","Single technical action required: replace one specific part number (P/N ZHV29-1 → ZHV29-2).","Short compliance window: mandatory action within 30 days increases logistical and scheduling pressure on operators (Compliance).","Safety-critical context: hydraulic system failure risk increases urgency and removes flexibility on deferral.","Cross-references: cites Dornier Service Bulletin No. 328-29-205 and LBA AD 97-072, requiring alignment with manufacturer and foreign regulator instructions (Requirement; Background).","No alternative means of compliance or discretionary exemptions stated in the text, so obligation is direct and binary."],"plain_english_summary":"This directive requires operators of Dornier 328‑100 aeroplanes (serial numbers 3005–3095) to replace hydraulic pressure dump and relief valve P/N ZHV29‑1 with P/N ZHV29‑2 within 30 days (Requirement; Compliance). The regulator records that a thin housing section and possible over‑torquing could cause hydraulic leakage and loss of hydraulic system function (Background); the compliance cost and fitting fall to aircraft owners/operators and their maintenance organisations and rely on availability of the replacement valve and Dornier Service Bulletin No. 328‑29‑205."},"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-328-59-hydraulic-pressure-dump-and-relief-valve","history":"/api/acts/ad-do-328-59-hydraulic-pressure-dump-and-relief-valve/history","analysis":"/api/acts/ad-do-328-59-hydraulic-pressure-dump-and-relief-valve/analysis","conflicts":"/api/acts/ad-do-328-59-hydraulic-pressure-dump-and-relief-valve/conflicts","importantCases":"/api/acts/ad-do-328-59-hydraulic-pressure-dump-and-relief-valve/important-cases","documents":"/api/acts/ad-do-328-59-hydraulic-pressure-dump-and-relief-valve/documents"}}