AD/EMB-110/50 - Automatic Propeller Feathering System

Overview

The Civil Aviation Regulations 1998, as amended, were enacted to ensure the safety of civil aviation within Australia. This legislation, overseen by the Australian Parliament, aims to regulate and maintain high safety standards in the aviation industry. The specific legislative instrument F2006B09491, which pertains to the Embraer EMB-110 (Bandeirante) Series Aeroplanes, was introduced to address the issue of a malfunction in the automatic propeller feathering system. This problem was identified through reports of hidden failure modes in the system, which could lead to unsafe operational conditions. The policy objective of this directive is to mandate inspections of the control and test switch of the automatic propeller feathering system to ensure early detection and mitigation of such failures, thereby enhancing flight safety. Compliance with this directive is essential for all EMB-110 aircraft to operate within Australian airspace.

Scope and Application

The Embraer EMB-110 Series Aeroplanes Automatic Propeller Feathering System Airworthiness Directive (AD) issued by the Civil Aviation Safety Authority under the Civil Aviation Regulations 1998, applies specifically to all EMB-110 aircraft. The directive mandates that the control and test switch of the automatic propeller feathering system must be inspected in accordance with Embraer Service Bulletin 110-61-0032, dated 6 October 1995. This inspection must be carried out unless it has already been performed, within 50 hours of the aircraft being in service after 17 November 1995. This directive is a direct response to a reported malfunction in the automatic feathering mechanism of the EMB-110 propeller, which was traced to a hidden failure mode involving a loss of electrical connection between the control and test switch pins and the wires soldered to them. This failure mode was not detected by the preflight feathering test, necessitating the directive to ensure early detection and rectification of this issue.

Key Provisions

The Civil Aviation Regulations 1998, Part 39 - 105 (subsections) specifically addresses airworthiness directives concerning various aircraft types, including the Embraer EMB-110 (Bandeirante) series aeroplanes. The regulation AD/EMB-110/50 mandates inspections of the automatic propeller feathering system's control and test switch (section 1). This directive applies to all EMB-110 aircraft and necessitates that the inspection be performed in accordance with Embraer Service Bulletin 110-61-0032 dated 6 October 1995 (section 2). A reference to a related directive issued by the Brazilian Civil Aviation Authority (CTA) is also provided (section 3). The compliance requirement states that unless the inspection has already been completed, it must be performed within 50 hours of the aircraft being in service after 17 November 1995 (section 4). The directive aims to detect a specific failure mode related to the electrical connection between the control and test switch pins and the wires soldered to them, which was identified through an investigation into a reported malfunction of the automatic feathering mechanism (section 5). The Civil Aviation Regulations 1998 impose several obligations on the operators of EMB-110 series aeroplanes. Primarily, operators must ensure that the automatic propeller feathering system's control and test switch is inspected according to the specified Embraer Service Bulletin (section 2). This inspection must be completed within 50 hours of the aircraft being in service after the directive's effective date of 17 November 1995, unless it has already been performed (section 4). Failure to comply with this requirement can lead to potential safety issues, as the directive was issued to address a previously unidentified failure mode that could compromise the integrity of the feathering mechanism (section 5). Additionally, operators must maintain records of the inspections performed to demonstrate compliance with the regulation (section 6). Breaching the provisions of this airworthiness directive may result in various consequences. While specific penalties are not detailed in the regulation, non-compliance with airworthiness directives is generally considered a serious matter under civil aviation law. Potential consequences may include administrative actions by the Civil Aviation Safety Authority (CASA), such as fines, suspension or revocation of the aircraft's airworthiness certificate, and possible criminal charges if the non-compliance leads to an accident or endangers safety. The maximum penalties for such breaches can be substantial, depending on the severity of the non-compliance and any resulting harm (section 7). It is important for operators to adhere strictly to the directive to avoid these potential repercussions.