AD/SV4/1 Amdt 1 - Lower Mainplane Centre Section Tie Rods

Overview

The Civil Aviation Regulations 1998, administered by the Civil Aviation Safety Authority (CASA), are the principal regulations governing aviation safety in Australia. One of the key components of these regulations is Part 39, which includes the Schedule of Airworthiness Directives. This particular legislative instrument, F2006B07155, pertains to the Stampe SV4 Series Aeroplanes and specifically addresses safety concerns related to the lower mainplane centre section tie rods. The directive was enacted to address a critical safety issue identified in the UK, where a fatal accident was caused by fatigue failure of the tie rods. The policy objective of this directive is to ensure the safety and airworthiness of Stampe SV4 Series Aeroplanes by mandating rigorous inspection and replacement protocols for the tie rods to prevent similar incidents in Australia. The enactment of this directive by CASA aims to rectify a significant gap in aviation safety by focusing on the condition of the lower mainplane centre section tie rods. The directive requires all models of Stampe SV4 Series Aeroplanes to undergo specific inspections and, where necessary, retire the tie rods from service to prevent fatigue failure. By setting forth stringent compliance requirements, including the inspection of tie rod threads for wear and damage, and mandating the replacement of tie rods that do not meet specified standards, the directive seeks to enhance the overall safety of aviation operations involving these aircraft.

Scope and Application

The Civil Aviation Regulations 1998, specifically PART 39 - 105 under the Civil Aviation Safety Authority (CASA) Schedule of Airworthiness Directives, applies to all models of Stampe SV4 Series Aeroplanes. This regulation mandates inspections and actions concerning the lower mainplane centre section tie rods to ensure safety and compliance with airworthiness standards. The directive applies to all aircraft of this model and mandates inspections and specific actions for the tie rods to prevent fatigue failure, following a fatal accident in the UK. For Requirement 1, tie rods with over 100 hours of service time must be inspected before further flight after 25 April 1988. Compliance for Requirement 2 stipulates that tie rods meeting specific standards must be retired before exceeding 500 hours of component time in service, while those not meeting these standards or showing signs of wear or damage must be replaced before further flight. Additionally, tie rods must be installed and tightened following precise instructions, with a specific prohibition on using spring washers. The directive extends its applicability nationally, impacting all operators and entities within the Commonwealth of Australia who possess or operate Stampe SV4 Series Aeroplanes. The regulation does not explicitly state exclusions or exemptions, but compliance is mandatory for the specified models and components.

Key Provisions

The Civil Aviation Regulations 1998, specifically under PART 39 - 105, includes a Schedule of Airworthiness Directives which governs the maintenance and operation of aircraft. In this case, the focus is on the Stampe SV4 Series Aeroplanes, with AD/SV4/1 Amendment 1 detailing the requirements for the lower mainplane centre section tie rods (Section 1). The directive applies to all models of the Stampe SV4 Series Aeroplanes (Section 2). The primary requirement is to inspect the lower mainplane centre section tie rods to determine their type and assess their condition, wear, and damage (Section 3(1)). After inspection, the tie rods must be retired from service in accordance with specific conditions (Section 3(2)). For Requirement 1, tie rods that have exceeded 100 hours of service time must be inspected before further flight after 25 April 1988 (Section 3(2)(a)). For Requirement 2, tie rods must comply with certain standards and conditions before exceeding specified component time in service, or they must be replaced if they do not meet these criteria (Section 3(2)(b) and (c)). The obligations imposed by these directives require meticulous attention to the maintenance of the tie rods. Specifically, operators of Stampe SV4 Series Aeroplanes must ensure that tie rods are inspected according to the specified timeframes and conditions. Tie rods must be identified as compliant with certain standards, such as those specified in Aerospatiale Service Bulletin Stampe No 1 or the modifications by Rollason Aircraft and Engines Ltd, and their threads must be in good condition (Section 3(2)(a)). If the tie rods do not meet these standards or show signs of wear or damage, they must be replaced before the aircraft can be flown again (Section 3(2)(c)). Additionally, tie rods must be installed and tightened according to the instructions provided in Aerospatiale Service Bulletin Stampe No 1, and spring washers must not be used if washers are used under the nuts (Section 4). Failure to comply with the requirements of these directives can result in serious consequences. The directives are grounded in safety, following a fatal accident in the UK caused by fatigue failure of the tie rods. Non-compliance could lead to the grounding of the aircraft until the tie rods are properly inspected and any necessary replacements are made. The regulations are clear that tie rods must be retired from service if they do not meet the specified conditions, and any failure to do so could result in legal action. The potential penalties for non-compliance could include significant fines or other civil penalties, as well as potential criminal charges in cases where non-compliance leads to accidents or fatalities. The specific penalties are not detailed in the provided text, but they could be severe given the safety-critical nature of the directive.