Overview

The Civil Aviation Regulations 1998, specifically PART 39 - 105, was enacted by the Australian Government to ensure the safety and regulation of civil aviation within Australia. Among the numerous directives, AD/B747/99 addresses a critical issue concerning Boeing 747 Series aeroplanes, particularly focusing on the differential protection current transformers wiring. This directive was introduced to mitigate the risk of a single fault causing the loss of all normal sources of aircraft power, a problem identified during a 747 Safety Assessment. The Australian Government, through the Civil Aviation Safety Authority, aims to enhance aviation safety by enforcing this directive, which mandates actions in accordance with Boeing Service Bulletin 747-24-2154. Compliance with this directive is essential to ensure that wiring modifications are made to prevent potential power loss and maintain the airworthiness of Boeing 747 aircraft.

Scope and Application

The Civil Aviation Regulations 1998, specifically PART 39 - 105, applies to Boeing 747 series aeroplanes through the Civil Aviation Safety Authority (CASA) Schedule of Airworthiness Directives. This legislation mandates specific actions regarding the wiring of differential protection current transformers, aligning with the requirements outlined in the Boeing Service Bulletin 747-24-2154 and referencing FAA AD 91-18-05. The directive applies to all Boeing 747 aeroplanes within the Australian jurisdiction, ensuring compliance prior to 18 March 1992. This requirement stems from a safety assessment which identified the risk of a single fault leading to the loss of all normal aircraft power. To mitigate this risk, the legislation necessitates the re-routing and addition of shielded wiring associated with the differential protection current transformers in the P6 panel. The directive's scope is confined to the specified aerospace equipment and does not extend to other types of aircraft or industries, ensuring that only the relevant entities and conduct are subject to these safety mandates.

Key Provisions

The Civil Aviation Regulations 1998, particularly Part 39 - 105, contain a specific Airworthiness Directive (AD) concerning Boeing 747 series aeroplanes. This directive, AD/B747/99, focuses on the issue of differential protection current transformers and their wiring (Section 39 - 105). It mandates actions in accordance with the Boeing Service Bulletin 747-24-2154 and references FAA AD 91-18-05 for additional context. The directive applies to specific configurations as detailed in the requirement document and demands compliance prior to 18 March 1992. This directive stems from a safety assessment that revealed the potential for a single fault to lead to the loss of all normal sources of aircraft power, necessitating re-routing and adding shielded wiring to the differential protection current transformers located in the P6 panel. Entities governed by this AD, including aircraft operators and maintenance service providers, must ensure compliance with the specified actions. They are required to follow the Boeing Service Bulletin 747-24-2154 and implement the necessary re-routing and shielding of wiring for the differential protection current transformers. This involves meticulous adherence to the outlined procedures to mitigate the identified safety risks effectively. Non-compliance with these directives could result in significant safety hazards, potentially leading to the complete loss of aircraft power. Failure to comply with the provisions of this AD could lead to severe consequences. While the Civil Aviation Regulations do not explicitly detail the penalties for non-compliance within this specific AD, general provisions under the Civil Aviation Act 1988 could apply. Non-compliance with airworthiness directives can result in enforcement actions, including fines, sanctions, or even the grounding of non-compliant aircraft. The potential for civil or criminal liability exists, particularly if non-compliance leads to an accident or incident. Given the critical nature of the safety directive, the consequences of breaching this AD could be severe, impacting both the operator's reputation and the safety of passengers and crew.