{"id":"F2006B01876","name":"AD/A320/129 Amdt 1 - Parking Brake Operating Valve","slug":"ad-a320-129-amdt-1-parking-brake-operating-valve","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":41072,"registerId":"commonwealth-F2006B01876-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/A320/129 Amdt 1 - Parking Brake Operating Valve","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)  \n\nAIRWORTHINESS DIRECTIVE\n\n![](image.001.png)\n\n![](image.001.png)  \nFor the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/A320/129 and issues the following AD under subregulation 39.1 (1) of CAR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.\n\nAirbus Industrie A319, A320 and A321 Series Aeroplanes\n\nAD/A320/129\n\nAmdt 1\n\n  \nParking Brake Operating Valve 5/2002\n\nApplicability: Airbus A319, A320 and A321 aeroplanes as specified in DGAC AD 2001-384(B)R1. Requirement: Action per DGAC AD 2001-384(B) R1.\n\nCompliance: As detailed in the requirement document with a revised effective date of 16 May 2002.\n\nThis Amendment becomes effective on 16 May 2002.\n\nBackground: Airbus Industrie has advised that certain Messier Bugatti parking brake operating valves are susceptible to leakage of hydraulic fluid. This could lead to depletion of the Yellow hydraulic system fluid and render the Alternate Braking and Emergency Braking System inoperative.\n\nThis amendment requires the repair or replacement of the affected components by 31 December 2002.\n\nThe original issue of this directive became effective on 24 October 2001.\n\n![](image.002.png)  \n\nEugene Paul Holzapfel\n\nDelegate of the Civil Aviation Safety Authority 27 March 2002\n\n![](image.001.png)  \n\nThe above AD is notified in the Commonwealth of Australia Gazette on 24 April 2002.\n\n  \n\nPage 1 of 1","sortOrder":0}],"analysis":{"flash_summary_failed":{"failed":true,"reason":"Unauthenticated. Configure AI_GATEWAY_API_KEY or use a provider module. Learn more: https://ai-sdk.dev/unauthenticated-ai-gateway","source":"analysis-cron"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This amendment maintains the original scope — addressing the same parking brake valve defect on the same aircraft models. The only change is administrative: updating the effective date and compliance deadline. The safety purpose remains unchanged."},"complexity_factors":["Very short document (1 page)","No defined terms section — relies on external reference to French aviation authority document (DGAC AD 2001-384(B)R1)","Simple conditional structure: single applicability trigger (aircraft model) → single required action (repair/replace) → single deadline","Minimal cross-referencing: only references to the French DGAC directive and Civil Aviation Regulations 1998, subregulation 39.1(1)","No nested exceptions or conditional sub-clauses"],"plain_english_summary":"This Airworthiness Directive from CASA requires Australian operators of certain Airbus A319/A320/A321 jets to repair or replace Messier Bugatti parking-brake operating valves that can leak and drain the Yellow hydraulic system, risking loss of backup and emergency brakes. Compliance is mandatory by 31 December 2002. This amendment revokes the 2001 directive and reissues it with an effective date of 16 May 2002 to set the clear compliance deadline."},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"This amendment does not materially expand the subject matter or parties covered by the original directive. It revokes the earlier AD and reissues it with a revised effective date (16 May 2002) and an explicit compliance deadline for repair or replacement (31 December 2002). The aircraft types affected and the required corrective action remain those specified in the referenced DGAC AD 2001-384(B) R1; the amendment therefore clarifies timing rather than broadening scope."},"complexity_factors":["Short, single-page AD with limited sections (Applicability; Requirement; Compliance; Background).","Direct cross-reference to an external technical document (DGAC AD 2001-384(B) R1) for the detailed corrective actions.","One concrete compliance deadline (repair/replacement by 31 December 2002) and one revised effective date (16 May 2002).","No layered exceptions, few defined terms, and minimal conditional logic.","Involves revocation and reissue of a prior AD, but no expansion of applicability or new regulatory mechanisms."],"plain_english_summary":"**What this instrument does (mechanically)**\n\n- Revokes a prior airworthiness directive (AD/A320/129) and reissues it in amended form. (See heading and first paragraph.)\n- Makes mandatory the corrective actions specified in the French DGAC airworthiness directive DGAC AD 2001-384(B) R1 for certain Airbus A319, A320 and A321 aeroplanes. (Applicability; Requirement.)\n- Sets the AD's revised effective date as 16 May 2002 and requires the affected parking brake operating valves to be repaired or replaced by 31 December 2002. (Compliance; Background.)\n\n**Who is affected**\n\n- Operators and owners of Airbus A319, A320 and A321 aircraft that fall within the applicability of DGAC AD 2001-384(B) R1. (Applicability.)\n- Maintenance organisations and repair stations that will carry out the repairs or replacements called for by the referenced DGAC AD. (Requirement.)