AD/BELL 206/107 - Main Rotor Mast

Overview

The Civil Aviation Regulations 1998, amended through the legislative instrument F2006B04420, was enacted to address safety concerns specifically related to certain models of Bell Helicopter Textron Canada (BHTC) helicopters. This regulation was introduced to mitigate the risk posed by potential metallurgical imperfections in the main rotor masts of specific Bell 206 Series helicopters, which could compromise the structural integrity and lead to catastrophic failures during flight. The objective of this directive, as set out in the legislative instrument, is to ensure the safety of aviation operations by mandating the removal and replacement of identified rotor masts. The regulation was enacted by the Commonwealth of Australia and is overseen by the Civil Aviation Safety Authority (CASA), ensuring that the aviation industry adheres to stringent safety standards.

Scope and Application

The Civil Aviation Regulations 1998, specifically Part 39 - 105 concerning the Civil Aviation Safety Authority Schedule of Airworthiness Directives, applies to all Model 206A, 206B, 206L, 206L-1 and 206L-3 Bell Helicopter Textron Canada (BHTC) and Agusta Bell 206 Series helicopters that are equipped with main rotor masts bearing part numbers 206-010-332-121 or 206-040-535-105 and that fall within the serial numbers listed in the requirement documents. The directive applies nationally across the Commonwealth of Australia and is overseen by the Civil Aviation Safety Authority. The primary concern addressed by this Airworthiness Directive is the potential for catastrophic failure due to metallurgical imperfections in certain batches of main rotor masts. Operators must ensure compliance by removing from service any affected masts within 25 hours of time in service after 1 June 1987. This requirement is outlined in Bell Alert Service Bulletins 206-87-37 for models 206A and 206B, and Bell Alert Service Bulletin 206L-87-44 for models 206L series. The Federal Aviation Administration (FAA) Telex AD 87-10-11 also references this directive. The application of this Airworthiness Directive is not restricted by any exclusions, exemptions, or thresholds as stated in the legislative instrument.

Key Provisions

The Civil Aviation Regulations 1998 (part 39 - 105) include specific airworthiness directives for certain models of Bell Helicopter Textron Canada (BHTC) and Agusta Bell 206 Series helicopters. Specifically, AD/BELL 206/107 pertains to the main rotor masts of these helicopters (section 1). This directive applies to Model 206A, 206B, 206L, 206L-1, and 206L-3 helicopters equipped with main rotor mast part numbers 206-010-332-121 or 206-040-535-105, and serial numbers specified in the requirement documents (section 2). The primary requirement is to remove from service any main rotor masts that are identified as defective in the Bell Alert Service Bulletins 206-87-37 for models 206A and 206B, and Bell Alert Service Bulletin 206L-87-44 for models 206L series (section 3). This action must be taken within 25 hours of the helicopters' time in service after 1 June 1987 (section 4). The obligations under this directive are clear and demand immediate action from operators and owners of the specified helicopters. They must identify whether their aircraft is affected by the directive and consult the relevant service bulletins to determine if any main rotor masts need to be removed from service (section 5). They must ensure that the removal is completed within the specified timeframe, which is 25 hours of time in service after the date of the directive, to maintain compliance with airworthiness standards (section 6). Additionally, operators must keep records of any actions taken in accordance with the directive, including documentation of mast removals and compliance checks (section 7). Failure to comply with the airworthiness directive can result in severe consequences. Operators who do not adhere to the requirement to remove defective main rotor masts from service risk facing enforcement actions by the Civil Aviation Safety Authority (CASA) (section 8). The potential penalties for non-compliance can include fines, operational restrictions, or other regulatory measures deemed appropriate by CASA to ensure the safety of the aircraft and its occupants (section 9). The severity of the penalties can vary based on the extent of non-compliance and the impact on aviation safety (section 10). In cases where non-compliance leads to an accident or incident, the consequences can be even more severe, potentially resulting in criminal charges and substantial penalties (section 11).