AD/BELL 206/14 Amdt 2 - Cyclic Control Bellcrank Supports - Inspection and Replacement

Overview

The Civil Aviation Regulations 1998, enacted by the Parliament of Australia, form a crucial framework governing civil aviation safety and operations within the country. This legislative instrument addresses the need for stringent safety standards and procedures to ensure the safety of aircraft and passengers. One particular aspect covered in PART 39 - 105 of the Civil Aviation Regulations 1998 is the issuance of Airworthiness Directives (ADs) to manage the safety of specific aircraft models. The AD/BELL 206/14 Amendment 2, issued by the Civil Aviation Safety Authority, targets Bell Helicopter Textron Canada (BHTC) 206 and Agusta Bell 206 Series Helicopters, specifically addressing issues related to the cyclic control bellcrank supports. The directive mandates regular inspection and, where necessary, replacement of these components to prevent potential structural failures, thereby ensuring the continued airworthiness and safety of these helicopters. The policy objective behind such regulations is to maintain and enhance the safety standards of civil aviation through proactive and systematic oversight.

Scope and Application

The Civil Aviation Regulations 1998, specifically Part 39 - 105, addresses the safety directives concerning Bell Helicopter Textron Canada (BHTC) 206 and Agusta Bell 206 Series Helicopters. This legislation applies to all models of these helicopters that are equipped with magnesium Cyclic Bellcrank Supports, identified by the part number 206-001-521. The regulations mandate the inspection and replacement of the cyclic control bellcrank supports to ensure the airworthiness of these aircraft. The inspection must be performed at each daily or overnight inspection, and any necessary replacements must be completed within 100 hours of service after the specified date of 29 August 1969, and subsequently at intervals not exceeding 100 hours until the magnesium supports are replaced with new aluminium ones. The directive is comprehensive in its requirement for visual inspections, ensuring the integrity of the support assemblies, and specifies the torque settings for the bolts to maintain secure attachment to the fuselage. Additionally, any cracks or corrosion must be addressed, and the cyclic control rigging must be inspected following the replacement of a support assembly, as outlined in the Model 206A Maintenance and Overhaul Instructions.

Key Provisions

The Civil Aviation Regulations 1998, specifically within Part 39, include the Airworthiness Directives (ADs) that govern the maintenance and safety standards for aircraft in Australian airspace. In relation to Bell Helicopter Textron Canada (BHTC) 206 and Agusta Bell 206 Series helicopters, AD/BELL 206/14 Amendment 2 outlines specific requirements for the inspection and replacement of cyclic control bellcrank supports. This directive applies to all models of these helicopters equipped with magnesium cyclic bellcrank supports (P/N 206-001-521). The directive mandates a thorough inspection and, if necessary, the replacement of the cyclic control bellcrank supports. Operators are required to remove the upper forward cowling to expose the hydraulic power cylinders, and then inspect the attachment of the support assemblies to the fuselage to ensure they are secure. If any support assembly is found to be loose, the NAS 1304-9 bolt must be torqued to 80 to 100 inch pounds, and the NAS 1305-9 bolt to 120 to 145 inch pounds. Visual inspections must be conducted for cracks in the spotfaced areas around the attachment bolts and in the fillet radii between the base and vertical section of the supports, using appropriate lighting. Any nicks or corrosion must be smoothed out using a fine file and crocus cloth. If cracks are detected, the support assembly must be replaced before further flight, and the cyclic control rigging inspected according to the Model 206A Maintenance and Overhaul Instructions. Additionally, the magnesium support assemblies must be replaced with new assemblies. Compliance with these requirements is mandatory. Inspections and replacements as outlined in paragraphs 1 and 2 must be conducted at each daily or overnight inspection, while the replacement of the support assemblies must be completed within 100 hours of time in service after the specified date and at intervals not exceeding 100 hours until replaced with new aluminium support assemblies (P/N 206-00-544). Failure to adhere to these directives can result in significant safety risks, potentially leading to severe consequences for both the aircraft and its occupants. It is imperative that all operators comply with these regulations to ensure the airworthiness and safety of the aircraft in operation.