AD/VIPER/8 - Oil Tank and Oil Pump Drain Valves

Overview

The Civil Aviation Regulations 1998, specifically within Part 39 concerning airworthiness directives, introduced the requirement for Rolls Royce Viper Series engine inspections to address issues related to oil tank and oil pump drain valve assemblies. Enacted by the Commonwealth of Australia, this regulation was aimed at ensuring the safety and reliability of Viper Mk 520, 521 and 522 engines, which are used in various aircraft. The problem identified was the risk of total loss of oil pressure due to undetected oil leakage from the oil tank drain valve, potentially leading to catastrophic engine failure. The policy objective, as stated in the directive, is to mandate inspections in accordance with Rolls Royce's service bulletin, thereby mitigating the risk of such failures and maintaining high safety standards within the aviation industry. The Australian Civil Aviation Safety Authority, under the authority of the Civil Aviation Regulations 1998, issued this airworthiness directive to ensure that all relevant Viper Mk engines are inspected before being placed into service or installed in aircraft. This directive references a similar UK directive, CAA UK Airworthiness Directive 030-04-90, to align with international safety standards and practices. The directive ensures that any engines in service prior to 6 August 1990 and those not yet installed in aircraft must undergo the necessary inspections to prevent oil leakage and subsequent loss of oil pressure.

Scope and Application

The Civil Aviation Regulations 1998, specifically Part 39 - 106, applies to the Rolls Royce Viper Series engines, including the Viper Mk 520, 521, and 522 engines currently in service or being prepared for installation in aircraft. This regulation mandates that these engines undergo an inspection of their oil tank and oil pump drain valve assemblies. The inspection must comply with the requirements outlined in Rolls Royce Viper Mks 520, 521, and 522 Service Bulletin No 72-A381, which was informed by the findings detailed in the CAA UK Airworthiness Directive 030-04-90. The requirement applies to engines in service before 6 August 1990 and to uninstalled engines prior to their installation in an aircraft. Failure to adhere to these directives could result in the critical issue of a total loss of oil pressure, which has been demonstrated to lead to significant engine damage. The regulation ensures that any identified defects, such as an improperly positioned oil tank drain valve cap or a stuck open drain valve, are rectified to maintain the airworthiness and safety of the aircraft.

Key Provisions

The key provisions of the Civil Aviation Regulations 1998, Part 39 - 106, specifically concerning Rolls Royce Viper Series Turbine Engines (AD/VIPER/8), mandate inspections of the oil tank and oil pump drain valve assemblies. This directive applies to Viper Mk 520, 521, and 522 engines, as outlined in section 1. These inspections must be conducted in accordance with Rolls Royce Viper Mks 520, 521, and 522 Service Bulletin No 72-A381, with reference to CAA UK Airworthiness Directive 030-04-90. Compliance with these regulations is crucial for engines already in service prior to 6 August 1990, and for any uninstalled engines before their installation in an aircraft, as stated in section 2. Section 3 of the regulation details the obligations imposed on the parties or entities governed by the Act. Specifically, operators of Viper Mk 520, 521, and 522 engines must ensure that the required inspections of oil tank and oil pump drain valve assemblies are performed meticulously. This includes verifying that the oil tank drain valve cap is properly positioned and that the drain valve is not stuck open, to prevent a total loss of oil pressure. The directive requires adherence to the procedures specified in Rolls Royce's service bulletin and the corresponding UK CAA directive, ensuring that all necessary measures are taken to maintain the safety and airworthiness of the engines. Section 4 outlines the potential consequences of non-compliance with the regulation. Failure to inspect the oil tank and oil pump drain valve assemblies as required could result in severe operational issues, such as total loss of oil pressure, which was evidenced in a test flight where an improperly positioned valve cap and a stuck open drain valve led to a rapid loss of oil. This could compromise the safety of the aircraft and its passengers, leading to civil or criminal penalties under the Civil Aviation Regulations. The specific maximum penalties are not detailed in the text, but non-compliance could result in significant enforcement actions by the Civil Aviation Safety Authority (CASA).