Overview

The Airworthiness Directive (AD) issued under subregulation 39.1(1) of the Civil Aviation Regulations 1998 (CAR 1998) addresses a critical safety concern related to Boeing 747 series aeroplanes, specifically regarding the procedures for donning oxygen masks during rapid depressurisation. Enacted in 2003 by the Civil Aviation Safety Authority (CASA) as a legislative instrument, the directive was introduced to address the problem of flight crew incapacitation due to lack of oxygen, which could lead to loss of control of the aircraft. The directive mandates the revision of the Aircraft Flight Manual (AFM) to update the procedures, ensuring that flight crews don their oxygen masks immediately upon hearing the cabin altitude warning horn, regardless of the aircraft's altitude. This change aims to enhance safety by preventing potential incapacitation of the flight crew in emergency situations.

Scope and Application

The Airworthiness Directive issued by the Civil Aviation Safety Authority (CASA) under the Civil Aviation Regulations 1998 pertains specifically to Boeing 747 Series Aeroplanes, including models 747-100, 100B, 100B SUD, -200B, -200C, 200F, -300, 747SR, and 747SP. This directive applies to the aircraft within the Australian jurisdiction, as it is issued by a delegate of the Civil Aviation Safety Authority, which is a Commonwealth authority. The AD mandates that the procedures for donning oxygen masks in the event of rapid depressurisation must be revised to ensure flight crew don oxygen masks immediately upon hearing the cabin altitude warning horn, rather than waiting for the aeroplane to reach a specific altitude. This requirement is critical to prevent incapacitation due to lack of oxygen, which could lead to loss of control of the aeroplane. The directive became effective on 20 March 2003, with compliance required before 20 June 2003. The AD does not specify any exclusions or exemptions, and it directly references FAA AD 2003-03-15 Amdt 39-13039, indicating alignment with international safety standards.

Key Provisions

The Airworthiness Directive (AD) applies to Boeing 747 series aeroplanes, specifically models 747-100, 100B, 100B SUD, -200B, -200C, 200F, -300, 747SR, and 747SP (section 3). The directive mandates a revision to the procedures for donning oxygen masks in the event of rapid depressurisation, as detailed in the Emergency Procedures section of the Aircraft Flight Manual (AFM) (section 4). Specifically, it requires the deletion of the current instruction stating "RAPID DEPRESSURISATION (With aeroplane altitude above 14,000 feet MSL.) RECALL Oxygen Masks & Regulators—ON, 100%" and the insertion of the new instruction "CABIN ALTITUDE WARNING OR RAPID DEPRESSURISATION If the cabin altitude warning horn sounds: RECALL Oxygen Masks & Regulators—ON, 100%" (section 4). The rest of the steps under this heading in the AFM remain unchanged. Operators of the specified Boeing 747 series aeroplanes are required to revise their Aircraft Flight Manuals according to the instructions provided in the directive. This revision must be completed before 20 June 2003 (section 6). The directive became effective on 20 March 2003, which means that operators must ensure compliance by the specified deadline. Failure to comply with this Airworthiness Directive may result in civil or criminal consequences. The Civil Aviation Safety Authority (CASA) has the authority to enforce compliance with airworthiness directives, and non-compliance could lead to penalties or legal action. Although specific penalties are not detailed in the directive, such non-compliance could result in fines, enforcement actions, or other civil penalties under the Civil Aviation Act 1988 or criminal charges under the Criminal Code Act 1995, depending on the severity and circumstances of the non-compliance. The directive underscores the importance of adhering to safety procedures to prevent potential incapacitation of the flight crew due to lack of oxygen, which could result in loss of control of the aeroplane.