Overview

The Civil Aviation Safety Authority (CASA) introduced the Airworthiness Directive (AD) AD/B747/313 on 30 September 2004, to address safety concerns associated with the installation of specific fire extinguisher bottles on Boeing 747 series aeroplanes. This legislative instrument was enacted under the Civil Aviation Safety Regulations 1998 (CASR 1998) and was issued by a CASA delegate to correct an unsafe condition related to the potential for fractured discharge heads in fire extinguisher bottles, which could lead to uncontrolled fires. The directive applies to several models of Boeing 747 aeroplanes and mandates inspections and replacements of certain fire extinguisher bottles to mitigate the identified risk. The policy objective of this directive is to ensure the airworthiness of the specified aircraft by preventing potential fire hazards that could compromise the safety of the aeroplane and its occupants.

Scope and Application

The Airworthiness Directive issued under subregulation 39.1 (1) of the Civil Aviation Safety Regulations 1998 pertains specifically to certain models of Boeing 747 aeroplanes, namely the 747-100, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 747-400D, 747-400F, and 747 SR series. The directive mandates an inspection and potentially the replacement of fire extinguisher bottles within these aircraft to rectify an unsafe condition that could lead to fractured discharge heads, leaks of fire-extinguishing agents, and consequently, uncontrolled fires in the engine or Auxiliary Power Unit (APU) that could spread to critical aircraft structures. This AD applies to aeroplanes within the Australian jurisdiction, as it was issued by a delegate of the Civil Aviation Safety Authority (CASA). The directive became effective on 30 September 2004, with specific compliance timelines: inspections must be completed within two years of the directive’s effective date, replacements must occur before further flight if required, and the prohibition on installing certain Kidde Aerospace fire extinguisher bottles must be adhered to immediately upon the directive’s issuance. The directive was published in the Commonwealth of Australia Gazette on 8 September 2004.

Key Provisions

This Airworthiness Directive (AD), issued under subregulation 39.1(1) of the Civil Aviation Safety Regulations 1998, pertains to specific Boeing 747 series aeroplanes and mandates corrective actions to address an unsafe condition related to fire extinguisher bottles in the engine and auxiliary power unit (APU). The AD applies to Boeing Model 747-100, 747-200B, 747-200C, 747-200F, 747-300, 747-400, 747-400D, 747-400F, and 747 SR series aeroplanes as listed in Boeing Alert Service Bulletin 747-26A2272, dated 16 January 2003 (section 1(a)). The directive includes two primary requirements: first, an inspection to determine the part number (P/N) of the fire extinguisher bottles using the Accomplishment Instructions from Boeing Alert Service Bulletin 747-26A2272 (section 1(b)). If neither the "Pre SB A820400-26-432" nor the "Pre SB A830800-26-433" P/Ns listed in Kidde Aerospace Service Bulletins A820400-26-432 and A830800-26-433, respectively, are found installed, no further action is necessary. However, if any of these P/Ns are found, the fire extinguisher bottle must be replaced with a new one having the "Post SB" P/N listed in the applicable Kidde Aerospace service bulletin in accordance with Boeing Alert Service Bulletin 747-26A2272. Second, no aeroplane should be fitted with a Kidde Aerospace fire extinguisher bottle bearing any "Pre SB A820400-26-432" or "Pre SB A830800-26-433" P/N (section 1(b)(ii)). The AD imposes specific obligations on the entities it governs. For Requirement 1(a), the inspection must be completed within two years from the effective date of the AD, which is 30 September 2004 (section 2(a)). For Requirement 1(b), any replacement of fire extinguisher bottles must be completed before further flight (section 2(b)). Requirement 2, prohibiting the installation of certain Kidde Aerospace fire extinguisher bottles, must be adhered to immediately upon the AD's effective date (section 2(c)). Compliance with these requirements ensures the safety of the aircraft by preventing potential issues such as fractured discharge heads, which could lead to leaks, uncontrolled fires, and subsequent damage to the aircraft structure. Failure to comply with the provisions of this AD can result in serious safety risks, as the directive is designed to prevent potentially catastrophic outcomes such as engine or APU fires spreading to critical aircraft components. While the AD itself does not explicitly state specific penalties for non-compliance, non-compliance with airworthiness directives in general can lead to enforcement actions under the Civil Aviation Safety Regulations 1998. Such actions can include fines, enforcement notices, and other regulatory measures to ensure compliance. The severity of penalties can vary based on the nature and extent of the non-compliance, but the overarching aim is to ensure that all safety directives are strictly followed to maintain the highest safety standards in aviation.