{"id":"F2006B09169","name":"AD/DHC-8/14 - Oxygen Line Chafing","slug":"ad-dhc-8-14-oxygen-line-chafing","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":52910,"registerId":"commonwealth-F2006B09169-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/DHC-8/14 - Oxygen Line Chafing","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)  \nBombardier (Boeing Canada/De Havilland) DHC-8 Series Aeroplanes\n\nAD/DHC-8/14 Oxygen Line Chafing 6/91 TX\n\nApplicability: All models DHC-8 100 and 300 series aircraft Serial No’s 003 through 271.\n\nRequirement: 1. Inspect and repair in accordance with Boeing Canada de Havilland Division Alert SB A8-35-5 Rev “A”.\n\n2. Tape and wrap in accordance with Boeing Canada de Havilland Division Alert SB A8-35-5 Rev “A”.\n\nNote: Transport Canada Emergency AD CF-91-97 also refers.\n\nCompliance: 1. Prior to 25 April 1991.\n\n2. Within 500 hours time in service after 13 June 1991.\n\nBackground: There has been an occurrence of an electrical cable chafing an oxygen line beneath the crew compartment floor and rupturing the line. Action in accordance with this AD is necessary to prevent a severe oxygen-fed fire due to possible arcing between electrical feeder cable and crew oxygen line.\n\nNote: Boeing Canada advises that all operators have been notified.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted safety directive addressing a specific mechanical defect in specific aircraft. It has not expanded beyond its original purpose of mandating inspection and repair of oxygen line chafing issues."},"complexity_factors":["Single, specific technical issue (oxygen line chafing)","Only 2 compliance requirements with clear deadlines","No defined terms section or complex interpretation provisions","Minimal conditional logic — applicability is straightforward (specific aircraft serial numbers)","Short document (approximately 200 words)","References external technical documents (Service Bulletin) rather than embedding complex technical specifications"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — essentially a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) for specific aircraft.\n\n**What it does:**\nOrders owners and operators of certain Bombardier DHC-8 aircraft (also known as Dash 8) to inspect and fix a dangerous design flaw where electrical cables can rub against (\"chafe\") oxygen lines under the cockpit floor. If the oxygen line ruptures and electrical arcing occurs, it could cause a catastrophic fire.\n\n**Who it affects:**\n- Owners and operators of DHC-8 100 and 300 series aircraft with serial numbers 003 through 271\n- Maintenance engineers working on these aircraft\n\n**What must be done:**\n1. **Immediate inspection and repair** — completed before 25 April 1991\n2. **Additional protective taping and wrapping** — within 500 flight hours after 13 June 1991\n\nBoth actions must follow specific technical instructions from the manufacturer (Boeing Canada de Havilland Alert Service Bulletin A8-35-5 Revision \"A\").\n\n**Why it matters:**\nThis addresses a real incident where an electrical cable wore through an oxygen line. Pure oxygen + electrical sparks = potential for a devastating fire that could bring down the aircraft. The directive makes the fix legally mandatory rather than optional."},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"There is no indication in the text provided that the scope has been altered from its original targeting. The AD applies to all DHC-8 100 and 300 series aircraft with serial numbers 003 through 271 (Applicability) and prescribes the remedial actions and deadlines intended to address the occurrence described (Background; Requirement; Compliance)."},"complexity_factors":["Narrow applicability: limited to DHC-8 100 and 300 series, serial numbers 003–271 (Applicability).","Two discrete mandated actions (inspect/repair; tape/wrap) rather than multiple conditional pathways (Requirement 1–2).","External technical standard referenced: Boeing Canada de Havilland Division Alert SB A8-35-5 Rev \"A\" determines the technical steps (Requirement 1–2).","Fixed compliance deadlines: one calendar-date deadline and one service-hours deadline (Compliance).","Safety-critical subject matter increases practical urgency and may require aircraft downtime, affecting scheduling (Background; Compliance).","Cross-reference to a foreign regulator's Emergency AD (Transport Canada CF-91-97) requires operators to be aware of related international guidance (Note)."],"plain_english_summary":"This airworthiness directive requires operators of Bombardier (De Havilland) DHC‑8 Series 100 and 300 aeroplanes (serial nos. 003–271) to inspect for and repair a cable/oxygen‑line chafe hazard and to apply protective tape/wrap in accordance with Boeing Canada De Havilland Alert Service Bulletin A8‑35‑5 Rev A. \n\nInspections/repairs must be done by 25 April 1991 and the tape/wrap fitted within 500 hours TIS after 13 June 1991; operators fund and schedule the work to prevent possible arcing and an oxygen‑fed fire."}},"importantCases":[],"_links":{"self":"/api/acts/ad-dhc-8-14-oxygen-line-chafing","history":"/api/acts/ad-dhc-8-14-oxygen-line-chafing/history","analysis":"/api/acts/ad-dhc-8-14-oxygen-line-chafing/analysis","conflicts":"/api/acts/ad-dhc-8-14-oxygen-line-chafing/conflicts","importantCases":"/api/acts/ad-dhc-8-14-oxygen-line-chafing/important-cases","documents":"/api/acts/ad-dhc-8-14-oxygen-line-chafing/documents"}}