AD/BELL 206/137 - Fuel Drain Tubes

Overview

The Civil Aviation Regulations 1998, as amended, were enacted to ensure the safety and regulation of civil aviation within Australia. A key aspect of this regulation is the Civil Aviation Safety Authority's (CASA) issuance of Airworthiness Directives (ADs) to address specific safety concerns in aircraft. AD/BELL 206/137, introduced on 9 September 1996, specifically targets the Bell Helicopter Textron Canada (BHTC) 206 and Agusta Bell 206 series helicopters to mitigate the risk of fuel migrating into critical components during fuel filter drainage. This directive aims to prevent potential fire hazards by ensuring that fuel is not forced upwards into the fuel pump seal or starter generator seal, a problem identified through reports of fuel migration during maintenance operations. The policy objective is to maintain the airworthiness of these aircraft by enforcing necessary modifications as detailed in the referenced service bulletins and Transport Canada directives.

Scope and Application

The Civil Aviation Safety Authority Schedule of Airworthiness Directives under the Civil Aviation Regulations 1998 applies specifically to certain Bell Helicopter Textron Canada (BHTC) and Agusta Bell 206 series helicopters. This regulation targets particular models and serial numbers of the Bell 206L-1, 206L-3, and 206L-4 helicopters, which are required to adhere to the directive concerning fuel drain tubes to mitigate fire hazards. The requirement stipulates that the fuel drain tubes must be reworked according to Bell Alert Service Bulletin 206L-96-103 Revision A dated 25 March 1996, with compliance expected unless this has already been completed. This directive is critical for the safety of these aircraft, as it directly addresses the potential for fuel to migrate upwards into the fuel pump seal or starter generator seal during airframe fuel filter drainage, which could otherwise result in a fire hazard. The directive is applicable within the Commonwealth of Australia and is enforced to ensure adherence to safety standards by the specified helicopter models and serial numbers.

Key Provisions

The Civil Aviation Regulations 1998, under Part 39 - 105, specifically address the airworthiness directives for certain Bell Helicopter Textron Canada (BHTC) models, particularly the Bell 206 and Agusta Bell 206 series helicopters. The regulation AD/BELL 206/137 (section 9/96) focuses on fuel drain tube modifications to mitigate a specific safety risk. This regulation applies to certain serial numbers of the Bell 206L-1, 206L-3, and 206L-4 models (sections 206L-1 S/N 45154 to 45790, 206L-3 S/N 51001 to 51612, and 206L-4 S/N 52001 to 52158). The directive mandates that the fuel drain tubes must be reworked to prevent fuel from being forced upwards into the fuel pump seal or starter generator seal during airframe fuel filter drainage, as detailed in Bell Alert Service Bulletin 206L-96-103 Revision A dated 25 March 1996. This rework is essential to avoid a potential fire hazard that could arise from fuel migration. The obligations imposed by this directive are quite clear and specific. Owners or operators of the affected Bell 206 series helicopters must ensure that the rework on the fuel drain tubes is completed. This compliance must be achieved prior to 30 October 1996, unless the modification has already been performed. The requirement is straightforward: follow the detailed instructions provided in the Bell Alert Service Bulletin 206L-96-103 Revision A, which includes specific technical procedures to safely and effectively modify the fuel drain tubes. This directive aims to address a known safety concern that could compromise the integrity of the fuel system and potentially lead to catastrophic failures. Failure to comply with the AD/BELL 206/137 directive could result in serious consequences. While the Civil Aviation Regulations do not explicitly detail penalties for non-compliance in this particular directive, general aviation regulations usually impose severe penalties for non-compliance with airworthiness directives. These can include fines, potential grounding of the aircraft, and other administrative actions that could impact the operational status of the helicopter. The overarching goal of these regulations is to ensure the highest standards of safety in civil aviation, and non-compliance could lead to serious safety risks, including the possibility of aircraft accidents or incidents. The potential for civil or criminal liability also exists if non-compliance results in harm or damage.