{"id":"F2013L01679","name":"AD/HS 125/161 Amdt 1 - Oxygen System","slug":"ad-hs-125-161-amdt-1-oxygen-system","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":127711,"registerId":"commonwealth-F2013L01679-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"British Aerospace BAe 125 Series Aeropla","sectionType":"division","heading":"British Aerospace BAe 125 Series Aeroplanes","content":"### British Aerospace BAe 125 Series Aeroplanes\n\n| AD/HS 125/161 Amdt 1 | Oxygen System | 19/2013 |\n| -------------------- | ------------- | ------- |\n\n```html\n

Applicability:

Models and series of aeroplanes as listed in the applicable Raytheon Aircraft Service Bulletin(s) (SB) specified in the following table:

Model of Aeroplane

SB No

SB Date

DH.125, HS.125, BH.125 series 1A, 1B, 3A, 3B, 400A, 400B, 401B, 403A,403B, 600A, 600B, 700A, and 700B

SB 35-3169

September 1998

BAe.125 series 800A (C-29A)

SB 35-3171

September 1998

BAe.125 series 800A, 800B, and Hawker 800

SB 35-3034 and
SB 35-3170

September 1998

BAe.125 series 1000A, 1000B, and Hawker 1000

SB 35-3167 and
SB 35-3168

September 1998

Requirement:

1. For Model DH.125, HS.125, BH.125 series 1A, 1B, 3A, 3B, 400A, 400B, 401B, 403A, 403B, 600A, 600B, 700A and 700B aeroplanes:

a. Replace the cadmium plated cone caps in the oxygen system plumbing with improved cone caps, and perform a detailed visual inspection of the removed cone caps, tee-piece and sleeve for evidence of flaking or corrosion; in accordance with SB 35-3169 dated September 1998.

b. If any flaking or corrosion is detected, clean the tee-piece and sleeve, and perform an oxygen system flow check in accordance with the SB.

c. If any discrepancy is found during the flow check, repair the oxygen system in accordance with the SB, except as required by Requirement 5.

