AD/PHZL/62 Amdt 4 - Propeller Blade Pilot Tube Bore

Overview

The Civil Aviation Regulations 1998, enacted by the Australian Parliament, were introduced to regulate civil aviation activities within Australia, ensuring the safety and efficiency of air travel. A specific legislative instrument within these regulations, F2006B06221, addresses issues related to airworthiness directives for certain propellers, particularly those made by Hartzell. This legislative instrument targets the problem of in-flight failures caused by blade bore cracks in specific propeller models used on Nord 262 (Frakes conversion) and Shorts SD3-30 aircraft. The policy objective of this directive is to enhance aviation safety by requiring more stringent inspection and replacement protocols for affected propellers, thereby mitigating the risk of in-flight failures and ensuring compliance with safety standards. The Civil Aviation Safety Authority, under the authority granted by the Civil Aviation Act 1988, has mandated that all relevant propellers must adhere to updated inspection and replacement schedules. The directive specifies that propellers fitted with certain blade types must be inspected or replaced at reduced flight cycle intervals to prevent catastrophic failures. This action follows an investigation into a recent in-flight failure, highlighting the urgency and necessity for enhanced safety measures. The requirement for compliance is clear, mandating specific actions by certain dates to ensure the safety of aircraft using these propellers.

Scope and Application

The Civil Aviation Regulations 1998, specifically Part 39 - 107, issued by the Civil Aviation Safety Authority (CASA), applies to all Hartzell HC-B5MP-3A/M10282A(B)+6 propellers installed on Nord 262 (Frakes conversion) aircraft equipped with P&W PT6A-45 series engines, as well as to all Hartzell HC-B5MP-3A/M10282A(B)+6 propellers installed or being installed on Shorts SD3-30 aircraft that have previously operated on a Nord 262 (Frakes Conversion) aircraft. The directive, however, exempts propellers fitted with the 'N' suffix blades, such as M10282AN(B)+6. The scope of this legislation is national, applying to all aircraft within the Commonwealth of Australia. The requirements of this directive include actions to be taken in accordance with Hartzell Service Bulletin No 178 and the replacement of M10282A(B)+6 blades with M10282AN(B)+6 blades. Compliance mandates are set for various flight cycle intervals, and the directive applies to propellers that have operated a specified number of flight cycles since their last inspection. The directive is an amendment to previous regulations, reflecting CASA’s commitment to ensuring aviation safety following an in-flight failure investigation.

Key Provisions

The Civil Aviation Regulations 1998, particularly Part 39 - 107, address the safety directives for aircraft propellers, specifically focusing on Hartzell variable pitch propellers in this case. The regulation (AD/PHZL/62Amdt 4) pertains to the Propeller Blade Pilot Tube Bore, which is applicable to specific Hartzell HC-B5MP-3A/M10282A(B)+6 propellers installed on Nord 262 (Frakes conversion) aircraft and Shorts SD3-30 aircraft that have previously operated on a Nord 262 (Frakes Conversion) aircraft. It is important to note that propellers fitted with the 'N' suffix blades are exempt from this directive (e.g., M10282AN(B)+6). Under this directive, there are two primary requirements: Firstly, for propellers fitted with M10282A(B)+6 blades, compliance with Hartzell Service Bulletin No 178 is mandatory. Secondly, the directive mandates the replacement of M10282A(B)+6 blades with M10282AN(B)+6 blades. The compliance schedule is structured based on the number of flight cycles since the last blade bore inspection. For propellers with fewer than 200 flight cycles since the last inspection, compliance must be achieved before completing 300 flight cycles. For propellers in service with more than 300 flight cycles since the last inspection, compliance must be achieved before completing 350 cycles. For propellers that have operated more than 350 flight cycles since the last inspection, compliance must be achieved before further flight after 15 May 1994. Following this initial compliance, all blade bores must be reinspected at intervals not exceeding 300 flight cycles until the M10282A(B)+6 blades have been replaced with M10282AN(B)+6 blades. The replacement of blades must be completed by 30 June 1994. The obligations imposed by this directive are stringent and clear, demanding immediate action to ensure safety. Operators of Nord 262 (Frakes conversion) aircraft and Shorts SD3-30 aircraft must adhere to the specified inspection and replacement schedules, or risk non-compliance with aviation safety standards. Failure to comply with these directives could result in severe consequences, including grounding of the aircraft until the required actions are taken, and potentially, legal repercussions for non-compliance. Breaching the requirements outlined in this directive can lead to serious civil and criminal consequences. The Civil Aviation Safety Authority (CASA) has the authority to enforce compliance and may take action against non-compliant aircraft operators. Potential penalties include fines, suspension of airworthiness certificates, and other regulatory sanctions. While the specific penalties are not detailed in the text, they could be substantial given the safety-critical nature of the directive. Ensuring adherence to these provisions is critical to maintaining the safety standards required in civil aviation.