AD/PA-23/42 Amdt 1 - Alternator Field Fuse - Installation

Overview

The Civil Aviation Regulations 1998, specifically amended in 2006, were enacted to ensure the safety and reliability of civil aviation operations within Australia. One particular legislative instrument, F2006B05468, addresses a critical safety issue concerning the Piper PA-23 (Apache and Aztec) Series Aeroplanes. The problem this legislation targets is the risk of electrical failures in the alternator systems of specific model aircraft, which could potentially lead to in-flight emergencies. The instrument mandates the installation of specific fuses in the alternator field circuits to mitigate these risks. The Civil Aviation Safety Authority, operating under the authority of the Australian Parliament, issued this directive to ensure compliance with safety standards and to protect the lives of passengers and crew on board. This legislative instrument, part of the broader framework established by the Civil Aviation Regulations 1998, reflects the policy objective of maintaining the highest safety standards in civil aviation. By mandating the installation of 3 amp fuses in specified aircraft models, the regulation aims to prevent electrical failures that could compromise the safety of flights. Compliance with these directives is required immediately, underscoring the urgency and importance of these safety measures.

Scope and Application

The Civil Aviation Regulations 1998, specifically Part 39 - 105 under the Civil Aviation Safety Authority Schedule of Airworthiness Directives, applies to the Piper PA-23 (Apache and Aztec) series aeroplanes. The regulations mandate specific modifications and checks for certain serial numbers of these aircraft to ensure airworthiness and safety. The directive applies to aircraft with serial numbers falling within the specified range, namely PA-23-250 with serial numbers 27-2505 and subsequent, provided they are equipped with a voltage regulator selector switch. The directive requires the installation of a 3 amp fuse in specific field circuits of the aircraft's alternator system, depending on the serial number range, and mandates a functional check of the alternator system and voltage regulators as per the manufacturer's service manual. Compliance with these requirements is mandated forthwith. The scope of this legislation is confined to the specified models and serial numbers of the Piper PA-23 series aeroplanes, and it does not extend to other aircraft types or models.

Key Provisions

The Civil Aviation Regulations 1998, specifically Part 39, Section 105, mandate the installation of a 3 amp fuse in certain Piper PA-23 (Apache and Aztec) series aeroplanes. This requirement is outlined in the Airworthiness Directive (AD) AD/PA-23/42 Amendment 1. The directive applies to model PA-23-250 with serial numbers 27-2505 and onwards that are fitted with a voltage regulator selector switch (Section 1). The installation of the fuse must be performed in the field circuit between the “F” field terminal on the alternator and either the alternator main circuit breaker or the voltage regulator selector switch, depending on the aircraft's serial number (Section 2). Aircraft with serial numbers ranging from 27-2505 to 27-3836, and from 27-3838 to 27-3943, must have the fuse installed between the “F” field terminal and the alternator main circuit breaker in cables PF5 and PF11. For aircraft with serial numbers 27-3837 and from 27-3944 onwards, the fuse must be installed between the “F” field terminal and the voltage regulator selector switch in cables PF17A and PF18A. Furthermore, it is essential to functionally check the alternator system and adjust the voltage regulators according to the manufacturer's service manual (Section 2, Note). Compliance with these directives must be achieved forthwith (Section 3). The obligations imposed by these regulations are clear and specific. Aircraft operators and maintenance personnel must ensure that the designated Piper PA-23 series aeroplanes are fitted with the specified fuses as per the serial number ranges provided. The installation must be carried out in accordance with the directive, which includes the precise placement of the fuses within the aircraft’s electrical system. Additionally, a functional check of the alternator system and the adjustment of the voltage regulators must be performed as per the manufacturer's service manual. These obligations are intended to enhance the safety and airworthiness of the aircraft by mitigating risks associated with the alternator field circuits. Failure to comply with the AD/PA-23/42 Amendment 1 can result in significant consequences. While the Civil Aviation Regulations 1998 do not explicitly state penalties for non-compliance in this particular section, general provisions within the Civil Aviation Act 1988 could apply. These may include administrative penalties, enforcement actions, and potential grounding of the non-compliant aircraft. Furthermore, non-compliance could lead to safety issues, thereby increasing the risk of accidents or incidents, which could have severe legal and financial repercussions for the operators and maintenance providers. Ensuring adherence to these directives is therefore crucial to maintain compliance with aviation safety standards and avoid potential legal and operational consequences.