COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 106 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Allison Turbine Engines - 250 Series
AD/AL 250/70 No. 8 Bearing Scavenge Line Air/Oil Separator 8/86
Applicability: 250-C28B and C28C series engines with engine and turbine serial numbers listed in the Requirement Document.
Requirement: Modify the engine oil system in accordance with Allison Alert CEB-A-72-2138 dated 15 May 1986.
Compliance: Within 100 hours of engine operation after 31 August 1986 but no later than 31 January 1987.
Background: This Directive is issued to install an air/oil separator in the No. 8 bearing scavenge line to improve venting of the No. 8 bearing oil sump. Excess pressure in the No. 8 bearing sump may result in internal oil fire and cause a No. 1 turbine wheel failure.
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 within Australia. Among these regulations is PART 39 - 106, which includes Airworthiness Directives (ADs) designed to ensure the safety of aircraft operations. One such directive, AD/AL 250/70, pertains to Allison Turbine Engines of the 250 Series and specifically addresses issues with the No. 8 Bearing Scavenge Line Air/Oil Separator. This directive was introduced to address the problem of excess pressure in the No. 8 bearing oil sump, which could lead to an internal oil fire and subsequent No. 1 turbine wheel failure. The objective of this AD is to mandate the modification of the engine oil system in accordance with specific technical guidelines to prevent such safety hazards and ensure compliance within a stipulated timeframe.
Scope and Application
The Civil Aviation Regulations 1998, under Part 39 - 106, establish the scope and application of the Airworthiness Directives (AD) which govern the maintenance and safety of aircraft within Australia. Specifically, AD/AL 250/70 pertains to Allison Turbine Engines of the 250 Series, particularly the 250-C28B and C28C series engines, identified by their specific engine and turbine serial numbers. This directive applies to all operators of aircraft utilising these engines and mandates compliance with the installation of an air/oil separator in the No. 8 bearing scavenge line to enhance the venting process of the No. 8 bearing oil sump, mitigating the risk of internal oil fires and subsequent turbine wheel failure. The directive is geographically applicable across Australia, as it is a Commonwealth regulation. The requirement to modify the engine oil system must be fulfilled within 100 hours of engine operation following 31 August 1986, with a strict deadline of 31 January 1987. No exclusions or exemptions are specified within this directive, thereby making compliance mandatory for all relevant engine operators within the stated timeframe. The scope of this directive is further extended through subordinate instruments, which provide detailed procedural and technical specifications to ensure uniform implementation across the industry.
Key Provisions
The Civil Aviation Regulations 1998, specifically Part 39 - 106, includes Airworthiness Directives (AD) that mandate specific maintenance actions to ensure the continued safety of aircraft. One such directive, AD/AL 250/70 (paragraph 1), applies to Allison Turbine Engines of the 250 Series, particularly the 250-C28B and C28C models with specific serial numbers as outlined in the Requirement Document. The directive requires a modification to the engine oil system in line with Allison Alert CEB-A-72-2138 dated 15 May 1986. This modification is essential to install an air/oil separator in the No. 8 bearing scavenge line to effectively manage the venting of the No. 8 bearing oil sump. The primary goal of this modification is to prevent excess pressure in the No. 8 bearing sump, which could otherwise lead to an internal oil fire and subsequent failure of the No. 1 turbine wheel.
The obligations imposed by AD/AL 250/70 are clear and must be adhered to by the relevant parties. Operators of aircraft equipped with the specified Allison Turbine Engines must ensure that the required modifications are completed within a stipulated timeframe. According to the directive, compliance is necessary within 100 hours of engine operation following 31 August 1986, but no later than 31 January 1987. This timeline ensures that the modifications are implemented promptly to mitigate any potential safety risks associated with the engine design. Failure to comply with these obligations can have serious repercussions for the safety of the aircraft and its occupants.
Breaches of the obligations set forth in AD/AL 250/70 can result in severe consequences, including both civil and criminal penalties. While the specific penalties are not detailed in the text, it is reasonable to infer that non-compliance with such critical safety directives can lead to significant regulatory action. The Civil Aviation Safety Authority (CASA) has the authority to enforce these regulations and can impose fines, suspend or revoke airworthiness certificates, and take other enforcement actions against operators who fail to adhere to the directive. The gravity of the potential consequences underscores the importance of strict compliance with the specified requirements.