AD/ENG/5 Amdt 9 - Turbine Engine Continuing Airworthiness Requirements

Administered by Department of Infrastructure, Transport, Regional Development, Communications, Sport and the Arts

Legislation au F2006B09561 Not in force Legislative Instrument

Legislation content

 

 


AIRWORTHINESS DIRECTIVE

On the effective date specified below, and for the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/ENG/5 Amdt 8 and issues the following AD under subregulation 39.1 (1) of CASR 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.

 

Engines - General

 

AD/ENG/5

Amdt 9


Turbine Engine Continuing Airworthiness Requirements


10/2004

 

Applicability: All turbine engines; other than engines installed in:

 

  1. Aircraft administered by an approved sports aviation body; and

 

2.         Aircraft issued with a limited category certificate of airworthiness under regulation 21.189 of the CASR; and

 

3.         Aircraft issued with an experimental certificate under regulation 21.195A of the CASR.

 

Requirement: 1. OVERHAUL/INSPECTION PERIODS FOR TURBINE ENGINES

 

1.1    Turbine engines shall be overhauled or inspected at periods not exceeding:

 

(a)     As specifically detailed in Requirements 1.2, 1.3 and 1.4 of this Directive; or

 

(b)     At the recommended hours in service published by the engine manufacturer; or

 

(c)     As detailed in an approved system of maintenance.

 

1.2    Honeywell TPE331 series engines:

 

(a)     Honeywell TPE331 series engines shall be overhauled at periods as listed in, and subject to the requirements of, the appropriate Honeywell Service Bulletins detailing TPE331 series engine time between overhaul (TBO) intervals and requirements. For the purpose of this Directive, annual utilisation, or type of operation, are not requisites to establish a TBO period for Honeywell TPE331-1, -2, -3, -5, -6, -8, -10, -11, -12 series engines; or

 

(b)     Inspected in accordance with, and subject to the requirements of, a Honeywell published Continuous Airworthiness Maintenance Operation (CAM) program applicable to the engine model. For the purpose of this Directive, annual utilisation, or type of operation, are not requisites to establish a TBO period for Honeywell TPE331-1, -2, -3, -5, -6, -8, -10, -11,

-12 series engines; or

 

(c)     As detailed in an approved system of maintenance.

 

1.3    Pratt and Whitney Canada PT6A series engines other than PT6A engines installed in aircraft conducting aerial agricultural operations or fire fighting operations:

 

(a)     PT6A series engines shall be overhauled at periods as listed in, and subject to the requirements of, the appropriate Pratt and Whitney Canada Service Bulletin detailing Pratt and Whitney Canada PT6A operating time between overhaul and hot section inspection frequency; or

 

(b)     At periods not to exceed 5,000 hours time in service, subject to compliance with the maintenance requirements detailed in Appendix A of this Directive; or

 

(c)     As detailed in an approved system of maintenance.

 

1.4    Pratt and Whitney Canada PT6A series engines installed in aircraft conducting aerial agricultural operations or fire fighting operations:

 

(a)     PT6A series engines shall be overhauled at periods as listed in, and subject to the requirements of, the appropriate Pratt and Whitney Canada Service Bulletin detailing Pratt and Whitney Canada PT6A operating time between overhaul and hot section inspection frequency; or

 

(b)     In accordance with an engine on-condition program having regard to that detailed in Appendix B of this Directive; or

 

(c)      As detailed in an approved system of maintenance. Compliance: Not later than 1 January 2005.

This Amendment becomes effective on 30 September 2004.

 

Background: This Directive is issued to require turbine engines to be overhauled or inspected at specified intervals. The Directive addresses the engine certification requirement to publish instructions for the continued airworthiness of a type-certificated engine. In addition to listing the manufacturer’s published TBO or inspection periods, the Directive also provides unique CASA initiated options for certain turbine engines.

 

This amendment deletes the previous requirement for repair and overhaul of turbine engines because these requirements are already reflected in the regulations. This amendment also provides an option to use PWC’s WebECTM option to conduct engine condition trend monitoring.


