AIRWORTHINESS DIRECTIVE
For the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/AL250/80 and issues the following AD under subregulation 39.1 (1) of CAR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.
Allison Turbine Engines - 250 Series
AD/AL 250/80
Amdt 1
Gearbox - Torquemeter Gearshaft Assembly 8/2002
Applicability: All 250-C20, -C20R, - B17 and B17F Series II engines with less than 100 hours’ time in service since the installation of one of the following part number (P/N) helical torquemeter gearshaft assemblies.
23035299, 23038191, 6889701, 6871218, 6870941, 23030857, 23004504, 23037441.
Note 1: This Directive is only applicable to engines which have had maintenance carried out on the gearbox in the last 100 hours engine time in service and had one of the above part number gearshafts installed with less than 100 hours’ time since new during that maintenance.
Requirement: Remove applicable helical torquemeter gearshaft assemblies from service in accordance with one of the following Rolls Royce Alert Commercial Engine Bulletins as applicable by engine model; CEB A-1386R1, CEB A-72-4087R1, TP CEB A- 1331R1, TP CEB A-72-2083R1.
Compliance with the previous issue of these Bulletins satisfies the requirements of this Directive.
Note 2: FAA AD 2001-24-12 refers.
Compliance: Unless previously accomplished, effective 8 August 2002; before further flight.
This amendment becomes effective on 8 August 2002.
Background: This Directive has been amended to reflect FAA AD 2001-24-12. Rolls Royce Alert Commercial Engine Bulletins CEB A-1386R1, CEB A-72-4087R1, TP CEB A- 1331R1, TP CEB A-72-2083R1 have been revised to reflect additional data. The original Directive was issued to address a reported power turbine overspeed that resulted in an uncontained release of turbine blades and turbine disc fragments. The overspeed release resulted in an engine fire and damage to the aircraft. The overspeed resulted from a high cycle fatigue initiated failure of the helical Torquemeter gearshaft. The examination of the failed gearshaft revealed evidence of a pre-existing crack.
Allison Turbine Engines - 250 Series
AD/AL250/80 Amdt 1 (continued)
The original issue of this Airworthiness Directive became effective on 17 October 2001.
Eugene Paul Holzapfel
Delegate of the Civil Aviation Safety Authority 28 June 2002
The above AD is notified in the Commonwealth of Australia Gazette on 17 July 2002.
Overview
The Civil Aviation Safety Authority (CASA) introduced the Airworthiness Directive (AD) AD/AL 250/80 Amdt 1 in 2002 to address safety concerns related to Allison Turbine Engines - 250 Series, specifically the helical torquemeter gearshaft assemblies in certain engine models. This legislative instrument was enacted to mandate corrective actions to prevent power turbine overspeeds, which had previously caused uncontained releases of turbine blades and fragments, leading to engine fires and aircraft damage. The AD applies to 250-C20, -C20R, -B17 and B17F Series II engines with specified part number gearshaft assemblies installed within the last 100 hours of engine time in service. Compliance with Rolls Royce Alert Commercial Engine Bulletins is required to remove these assemblies from service. The directive aims to ensure continued airworthiness and safety in aviation operations by addressing identified risks associated with the affected engine components.
Scope and Application
The Airworthiness Directive issued under the Civil Aviation Regulations 1998 governs the safety requirements for specific Allison Turbine Engines - 250 Series, specifically the 250-C20, -C20R, -B17, and B17F Series II engines that have had maintenance work on the gearbox in the last 100 hours of engine time in service, and where the helical torquemeter gearshaft assemblies of certain part numbers were installed less than 100 hours since new during that maintenance. The directive applies to these engines in circumstances where the helical torquemeter gearshaft assemblies must be removed from service to correct an unsafe condition. Compliance with the directive is mandatory and must be achieved before further flight, with the compliance date set as 8 August 2002. The directive’s geographic reach is nationwide, as it is issued by the Civil Aviation Safety Authority, a federal agency of the Australian government. There are no stated exclusions or exemptions in the directive, and its application is not extended or restricted through subordinate instruments.
Key Provisions
This Airworthiness Directive (AD) issued by the Civil Aviation Safety Authority (CASA) pertains to Allison Turbine Engines - 250 Series, specifically those with certain part numbers of helical torquemeter gearshaft assemblies that have less than 100 hours of time in service since installation (section 2). The AD requires the removal of the specified helical torquemeter gearshaft assemblies from service, in accordance with applicable Rolls Royce Alert Commercial Engine Bulletins (section 3). Compliance with the previous issues of these bulletins satisfies the requirements of this directive. Compliance with this AD must be achieved before further flight and is effective from 8 August 2002 (section 4).
The AD imposes obligations on the entities governed by it to ensure that the specified Allison Turbine Engines - 250 Series comply with the requirements set out in the AD. This includes the removal of the specified helical torquemeter gearshaft assemblies from service in accordance with the applicable Rolls Royce Alert Commercial Engine Bulletins. The AD also requires that compliance is achieved before further flight and that the compliance is effective from the specified date (section 4).
Failure to comply with this AD may result in civil or criminal consequences, including potential penalties. The specific penalties for non-compliance with this AD are not explicitly stated in the text, but non-compliance with CASA regulations can result in significant fines and legal action. It is important for entities governed by this AD to ensure compliance to avoid any potential legal or financial repercussions (section 5).