\n\n**Why it matters (official rationale and practical effect)**\n\n- The directive responds to a safety concern: certain Messier Bugatti parking brake operating valves can leak hydraulic fluid. If leakage depletes the Yellow hydraulic system, the plane's Alternate Braking and Emergency Braking System could become inoperative. The AD therefore mandates repair or replacement of the affected components to correct that unsafe condition. (Background; Requirement.)\n\n**Practical consequences and implementation mechanics**\n\n- Aircraft operators must follow the actions and instructions set out in DGAC AD 2001-384(B) R1. The Australian AD enforces that foreign-authority instruction domestically by reference. (Requirement.)\n- Operators will need to schedule maintenance to repair or replace the valves by the specified deadline (31 December 2002). This will typically involve aircraft downtime, labour, parts procurement and paperwork to record compliance. (Compliance; Background.)\n- The AD is issued under the CASA delegate's power in subregulation 39.1(1) of the Civil Aviation Regulations 1998, meaning CASA enforces the action and may monitor compliance. (First paragraph.)\n\n**Costs, incentives and trade-offs — concrete mechanisms**\n\n- Who pays: aircraft operators pay for inspections, repairs/replacements, parts and associated aircraft downtime. (Implicit in Requirement/Compliance.)\n- Incentives: operators have a direct safety and regulatory incentive to comply before the deadline to keep the aircraft certificated and commercially available. Delaying compliance risks regulatory action and removes aircraft from service. (Compliance.)\n- Opportunity cost: time spent out of service for maintenance reduces available flying hours and could reduce revenue for operators. (Compliance/Burden of maintenance.)\n- Supply and implementation risk: if replacement valves or approved repair facilities are limited, operators may face scheduling delays or higher costs. The AD references a DGAC document that will contain technical instructions; reliance on an external authority can create administrative steps (obtaining the service instructions, arranging approved repairs). (Requirement; Background.)\n- Administrative burden: operators must track applicability, implement the referenced DGAC procedures, and keep records demonstrating compliance to CASA. (Requirement/Compliance.)\n\n**Effects on private enterprise and market aspects**\n\n- Maintenance market: demand for parts and approved repair services for Messier Bugatti valves will rise among affected operators; this benefits MROs and parts suppliers that are able to service the valve type. If only a few suppliers or authorised repair stations exist, pricing and scheduling may be affected. (Implied by Requirement/Background.)\n- Competition and contract freedom: the AD does not itself name suppliers; however, compliance often depends on manufacturers' or OEM-authorised procedures. Operators remain free to contract with any provider authorised to perform the required work under applicable aviation maintenance rules. (Requirement.)\n- Prices and productivity: short-term increases in maintenance costs and reduced aircraft availability are likely; longer-term effects depend on supply capacity and market responses. (Compliance/Background.)\n\n**Concentrated benefits and diffuse costs**\n\n- Benefits are concentrated in reduced safety risk for each affected aircraft and in the operators' avoidance of regulatory penalties. (Background/Requirement.)\n- Costs are borne mainly by the commercial operators of the covered Airbus types and the MRO sector that performs the work; for the travelling public there is no direct charge in the AD text, but operators may internalise costs in fares or service availability. (Requirement/Compliance.)\n\n**Discretion and legal mechanics**\n\n- CASA issued the AD by revoking the earlier AD and reissuing it with the revised effective date. The delegate exercised the statutory power in subregulation 39.1(1) to require action to correct an unsafe condition. The AD enforces compliance with the referenced DGAC AD (an external technical document), rather than setting out technical steps in full within this Australian instrument. (First paragraph; Requirement.)\n\n**Summary takeaway**\n\n- Mechanically, this AD makes it mandatory for affected A319/A320/A321 aircraft to follow the DGAC repair or replacement instructions for certain Messier Bugatti parking brake valves, with an effective date of 16 May 2002 and a compliance deadline of 31 December 2002. The stated safety reason is leakage risk that could disable alternate/emergency braking by depleting the Yellow hydraulic system. Operators carry the costs and operational burden of carrying out the mandated maintenance and recording compliance. (Applicability; Requirement; Compliance; Background.)"}},"importantCases":[],"_links":{"self":"/api/acts/ad-a320-129-amdt-1-parking-brake-operating-valve","history":"/api/acts/ad-a320-129-amdt-1-parking-brake-operating-valve/history","analysis":"/api/acts/ad-a320-129-amdt-1-parking-brake-operating-valve/analysis","conflicts":"/api/acts/ad-a320-129-amdt-1-parking-brake-operating-valve/conflicts","importantCases":"/api/acts/ad-a320-129-amdt-1-parking-brake-operating-valve/important-cases","documents":"/api/acts/ad-a320-129-amdt-1-parking-brake-operating-valve/documents"}}