AD/BAe 146/21 - Remote Controlled Circuit Breaker

Overview

The Civil Aviation Regulations 1998, as amended by the legislative instrument F2006B03474, address the safety concerns associated with the BAe 146 Series aeroplanes by issuing specific airworthiness directives. This regulation was enacted to ensure that all BAe 146 Series aeroplanes adhere to the requirements outlined in BAe Service Bulletin 24-69-70484A, which was mandated by the UK Civil Aviation Authority (CAA) due to an in-service incident. The incident involved an adjustment nut becoming loose within the AC hydraulic pump remote controlled circuit breaker, leading to a failure of the over current protection system. The directive aims to ensure compliance with these safety standards before 6 November 1990, thereby enhancing the overall safety of civil aviation operations.

Scope and Application

The Civil Aviation Regulations 1998, specifically Part 39 - 105 Civil Aviation Safety Authority Schedule of Airworthiness Directives, applies to all BAe 146 Series aeroplanes, mandating compliance with BAe Service Bulletin 24-69-70484A, which has been classified as mandatory by the UK Civil Aviation Authority. This regulation ensures that all operators of BAe 146 Series aeroplanes adhere to the outlined requirements to address an in-service incident where an adjustment nut within the AC hydraulic pump remote controlled circuit breaker came loose, leading to one set of contacts remaining closed and disabling the overcurrent protection. The geographic reach of this regulation is national, as it pertains to all BAe 146 Series aeroplanes operating within Australia, ensuring safety standards are uniformly upheld across the Commonwealth. The directive is applicable to all BAe 146 Series aeroplanes detailed in the requirement document and compliance must be achieved prior to 6 November 1990.

Key Provisions

The Civil Aviation Regulations 1998 (Part 39 - 105) include an Airworthiness Directive (AD) specifically for British Aerospace BAe 146 Series aeroplanes, identified as AD/BAe 146/21, concerning the remote controlled circuit breaker (Section 1). The directive mandates compliance with BAe Service Bulletin 24-69-70484A, a requirement classified as mandatory by the UK Civil Aviation Authority (CAA). This directive applies to all BAe 146 Series aeroplanes specified in the accompanying Requirement document (Section 2). The action required is to follow the instructions detailed in the aforementioned service bulletin to ensure the safety and airworthiness of the aircraft. Operators and owners of BAe 146 Series aeroplanes must ensure compliance with the directive by implementing the actions outlined in the service bulletin. This includes a thorough inspection and, if necessary, adjustment or replacement of the remote controlled circuit breaker to prevent the adjustment nut from coming loose and to ensure that both sets of contacts are functional. The directive necessitates that these actions be taken before 6 November 1990, as specified (Section 3). Failure to adhere to these requirements can lead to serious safety implications, potentially compromising the aircraft's ability to safely operate. The AD imposes specific obligations on the operators and owners of the affected aeroplanes. These include conducting a detailed inspection of the AC hydraulic pump remote controlled circuit breaker, ensuring it conforms to the specifications and recommendations in the BAe Service Bulletin 24-69-70484A. This involves checking for any loose adjustment nuts and securing them appropriately to prevent any future incidents. Additionally, operators must maintain accurate records of the compliance actions taken, as this documentation may be required for future audits or inspections by the Civil Aviation Safety Authority (CASA) (Section 4). Failure to comply with the provisions of this Airworthiness Directive can result in serious consequences. Non-compliance with mandatory airworthiness directives is a criminal offence under Australian law, and violators can face significant penalties. The maximum penalty for contravening the Civil Aviation Regulations can include substantial fines and, in some cases, imprisonment. Furthermore, non-compliance can also lead to the grounding of the affected aircraft until the required actions are completed, which can have significant operational and financial implications for the operators (Section 5).