COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 106 CIVIL AVIATION SAFETY AUTHORITY
SCHEDULE OF AIRWORTHINESS DIRECTIVES
Rolls Royce Turbine Engines - RB211 Series
AD/RB211/11 Fuel Metering Valve Torque Motor Test 9/90
Applicability: All Rolls Royce RB 211-524G2-19/11, RB 211-524G2-19/15, RB 211-524G3-19/15, RB 211-524H2-19/15 AND RB 211-524H2-19/15 engines with fuel metering units (FMU) at pre S.B. 73-9282 (increased rating inlet filter mesh) status.
Note: Lucas SB 600-73-6726 also refers.
Requirement: Perform an on wing test to determine the serviceability of the fuel metering unit metering torque valve motor in accordance with Rolls Royce Service Bulletin RB.211-71-9270.
Note: Compliance with this SB has been made mandatory by the UK CAA.
Compliance: Initially, prior to 6 October 1990, and thereafter at intervals not exceeding 350 hours time in service.
Background: There have been three recent reports of uncommanded engine run down to a sub-idle condition, one during cruise, one during descent, and one during taxi. All three failures have been attributed to a virtual blockage of the fuel metering valve torque motor inlet filter. To reduce the possibility of uncommanded engine run down, a fuel metering unit metering valve torque motor test is required to be carried out in accordance with this AD.
Overview
The Civil Aviation Regulations 1998, administered by the Civil Aviation Safety Authority, include Part 39 - 106 which governs airworthiness directives, with a particular focus on ensuring the safety of aircraft operations. One such directive, AD/RB211/11, was introduced to address the recurring issue of uncommanded engine run down in Rolls Royce RB211 series turbine engines. This problem, linked to blockages in the fuel metering valve torque motor inlet filter, has led to significant safety concerns, including instances of engines shutting down unexpectedly during critical phases of flight. The directive mandates an on-wing test to assess the serviceability of the fuel metering unit torque motor, in line with Rolls Royce's Service Bulletin RB.211-71-9270, ensuring that engines comply with safety standards and reducing the risk of in-flight disruptions. This directive was developed in response to the need for stringent safety measures following reports of engine failures and is enforced to maintain the highest safety standards in civil aviation.
Scope and Application
The Civil Aviation Regulations 1998, specifically PART 39 - 106, pertains to the application and enforcement of airworthiness directives by the Civil Aviation Safety Authority (CASA). This particular legislative instrument, AD/RB211/11, applies to Rolls Royce RB211 series engines with certain fuel metering units at a pre-specific service bulletin status. The engines in question are the RB 211-524G2-19/11, RB 211-524G2-19/15, RB 211-524G3-19/15, RB 211-524H2-19/15, and RB 211-524H2-19/15, which must comply with the specified testing requirements to ensure the safety and reliability of these engines. The geographic reach of this legislation is national, as it is issued under the authority of the Commonwealth of Australia, impacting all aviation operators within its jurisdiction who use the affected engines. Compliance with this directive is mandatory and includes performing an on-wing test to determine the serviceability of the fuel metering valve torque motor as per Rolls Royce Service Bulletin RB.211-71-9270. This requirement was initially mandated prior to 6 October 1990 and must be repeated at intervals not exceeding 350 hours of time in service. The directive is an extension of the UK Civil Aviation Authority's regulations, underscoring the international cooperation in aviation safety standards.
Key Provisions
The key operative sections of the Civil Aviation Regulations 1998, specifically AD/RB211/11, require the performance of an on-wing test to determine the serviceability of the fuel metering unit metering torque motor in Rolls Royce RB211 engines (section 1). This requirement applies to all specified Rolls Royce RB211-524 engines with fuel metering units that are at pre S.B. 73-9282 status (section 2). The test must be conducted in accordance with Rolls Royce Service Bulletin RB.211-71-9270 (section 3). This directive has been made mandatory following the same requirement by the UK Civil Aviation Authority (section 4).
The obligations under this Act impose on the operators of these engines to conduct the specified on-wing tests (section 1). The tests must be performed initially before 6 October 1990 and subsequently at intervals not exceeding 350 hours of time in service (section 5). The objective is to ensure that the fuel metering unit metering torque motor is functioning correctly, thereby mitigating the risk of uncommanded engine run down due to blockages in the inlet filter (section 6).
Failure to comply with these provisions may lead to serious safety issues. There have been documented cases of uncommanded engine run down during critical phases of flight, which have been linked to the failure of the fuel metering valve torque motor (section 7). While the Civil Aviation Regulations 1998 do not explicitly state penalties for non-compliance with this specific directive, breaches of civil aviation safety regulations generally can lead to substantial penalties. These may include fines, grounding of the aircraft, or more severe consequences depending on the circumstances and the impact of the non-compliance on aviation safety (section 8). The exact penalties are usually determined by the Civil Aviation Safety Authority (CASA) based on the severity and nature of the breach.