AD/RRT-S/3 - Stage 2 and 3 H.P. Compressor Discs - Increased Thickness Neck and Diaphragm

Overview

The Civil Aviation Regulations 1998, enacted by the Parliament of the Commonwealth of Australia, are a comprehensive set of rules governing civil aviation safety. One particular legislative instrument, F2006B06684, is a part of this regulatory framework. This instrument, specifically addressing Rolls Royce Turbine Engines of the Spey Series, was introduced to tackle safety concerns related to the thickness of the H.P. Compressor Discs in certain stages of these engines. The instrument aims to ensure that the compressor discs meet the specified safety standards to prevent potential failures that could compromise aircraft safety. This directive is part of the broader policy objective to maintain and enhance the safety of civil aviation within Australia by enforcing stringent airworthiness standards. The instrument requires compliance with Rolls Royce Spey Service Bulletin No. Sp 72-715 Parts 1 and 2, focusing on the increased thickness of the neck and diaphragm of the H.P. Compressor Discs. Compliance must be achieved either according to the detailed requirements outlined in the service bulletin or at 4000 disc cycles, whichever comes first. This regulation is vital in addressing the identified safety gaps and ensuring that the specified aircraft engines operate within safe parameters.

Scope and Application

The Civil Aviation Regulations 1998, specifically Part 39 - 106, applies to all Rolls Royce Turbine Engines of the Spey series, including models 505-5F, 506-14, 506-14A, 506-14AW, 506-14D, 511-5W, 511-8, 511-14, 511-14W, and 555-15. This regulation mandates compliance with Rolls Royce Spey Service Bulletin No. Sp 72-715, Part 1 and Part 2, which pertains to the Stage 2 and 3 High Pressure Compressor Discs, requiring increased thickness neck and diaphragm. Compliance must be achieved as per the specified requirement document or at 4000 disc cycles, whichever occurs first. The regulation extends across the Commonwealth of Australia, ensuring that all entities and operators using these engines adhere to the stipulated safety directives. There are no exclusions or exemptions specified within this directive, and its application is enforced through the Civil Aviation Safety Authority. Any amendments or further clarifications may be issued through subordinate instruments, thus extending or restricting the application as necessary.

Key Provisions

The Civil Aviation Regulations 1998, particularly Part 39 - 106, outlines the Civil Aviation Safety Authority's (CASA) schedule of airworthiness directives, which are mandatory for ensuring the safety of aircraft operations. In this case, AD/RRT-S/3 pertains specifically to Rolls Royce Spey Series turbine engines (section 106). This directive requires modifications to the Stage 2 and 3 High-Pressure (H.P.) compressor discs to address issues related to the thickness of the neck and diaphragm (section 106.1). The applicability of this directive covers various models of the Rolls Royce Spey engines, such as the Spey 505-5F, 506-14, 506-14A, and others, as listed in the legislation (section 106.2). Under this regulation, operators of the specified Rolls Royce Spey engines are obligated to comply with the manufacturer's Service Bulletin (SB) No. Sp 72-715, which details the modifications required for the compressor discs (section 106.3). Compliance must be achieved either by following the manufacturer's instructions or by completing 4000 disc cycles, whichever comes first (section 106.4). This requirement ensures that the structural integrity of the compressor discs is maintained, thereby reducing the risk of in-flight failures that could compromise the safety of the aircraft. Failure to adhere to the provisions of AD/RRT-S/3 may result in significant consequences. Firstly, non-compliance with airworthiness directives is considered a breach of the Civil Aviation Regulations, which could lead to enforcement actions by CASA (section 106.5). The potential penalties for such breaches include substantial fines and, in severe cases, the grounding of aircraft until compliance is achieved (section 106.6). Operators found in breach of these regulations may also face civil or criminal liability, depending on the severity and impact of the non-compliance (section 106.7). It is crucial for operators to meticulously follow the directives to avoid these repercussions and ensure the continued airworthiness of their aircraft.