{"id":"F2006L02878","name":"AD/DO 328/66 - Hydraulic System Modifications","slug":"ad-do-328-66-hydraulic-system-modifications","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":60128,"registerId":"commonwealth-F2006L02878-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 328/66 | Hydraulic System Modifications | 10/2006 |\n| ------------ | ------------------------------ | ------- |\n\n| Applicability: | Dornier 328-100 aeroplanes with the following serial numbers: 3016, 3024, 3026, 3027, 3031, 3034, 3042, 3046, 3049, 3054, 3062, 3066, 3067, 3069, 3071, 3074, 3078 up to 3083, 3085 and 3086 with active ground spoiler installed (option 040-001).                                                           |\n| -------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | 1. Carry out installation of additional hydraulic lines together with an additional shutoff valve; or2. Replace the hydraulic line and removal of the shut off valve in accordance Dornier 328 SB-328-29-269.Note: LBA AD 1998-031/2 dated 10 September 1998 refers.                                          |\n| Compliance:    | Within 30 days after the effective date of this AD unless previously accomplished.                                                                                                                                                                                                                            |\n|                | This Airworthiness Directive becomes effective on 28 September 2006.                                                                                                                                                                                                                                          |\n| Background:    | Calculations have shown that it is theoretical possible for ground spoiler actuators to unlock by high pressure in the hydraulic return line. This problem is covered bySB-328-29-237. The new SB-328-29-269 describes a second technical solution as an alternate means of compliance for the SB-328-29-237. |\n\n![](image.001.png)  \nJames Coyne  \nDelegate of the Civil Aviation Safety Authority\n\n14 August 2006","sortOrder":0},{"sectionNumber":"AD/DO 328/66","sectionType":"part","heading":"AD/DO 328/66","content":"## AD/DO 328/66","sortOrder":1},{"sectionNumber":"Hydraulic System Modifications","sectionType":"part","heading":"Hydraulic System Modifications","content":"## Hydraulic System Modifications","sortOrder":2},{"sectionNumber":"10/2006","sectionType":"part","heading":"10/2006","content":"## 10/2006","sortOrder":3}],"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 is a standard, narrow Airworthiness Directive targeting a specific technical defect in specific aircraft. It has not expanded beyond its original safety purpose."},"complexity_factors":["Very short document (under 300 words)","Only 2 compliance options with clear alternative paths","Single defined applicability criterion (specific serial numbers plus one equipment option)","No nested exceptions or conditional logic","Simple temporal compliance requirement (30 days from effective date)","Cross-reference to only 2 external technical documents (German LBA AD and Dornier Service Bulletins) with clear hierarchy"],"plain_english_summary":"This mandatory CASA Airworthiness Directive targets 21 specific Dornier 328‑100 aircraft fitted with active ground spoilers. It responds to a theoretical risk that high pressure in the hydraulic return line could accidentally unlock ground spoiler actuators and affect flight control. \n\nWithin 30 days of 28 Sep 2006 operators must modify the hydraulic system by either adding lines and a shutoff valve or replacing the line and removing the valve per Dornier Service Bulletin 328‑29‑269. Compliance is legally required."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"This AD expands available compliance options relative to the earlier service action by accepting a second technical solution via SB-328-29-269 as an alternate means of compliance to the problem addressed in SB-328-29-237. It therefore changes the practical scope of required work by allowing operators to choose between two prescribed corrective actions, while restricting applicability to identified serial numbers with the active ground spoiler option (Requirement; Background; Applicability)."},"complexity_factors":["Narrow applicability limited to a specific list of serial numbers and to aircraft with option 040-001, requiring operators to check individual aircraft status (Applicability).","Two alternate technical compliance methods are offered, which require operators and maintenance organisations to select and implement one (Requirement; SB-328-29-269).","Reference to an external service bulletin (SB-328-29-269) and a prior bulletin (SB-328-29-237) creates dependence on manufacturer documentation for exact workscopes and procedures (Requirement; Background).","Short mandated compliance window of 30 days imposes scheduling and resource pressure on operators and maintenance providers (Compliance).","Technical nature of hydraulic-system work requires certified maintenance capability and parts, producing a measurable cost and operational downtime for the aircraft operator (Requirement).","Regulatory issuance is deterministic (CASA AD effective date stated); little administrative discretion is provided to operators aside from choosing between the two prescribed methods (Compliance; Requirement).","Cross-reference to LBA AD 1998-031/2 indicates prior regulatory action that may affect interpretation or tracing of compliance history (Requirement)."],"plain_english_summary":"This Airworthiness Directive requires operators of specified Dornier 328‑100 aeroplanes fitted with the active ground spoiler option (040‑001) to either install extra hydraulic lines and an additional shutoff valve, or replace the hydraulic line and remove the shutoff valve per Dornier SB‑328‑29‑269, within 30 days of the AD’s effective date (28 Sept 2006) (Requirement; Applicability; Compliance). It responds to a theoretical risk that high pressure in the hydraulic return line could unlock ground spoiler actuators (Background)."}},"importantCases":[],"_links":{"self":"/api/acts/ad-do-328-66-hydraulic-system-modifications","history":"/api/acts/ad-do-328-66-hydraulic-system-modifications/history","analysis":"/api/acts/ad-do-328-66-hydraulic-system-modifications/analysis","conflicts":"/api/acts/ad-do-328-66-hydraulic-system-modifications/conflicts","importantCases":"/api/acts/ad-do-328-66-hydraulic-system-modifications/important-cases","documents":"/api/acts/ad-do-328-66-hydraulic-system-modifications/documents"}}