AD/SF340/67 - Nose Wheel Hub Heat Treatment

Overview

The Civil Aviation Regulations 1998, specifically in Part 39 - 105, address the safety and airworthiness of aircraft through a series of directives. One such directive, AD/SF340/67, pertains to the nose wheel hub heat treatment for SAAB SF340 series aeroplanes, serial numbers ranging from SF340A-004 through -159 and 340B-160 through -451. This directive was introduced to address the issue identified by the manufacturer, SAAB, regarding certain nose wheel hubs that were inadequately heat-treated, leading to decreased strength and potential safety risks. The directive aims to ensure compliance by requiring action in accordance with SAAB Aircraft Service Bulletin 340-32-116 Revision 1, with the compliance deadline set before 5 February 1999. This legislation is enacted by the Australian Government to maintain the highest standards of aviation safety, ensuring that aircraft meet the necessary safety requirements as stipulated by the Civil Aviation Safety Authority. The policy objective behind AD/SF340/67 is to mitigate the risk associated with inadequately heat-treated nose wheel hubs, which could lead to structural weaknesses and safety hazards. By issuing this airworthiness directive, the Civil Aviation Safety Authority ensures that the affected aircraft are brought into compliance with safety standards, thereby safeguarding the integrity of the aircraft and the safety of those on board. This directive exemplifies the commitment of the Australian Government to enforcing rigorous safety regulations in the aviation industry, ensuring that all aircraft operating within Australian airspace adhere to stringent safety requirements.

Scope and Application

The Civil Aviation Regulations 1998, specifically Part 39 - 105, applies to the Saab SF340 series aeroplanes, with the Airworthiness Directive AD/SF340/67 targeting Saab SF340A aircraft with serial numbers ranging from SF340A-004 to -159 and Saab SF340B aircraft with serial numbers from 340B-160 to -451. This directive mandates adherence to the action outlined in Saab Aircraft Service Bulletin 340-32-116 Revision 1 and refers to LFV AD 1-134 for additional guidance. The directive's purpose is to address a manufacturing defect where certain nose wheel hub castings were inadequately heat-treated, compromising their structural integrity and necessitating their removal to prevent potential bearing cup issues and reduced fatigue life. Compliance with this directive is mandatory, with the requirement to complete the specified actions before 5 February 1999, following the directive's effective date of 28 January 1999. This regulation applies nationally within the Commonwealth of Australia, administered by the Civil Aviation Safety Authority.

Key Provisions

The Civil Aviation Regulations 1998, Part 39 - 105, specifically addresses the SAAB SF340 Series Aeroplanes through Airworthiness Directive AD/SF340/67 (1999). This directive applies to SAAB SF340A aeroplanes with serial numbers SF340A-004 through -159, and SAAB 340B aeroplanes with serial numbers 340B-160 through -451 (Section 1). The directive mandates that action be taken in accordance with SAAB Aircraft Service Bulletin 340-32-116 Revision 1, and references LFV AD 1-134 for additional information. The directive requires compliance unless the specified action has already been completed before 5 February 1999 (Section 2). This directive came into effect on 28 January 1999. The primary obligation imposed by this Airworthiness Directive is that the specified SAAB SF340A and 340B aeroplanes must undergo the corrective action detailed in SAAB Aircraft Service Bulletin 340-32-116 Revision 1. This involves a special heat treatment process for the nose wheel hubs to address issues arising from improper heat treatment during manufacturing. The directive mandates that this corrective action be completed by the specified deadline to ensure the airworthiness and safety of the affected aircraft. Failure to comply with this Airworthiness Directive can have serious ramifications. The Civil Aviation Safety Authority (CASA) may take enforcement action against operators who do not adhere to the requirements set out in this directive. Non-compliance could potentially lead to grounding of the affected aircraft, as the directive is intended to address safety concerns related to the structural integrity of the nose wheel hubs. The potential consequences for non-compliance include both civil and criminal penalties, with the severity of the penalty depending on the extent of non-compliance and any resulting safety incidents. In summary, Airworthiness Directive AD/SF340/67 mandates specific actions to be taken on SAAB SF340 Series aeroplanes to address issues related to the nose wheel hub heat treatment. Operators of these aircraft are required to comply with the directive by adhering to the specified corrective actions and timelines. Failure to comply with this directive could result in enforcement actions by CASA, including potential grounding of the aircraft and civil or criminal penalties.