Overview

The Airworthiness Directive (AD) AD/B727/183, issued under subregulation 39.1(1) of the Civil Aviation Regulations 1998 (CAR 1998), was enacted to address the safety issue of flight crew incapacitation due to lack of oxygen in the event of rapid depressurisation in Boeing 727 series aeroplanes. This AD was issued by the Civil Aviation Safety Authority (CASA) on 3 February 2003 and became effective on 20 March 2003. The directive mandates a revision to the Aircraft Flight Manual (AFM) to specify that flight crew should don their oxygen masks immediately upon hearing the cabin altitude warning horn, rather than waiting for other indications of rapid depressurisation. This change aims to prevent incapacitation of the flight crew, ensuring continued control of the aeroplane and enhancing overall flight safety. The AD was published in the Commonwealth of Australia Gazette on 26 February 2003.

Scope and Application

The Airworthiness Directive (AD) issued under subregulation 39.1 (1) of the Civil Aviation Regulations 1998 applies specifically to Boeing 727 series aeroplanes. This directive mandates the revision of procedures regarding the donning of oxygen masks in the event of rapid depressurisation as outlined in the Aircraft Flight Manual (AFM). The AD specifies that when the cabin altitude warning horn sounds, the flight crew must don oxygen masks immediately, rather than waiting for explicit signs of rapid depressurisation. This change is intended to prevent the incapacitation of the flight crew due to lack of oxygen, which could potentially lead to the loss of control of the aeroplane. The directive is effective from 20 March 2003, with compliance required before 20 June 2003. The directive is applicable across the Commonwealth of Australia and is notified in the Commonwealth of Australia Gazette on 26 February 2003. It should be noted that this AD does not explicitly mention any exclusions, exemptions, or thresholds and relies on the instructions set out within the requirement section for its implementation.

Key Provisions

The Airworthiness Directive (AD/B727/183) issued under subregulation 39.1 (1) of CAR 1998, applies to Boeing 727 series aeroplanes, specifically targeting the procedures for donning oxygen masks during rapid depressurisation (section 3). The directive mandates that the Emergency Procedures section of the Aircraft Flight Manual (AFM) be revised to ensure that flight crews don their oxygen masks immediately upon hearing the cabin altitude warning horn, instead of waiting for the actual rapid depressurisation event (section 3). This change is to be made by inserting a copy of the directive into the relevant section of the AFM, with the specific instruction to modify the text from "RAPID DEPRESSURISATION Oxygen Masks & Regulators—ON, 100% ALL" to "CABIN ALTITUDE WARNING OR RAPID DEPRESSURISATION If the cabin altitude warning horn sounds: Oxygen Masks & Regulators—ON, 100%, ALL" (section 3). Operators of Boeing 727 series aeroplanes must ensure that the AFM is updated in accordance with the directive before 20 June 2003, as the AD became effective on 20 March 2003 (section 3). This obligation is critical to maintaining the airworthiness of the aircraft and ensuring the safety of the flight crew and passengers by preventing incapacitation due to lack of oxygen during a cabin pressure loss event (section 3). Failure to comply with this directive could result in the aeroplane being deemed unairworthy, potentially leading to grounding and severe penalties as per the Civil Aviation Regulations 1998. The AD does not explicitly detail specific offences or penalties for non-compliance within the directive itself, but under the Civil Aviation Regulations 1998, non-compliance with ADs can result in significant civil or criminal penalties. These can include fines, imprisonment, or both, depending on the severity of the non-compliance and its impact on aviation safety (section 3). Operators found in breach of ADs can also face operational restrictions, such as being prohibited from flying the affected aircraft until compliance is achieved.