\n```\n\n| | 2. For Model BAe.125 series 800A (C-29A) aeroplanes:a. Replace the cadmium plated cone caps in the oxygen system plumbing with improved cone caps, and perform a detailed visual inspection of the removed cone caps, tee-piece and sleeve for evidence of flaking or corrosion; in accordance with SB 35-3171, dated September 1998.b. If any flaking or corrosion is detected, clean the tee-piece and sleeve, and perform an oxygen system flow check in accordance with the SB.c. If any discrepancy is found during the flow check, repair the oxygen system in accordance with the SB, except as required by Requirement 5.3. For Model BAe.125 series 800A and 800B aeroplanes and Model Hawker 800 aeroplanes:Replace the cadmium plated cone caps in the oxygen system plumbing with improved cone caps, and perform a detailed visual inspection of the removed cone caps, tee-piece and sleeve for evidence of flaking or corrosion; in accordance with SB 35-3034 or SB 35-3170, both dated September 1998, as applicable.b. If any flaking or corrosion is detected, clean the tee-piece and sleeve, and perform an oxygen system flow check in accordance with the SB.c. If any discrepancy is found during the flow check, repair the oxygen system in accordance with the SB, except as required by Requirement 5.4. For Model BAe.125 series 1000A and 1000B aeroplanes and Model Hawker series aeroplanes:a. Replace the cadmium plated fittings in the oxygen system plumbing with improved fittings, and perform a detailed visual inspection of the removed fittings and the pipe connections for evidence of flaking or corrosion; in accordance with SB 35-3167 or SB 35-3168, both dated September 1998, as applicable.b. If any flaking or corrosion is detected, clean the pipe connections, and perform an oxygen system flow check in accordance with the SB.c. If any discrepancy is found during the flow check, repair the oxygen system in accordance with the SB, except as required by Requirement 5.5. If any discrepancy is found during a flow check required by Requirements 1, 2, 3 or 4 and the applicable SB specifies to contact the manufacturer for a repair disposition, repair the oxygen system in accordance with a method approved by the Manager, Technical Specialists Section, Certification Standards Branch, Civil Aviation Safety Authority, GPO Box 2005 Canberra ACT 2601, Facsimile(02) 6217 1914. |\n| ----------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |\n| | Note 1: For the purposes of this Directive, a detailed visual inspection is defined as: \"An intensive visual examination of a specific structural area, system, installation, or assembly to detect damage, failure, or irregularity. Available lighting is normally supplemented with a direct source of good lighting at intensity deemed appropriate by the inspector. Inspection aids such as mirror, magnifying lenses, etc., may be used. Surface cleaning and elaborate access procedures may be required.\"Note 2: FAA AD 2000-02-35 Amdt 39-11553 refers. |\n| Compliance: | For Requirement 1.a. - Within 6 months after the effective date of this Directive.For Requirement 1.b. - Before further flight.For Requirement 1.c. - Before further flight.For Requirement 2.a. - Within 6 months after the effective date of this Directive.For Requirement 2.b. - Before further flight.For Requirement 2.c. - Before further flight.For Requirement 3.a. - Within 6 months after the effective date of this Directive.For Requirement 3.b. - Before further flight.For Requirement 3.c. - Before further flight.For Requirement 4.a. - Within 6 months after the effective date of this Directive.For Requirement 4.b. - Before further flight.For Requirement 4.c. - Before further flight.For Requirement 5 - Before further flight. |\n| | The effective date of this Amendment is 10 September 2013. |\n| Background: | Amendment 1 is issued to correct typographical error in Note 2 of the Requirement Section. The FAA AD reference is corrected from 2000-03-35 to 2000-02-35.The Federal Aviation Administration has advised that Raytheon received reports indicating that a field survey revealed that a reaction process was occurring, which resulted in cadmium flaking. The flaking could cause blocking of valves resulting in impairing the function of the oxygen system, which could deprive the crew and passengers of necessary oxygen during an emergency that requires oxygen.This Directive specifies actions designed to prevent flaking of cadmium from certain oxygen system plumbing fittings and cone caps from blocking the valves. |\n\n| | There is no change to initial requirements of the AD.The original issue of this Airworthiness Directive became effective on23 March 2000. |\n| --- | ----------------------------------------------------------------------------------------------------------------------------------------- |\n\n![](image.001.png)\n\nMike Higgins \nDelegate of the Civil Aviation Safety Authority\n\n5 September 2013","sortOrder":0},{"sectionNumber":"AD/HS 125/161 Amdt 1","sectionType":"part","heading":"AD/HS 125/161 Amdt 1","content":"## AD/HS 125/161 Amdt 1","sortOrder":1},{"sectionNumber":"Oxygen System","sectionType":"part","heading":"Oxygen System","content":"## Oxygen System","sortOrder":2},{"sectionNumber":"19/2013","sectionType":"part","heading":"19/2013","content":"## 19/2013","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":4,"scope_assessment":{"changed":false,"description":"This is Amendment 1 to an existing Airworthiness Directive. The amendment is explicitly limited to correcting a typographical error in Note 2 (changing the FAA AD reference from 2000-03-35 to 2000-02-35). The document states 'There is no change to initial requirements of the AD.' The scope remains exactly as originally intended: addressing oxygen system safety in specific BAe 125 aircraft models."},"complexity_factors":["Multiple aircraft model variants with different service bulletin requirements (5 distinct groups)","Conditional compliance pathway: if-then logic for inspections, cleaning, flow checks, and repairs","Cross-references to external manufacturer service bulletins (SB 35-3169, 35-3171, 35-3034, 35-3170, 35-3167, 35-3168)","Nested requirements with multiple sub-points (1.a, 1.b, 1.c, etc.)","Exception clause (Requirement 5) requiring CASA approval for certain repair methods","Technical aviation terminology requiring specialized knowledge (cadmium plating, cone caps, tee-pieces, flow checks)","Defined term for 'detailed visual inspection' with specific technical meaning"],"plain_english_summary":"This CASA Airworthiness Directive mandates operators of certain BAe 125/Hawker 800/1000 family aircraft to replace and inspect cadmium‑plated oxygen plumbing fittings that can corrode and shed metal particles, risking blockage of emergency oxygen supply. Compliance (replacement/inspection and any necessary repairs or flow checks) is required within six months of the AD — a safety-critical measure to prevent loss of emergency oxygen to crew and passengers."},"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":false,"description":"Amendment 1 only corrects a typographical error in Note 2 (FAA AD reference corrected from 2000-03-35 to 2000-02-35) and does not change the original AD's technical requirements. The original AD's requirements remain in force (Background; 'There is no change to initial requirements of the AD')."},"complexity_factors":["Multiple affected models and several different service bulletins to follow (SB 35-3169, SB 35-3171, SB 35-3034, SB 35-3170, SB 35-3167, SB 35-3168; all dated September 1998) — increases matching work to airframe (Applicability table and Requirement sections).","Multi-step technical requirements: replace fittings, detailed visual inspection, conditional cleaning, oxygen system flow check, and conditional repair — each step triggers next actions (Requirement 1–4, subsections a–c).","Staggered compliance timing: initial replacements required within 6 months, inspection/clean/flow-checks and repairs often 'before further flight', creating urgent follow-up obligations (Compliance section).","Regulatory discretion where SBs direct contacting manufacturer: repairs must follow a method approved by the Manager, Technical Specialists Section, Certification Standards Branch — adds approval step and potential delay (Requirement: contact Manager paragraph).","Inspection standard defined as a 'detailed visual inspection' with specified lighting and aids — raises labour/access burden and possible need for disassembly (Note 1).","Cross-reference to FAA AD and corrected typographical reference in this Amendment (Background and Note 2) — low substantive effect but relevant to traceability of technical guidance."],"plain_english_summary":"This Directive requires replacing cadmium‑plated cone caps/fittings in the oxygen plumbing of specified BAe 125/Hawker models with improved parts, then visually inspecting removed parts and, if corrosion or flaking is found, cleaning, performing an oxygen flow check and repairing as needed under the applicable Raytheon service bulletin. The authority says the change prevents cadmium flaking that could block valves and cut oxygen supply; aircraft owners/operators must fund and schedule the work under the stated time limits (typically within 6 months or before further flight)."}},"importantCases":[],"_links":{"self":"/api/acts/ad-hs-125-161-amdt-1-oxygen-system","history":"/api/acts/ad-hs-125-161-amdt-1-oxygen-system/history","analysis":"/api/acts/ad-hs-125-161-amdt-1-oxygen-system/analysis","conflicts":"/api/acts/ad-hs-125-161-amdt-1-oxygen-system/conflicts","importantCases":"/api/acts/ad-hs-125-161-amdt-1-oxygen-system/important-cases","documents":"/api/acts/ad-hs-125-161-amdt-1-oxygen-system/documents"}}