COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 106 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Rolls Royce Turbine Engines - Spey Series
AD/RRT-S/6 Malfunction of Bleed Valve Mechanism Featuring Mod. 5866 - Operational and Maintenance Action
11/82
Applicability: Rolls Royce Spey 555-15, 15H, 15N and 15P engines featuring MOD. 5866 (SB SP72-916).
Requirement: Rolls Royce Spey Alert SB No. SP72-A963. Compliance: Forthwith.
Background: There have recently been reports of engines featuring Bleed Valve Mechanism MOD. 5866 showing an unacceptable rise in T.G.T. at low power conditions in the following cases:-
- Immediately on throttle advance from a low power setting where HP RPM stagnates, particularly following engine deceleration.
B. Less frequently - during steady state running at low power settings.
This AD is issued to alert flight and maintenance crews of the possibility of this condition occurring and precautions which should be taken.
Overview
The Civil Aviation Regulations 1998, as amended by the legislative instrument F2006B06687, address specific operational and maintenance concerns related to Rolls Royce Spey series turbine engines, particularly those featuring the bleed valve mechanism modification 5866. This regulation was introduced to address instances where engines with this particular modification exhibited an unacceptable rise in turbine gas temperature (TGT) under certain conditions. The problem it aims to resolve includes an increase in TGT at low power settings, particularly upon immediate throttle advancement from low power or during steady state operation at low power settings. This issue has been reported to lead to potential safety hazards that necessitate immediate attention and compliance by flight and maintenance crews. The objective of this directive, issued by the Civil Aviation Safety Authority, is to ensure the safety of aircraft operations by providing clear guidelines and alerts for the identification and mitigation of the malfunctions associated with the specified engine modifications.
Enacted by the Commonwealth of Australia, the regulation is part of the broader framework designed to maintain the highest safety standards in civil aviation. It mandates compliance with Rolls Royce Spey Alert Service Bulletin No. SP72-A963, ensuring that any affected engines are serviced and monitored appropriately. The policy objective is to prevent potential engine failures that could compromise flight safety, thereby protecting both the crew and passengers on board.
Scope and Application
The Civil Aviation Regulations 1998, specifically Part 39 - 106, under the Civil Aviation Safety Authority's Schedule of Airworthiness Directives, addresses the safety and operational standards for Rolls Royce Turbine Engines of the Spey series. The legislation applies to the specific variants of Rolls Royce Spey engines, namely the 555-15, 15H, 15N, and 15P models, which incorporate the Bleed Valve Mechanism Modification 5866 (SB SP72-916). The directive mandates compliance with Rolls Royce Service Bulletin No. SP72-A963, necessitating immediate action to mitigate risks associated with an unacceptable rise in Turbine Gas Temperature (T.G.T.) at low power conditions, particularly during throttle advances from low power settings where HP RPM stagnates or during steady state running at low power settings. The geographic and jurisdictional reach of this legislation is national, with the Civil Aviation Safety Authority overseeing compliance across Australia. There are no stated exclusions or exemptions within this directive; it is imperative that all applicable engines adhere to the specified requirements to ensure airworthiness and safety. The directive extends its application through subordinate instruments, which may include further detailed operational and maintenance procedures to be followed by flight and maintenance crews.
Key Provisions
The Civil Aviation Regulations 1998, specifically Part 39, Section 106, includes a schedule of airworthiness directives that govern the operational safety of aircraft engines. Section AD/RRT-S/6 pertains to Rolls Royce Turbine Engines of the Spey series, particularly those with Bleed Valve Mechanism Modification 5866 (SB SP72-916). This directive requires Rolls Royce Spey Alert Service Bulletin No. SP72-A963 to be complied with immediately (Section 11/82). The directive applies to Rolls Royce Spey 555-15, 15H, 15N, and 15P engines featuring Modification 5866, which have been identified to exhibit issues with bleed valve mechanisms.
The obligations imposed by this directive on the parties involved, such as aircraft operators and maintenance personnel, include a requirement for immediate compliance with the specified service bulletin. This involves implementing the recommended operational and maintenance actions to mitigate the risk of malfunction, particularly in scenarios where there is an unacceptable rise in turbine gas temperature (TGT) at low power conditions. Such conditions may occur immediately on throttle advance from a low power setting, particularly after engine deceleration, or less frequently during steady state running at low power settings.
Failure to adhere to the requirements set out in this airworthiness directive can result in serious consequences. Operational breaches may compromise the safety and airworthiness of the aircraft, potentially leading to engine failure or other critical malfunctions during flight. The regulatory framework provides for both civil and criminal penalties for non-compliance. Civil penalties can include fines and sanctions against the operators or maintenance providers, while criminal penalties may be imposed in cases of gross negligence or willful disregard of the regulations. The specific penalties can vary but are designed to ensure stringent compliance with aviation safety standards to protect public safety.