{"id":"F2005L03552","name":"AD/B737/255 - Oxygen Masks AFM Amendment","slug":"ad-b737-255-oxygen-masks-afm-amendment","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":39071,"registerId":"commonwealth-F2005L03552-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Boeing 737 Series Aeroplanes","sectionType":"division","heading":"Boeing 737 Series Aeroplanes","content":"### Boeing 737 Series Aeroplanes\n\n| AD/B737/255 | Oxygen Masks AFM Amendment | 13/2005 |\n| ----------- | -------------------------- | ------- |\n\n| Applicability: | Model 737-100, -200 and -200C series aeroplanes.                                                                                                                                                                               |\n| -------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |\n| Requirement:   | If not previously accomplished, revise the procedures regarding donning oxygen masks in the event of rapid depressurisation, as contained in the Emergency Procedures section of the Aircraft Flight Manual (AFM), as follows: |\n|                | Delete: -                                                                                                                                                                                                                      |\n|                | ''RAPID DEPRESSURISATION (With aeroplane altitude above 14,000 feet MSL)PRIMARYOxygen Masks & Regulators—ON, 100%''                                                                                                            |\n|                | Insert: -                                                                                                                                                                                                                      |\n|                | \"CABIN ALTITUDE WARNING OR RAPID DEPRESSURISATIONIf the cabin altitude warning horn sounds:PRIMARYOxygen Masks & Regulators—ON, 100%\"                                                                                          |\n|                | The rest of the steps under this heading in the AFM are unchanged.The AFM revision may be accomplished by inserting a copy of the Directive into the relevant section of the AFM.                                              |\n|                | Note: FAA AD 2003-03-15 R1 Amdt 39-13366 refers.                                                                                                                                                                               |\n| Compliance:    | Within 90 days after the effective date of this Directive.                                                                                                                                                                     |\n|                | This Airworthiness Directive becomes effective on 22 December 2005.                                                                                                                                                            |\n\n| Background: | This Directive requires the revision of the AFM to advise the flight crew to don oxygen masks as a first and immediate step when the cabin altitude warning horn sounds. This action is necessary to prevent incapacitation of the flight crew due to lack of oxygen, which could result in loss of control of the aeroplane. |\n| ----------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n\n![](image.001.png)  \nJames Coyne  \nDelegate of the Civil Aviation Safety Authority\n\n10 November 2005","sortOrder":0},{"sectionNumber":"AD/B737/255","sectionType":"part","heading":"AD/B737/255","content":"## AD/B737/255","sortOrder":1},{"sectionNumber":"Oxygen Masks AFM Amendment","sectionType":"part","heading":"Oxygen Masks AFM Amendment","content":"## Oxygen Masks AFM Amendment","sortOrder":2},{"sectionNumber":"13/2005","sectionType":"part","heading":"13/2005","content":"## 13/2005","sortOrder":3}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"The Directive replaces an altitude‑based instruction (‘rapid depressurisation with aeroplane altitude above 14,000 feet MSL’) with a trigger tied to the cabin altitude warning horn or rapid depressurisation, thus broadening the immediate donning requirement to any situation where the cabin altitude warning horn sounds. This alters the operational trigger for mask donning and requires AFM text replacement (Requirement; Background)."},"complexity_factors":["Narrow fleet applicability: only Boeing 737-100, -200 and -200C models (Applicability)","Single, discrete procedural change to AFM wording (Requirement)","Clear compliance deadline of 90 days and simple method for amendment (Compliance)","Safety-critical operational effect: changes when crew must don oxygen masks (Requirement; Background)","Low regulatory discretion—directive prescribes specific AFM text (Requirement)","Cross-reference to FAA AD may require alignment with prior foreign AD (Requirement note)"],"plain_english_summary":"This Directive requires operators of Boeing 737-100, -200 and -200C aeroplanes to revise the Aircraft Flight Manual emergency procedures so flight crew don oxygen masks immediately when the cabin altitude warning horn sounds, replacing the prior “rapid depressurisation above 14,000 ft” wording (Requirement; Applicability). Operators must complete the AFM revision within 90 days (Compliance); the immediate costs are updating the manual (can be done by inserting the Directive) and ensuring crews follow the new donning step (Background)."},"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 Airworthiness Directive maintains its original narrow scope. It addresses a specific safety-critical procedural change for a defined subset of aircraft. There is no evidence of scope creep; the directive does not expand beyond its original purpose of mandating an immediate oxygen mask procedure change."},"complexity_factors":["Single, specific operational requirement (one procedure change)","No defined terms section or interpretation provisions","Minimal conditional logic (only applicability criteria: specific aircraft models)","No cross-references to other legislation (only a non-binding note referencing the related FAA directive)","Straightforward compliance mechanism (insert page into manual or formal revision)","Short document (approximately 300 words of substantive content)"],"plain_english_summary":"This CASA Airworthiness Directive requires operators of Boeing 737-100, -200 and -200C aircraft to revise flight manual emergency procedures so pilots immediately don oxygen masks whenever the cabin altitude warning horn sounds. \n\nIt removes reliance on judging “rapid” depressurisation or altitude, closing a hypoxia risk. Operators must comply within 90 days of 22 December 2005."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b737-255-oxygen-masks-afm-amendment","history":"/api/acts/ad-b737-255-oxygen-masks-afm-amendment/history","analysis":"/api/acts/ad-b737-255-oxygen-masks-afm-amendment/analysis","conflicts":"/api/acts/ad-b737-255-oxygen-masks-afm-amendment/conflicts","importantCases":"/api/acts/ad-b737-255-oxygen-masks-afm-amendment/important-cases","documents":"/api/acts/ad-b737-255-oxygen-masks-afm-amendment/documents"}}