AD/DHC-6/22 - Propeller Auto Feather System - Modification

Overview

The Civil Aviation Regulations 1998, enacted by the Parliament of the Commonwealth of Australia, were established to ensure the safety and efficiency of civil aviation within Australia. This comprehensive set of regulations includes the Airworthiness Directives, which are legally binding instructions issued by the Civil Aviation Safety Authority (CASA) to address safety issues identified in specific aircraft types. The problem these regulations aim to address is the maintenance of airworthiness standards to prevent accidents and ensure the safety of passengers and crew. Policy objectives include enforcing mandatory safety standards, ensuring compliance with international aviation safety requirements, and maintaining public confidence in the safety of air travel. One specific example of an Airworthiness Directive is AD/DHC-6/22, which pertains to the propeller auto-feather system modification for DHC-6 (Twin Otter) series aeroplanes. This directive was introduced to rectify a known safety issue and applies to a defined series of aircraft serial numbers. The directive requires compliance by a specific date, ensuring that the identified safety concerns are addressed promptly to mitigate risks associated with the affected aircraft.

Scope and Application

The Civil Aviation Regulations 1998, specifically Part 39 - 105, addresses the application of the Civil Aviation Safety Authority's (CASA) Schedule of Airworthiness Directives for DHC-6 (Twin Otter) series aeroplanes, providing critical safety instructions pertinent to the aircraft's operation. This particular directive, AD/DHC-6/22, pertains to the propeller auto feather system modification and applies to aircraft with specific serial numbers, including those within the ranges of 210, 231, 232, 234-245, 247-250, 252-256, 259-261, 264, 265, 267, 269-273, and 275 to 277. The directive mandates compliance before 1 September 1970, referencing De Havilland of Canada Service Bulletin No. 6/236. The regulation applies to the specified aircraft, ensuring they meet the necessary safety standards through modifications, thereby affecting the entities that own and operate these aircraft within Australia's jurisdiction. The regulation's scope is explicitly defined by the serial numbers of the aircraft it targets, and any deviation from the specified compliance date could result in non-compliance with CASA standards.

Key Provisions

The main operative sections of AD/DHC-6/22, as contained within the Civil Aviation Regulations 1998, concern the modification of the propeller auto feather system on DHC-6 (Twin Otter) Series aeroplanes. Specifically, the directive applies to aircraft with serial numbers 210, 231, 232, 234-245, 247-250, 252-256, 259-261, 264, 265, 267, 269-273, and 275 to 277 (section 1). Compliance with these requirements must be achieved before 1 September 1970, as referenced in the directive. The Act imposes several obligations on the parties and entities it governs. Aircraft owners, operators, and maintenance providers must ensure that the specified modifications to the propeller auto feather system are implemented as outlined in De Havilland of Canada Service Bulletin No. 6/236 (section 2). This includes conducting the necessary inspections, repairs, or replacements to meet the airworthiness standards set forth in the directive. Failure to comply with the requirements of AD/DHC-6/22 may result in civil or criminal consequences. Under section 91 of the Civil Aviation Act 1988, any person who contravenes a direction issued under the Civil Aviation Regulations 1998 may be liable for a civil penalty. The maximum penalty for such an offence is specified in section 85 of the Act, which can amount to significant financial sanctions for non-compliance. Additionally, in cases where the breach leads to a safety incident, further criminal charges may be pursued against the responsible parties, potentially leading to imprisonment or heavier fines as determined by the court.