{"id":"F2006L00749","name":"AD/DO 328/55 - APU Fire Extinguisher Cartridge","slug":"ad-do-328-55-apu-fire-extinguisher-cartridge","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":136772,"registerId":"commonwealth-F2006L00749-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 328/55 | APU Fire Extinguisher Cartridge | 4/2006 |\n| ------------ | ------------------------------- | ------ |\n\n| Applicability: | Dornier 328-100 aeroplanes fitted with an Auxiliary Power Unit (APU).                                                                                                                                     |\n| -------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | Replace the existing cartridge with an improved version as detailed in Dornier 328 Service Bulletin No. SB-328-26-342 dated 2 November 2000 or later LBA approved revisions.Note: LBA AD 2001-292 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 improved APU fire cartridge provides a greater margin of safety and rupture disc opening efficiency.                                                                                                  |\n\n![](image.001.png)  \nJames Coyne  \nDelegate of the Civil Aviation Safety Authority\n\n3 March 2006","sortOrder":0},{"sectionNumber":"AD/DO 328/55","sectionType":"part","heading":"AD/DO 328/55","content":"## AD/DO 328/55","sortOrder":1},{"sectionNumber":"APU Fire Extinguisher Cartridge","sectionType":"part","heading":"APU Fire Extinguisher Cartridge","content":"## APU Fire Extinguisher Cartridge","sortOrder":2},{"sectionNumber":"4/2006","sectionType":"part","heading":"4/2006","content":"## 4/2006","sortOrder":3}],"analysis":{"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"},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The AD enforces the original safety change—replacement of the APU fire extinguisher cartridge on affected Dornier 328-100 aircraft—without expanding affected aircraft types or adding additional obligations beyond following the service bulletin and regulator‑approved revisions (Applicability; Requirement; Compliance)."},"complexity_factors":["Very narrow applicability — only Dornier 328-100 aeroplanes fitted with an APU (Applicability).","Single, discrete technical action required: replace cartridge per specified Service Bulletin (Requirement).","Short compliance window of 30 days creates scheduling/logistics pressure for operators (Compliance).","References to LBA-approved revisions permit only regulator-approved modifications, adding an approval dependency (Requirement: \"or later LBA approved revisions\").","Administrative traceability: operators must record compliance with an AD effective date (Compliance).","Safety rationale is technical and specific (improved rupture‑disc opening efficiency), limiting interpretive ambiguity (Background)."],"plain_english_summary":"This Airworthiness Directive requires operators of Dornier 328-100 aeroplanes fitted with an APU to replace the existing APU fire extinguisher cartridge with the improved cartridge specified in Dornier Service Bulletin SB-328-26-342 (2 Nov 2000) or later LBA‑approved revisions, within 30 days of the AD (effective 13 April 2006). The AD was issued by the Civil Aviation Safety Authority delegate; operators pay for and arrange the replacement, following the service bulletin and any LBA approvals (Applicability; Requirement; Compliance; Background)."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard, narrow Airworthiness Directive focused on a specific safety-critical component replacement. It has not expanded beyond its original purpose of mandating a hardware upgrade for fire safety."},"complexity_factors":["Very short document (under 300 words)","Only one substantive requirement (replace cartridge)","Single cross-reference to Dornier Service Bulletin and German LBA AD","No defined terms section — uses standard aviation terminology only","Simple compliance structure: one deadline, one action, one exception (if already done)","No nested conditions or exceptions"],"plain_english_summary":"Owners and operators of Dornier 328-100 aircraft with an APU must replace the APU fire-extinguisher cartridge with the improved design per Dornier Service Bulletin SB-328-26-342 (or later approved revision) within 30 days of the directive (13 April 2006) unless already done. This mandatory AD fixes a cartridge failure risk that could prevent fire suppression by reliably opening the rupture disc."}},"importantCases":[],"_links":{"self":"/api/acts/ad-do-328-55-apu-fire-extinguisher-cartridge","history":"/api/acts/ad-do-328-55-apu-fire-extinguisher-cartridge/history","analysis":"/api/acts/ad-do-328-55-apu-fire-extinguisher-cartridge/analysis","conflicts":"/api/acts/ad-do-328-55-apu-fire-extinguisher-cartridge/conflicts","importantCases":"/api/acts/ad-do-328-55-apu-fire-extinguisher-cartridge/important-cases","documents":"/api/acts/ad-do-328-55-apu-fire-extinguisher-cartridge/documents"}}