Gary J Carr

Delegate of the Civil Aviation Safety Authority 19 August 2004

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 


The above AD is notified in the Commonwealth of Australia Gazette on 8 September 2004.

 

AD/ENG/5

Amdt 9


PT6A Enhanced Maintenance Program Appendix A

 

 

 

REQUIREMENTS

 

The PT6A engine maintenance program shall be carried out in accordance with approved maintenance data and detailed in a system of maintenance approved under Civil Aviation Regulation (CAR 1988) 42M. The system of maintenance shall include, but need not be limited to, the following requirements.

 

  1. PT6A engines not previously maintained in accordance with a maintenance program reflecting the intent of the maintenance requirements detailed in this Appendix and with engine hours in service greater than 75% of the Pratt and Whitney Canada published Time Between Overhaul (TBO) period at the time of introduction, shall be subject to a pro-rata TBO period based on the Pratt and Whitney Canada published TBO period; and

 

2.         The engine shall be on an Engine Condition Trend Monitoring (ECTM) program, including data collection, analysis and follow up actions. This program shall be in accordance with the Pratt and Whitney Canada ECTM Users Guide and Reference Manual (PWC P/N 3031900) or WebECTM per PWC SIL PT6A-122 and include requirements for qualification and training for personnel conducting ECTM; and

 

3.         Hot section inspections shall be carried out at intervals not to exceed:

 

(a)     1250 hours time in service; or

 

(b)     1760 hours time in service subject to a boroscope inspection of the engine hot section for evidence of cracks, distortion, burning and coating loss at intervals not to exceed 610 hours time in service; and

 

4.         All fuel nozzles shall be cleaned and flow checked at intervals not to exceed 460 hours time in service; and

 

5.         The engine oil filter element shall be inspected for contamination at intervals not to exceed 220 hours time in service; and

 

6.         The reduction gearbox chip detector shall be inspected for contamination, or continuity, at intervals not to exceed 220 hours time in service; and

 

7.         Engines with an annual utilisation of less than 500 hours per annum, an engine oil change shall be carried out at intervals not to exceed 12 calendar months time in service; and

 

8.         An inspection of the 1st stage compressor for evidence of Foreign Object damage (FOD), corrosion and contamination shall be carried out at intervals not to exceed 220 hours time in service; and

 

9.         A compressor power recovery wash shall be carried out in response to trend monitoring parameter deviations, or at intervals not to exceed 220 hours time in service, or 3 calendar months, whichever occurs first; and

 

10.    All life limited components shall be replaced at engine manufacturer’s published life limits per AD/ENG/7; and

 

11.    Critical components shall be inspected at intervals specified by the engine manufacturer; and

 

12.    TBO of accessories shall be per the recommendations of Pratt and Whitney Canada.

 

13.    The maintenance program shall be reviewed and revised as required at periods not to exceed 2 years taking into consideration all major defects and defects that affect engine durability. Outcome of the review shall be reported to CASA after each review under Major Defect Report (MDR) / Service Difficulty Report (SDR) system referring to AD/ENG/5.

 

AD/ENG/5

Amdt 9


PT6A Agricultural Operations On-Condition Maintenance Program


Appendix B

 

 

 

REQUIREMENTS

 

The PT6A engine on-condition maintenance program shall be carried out in accordance with approved maintenance data and detailed in a system of maintenance approved under Civil Aviation Regulation (1988) 42M. The system of maintenance shall include, but need not be limited to, the following requirements:

 

  1. The engine shall be on an Engine Condition Trend Monitoring (ECTM) program, including, data collection, analysis and follow up actions, qualification and training of personnel. This program shall be in accordance with the Pratt and Whitney Canada ECTM Users Guide and Reference Manual (PWC P/N 3031900) or WebECTM per PWC SIL PT6A-122 and include requirements for qualification and training for personnel conducting ECTM; and

 

2.         Hot section inspections shall be carried out at intervals not to exceed 1510 hours time in service; and

 

3.         All fuel nozzles shall be cleaned and flow checked at intervals not to exceed 460 hours time in service; and

 

4.         The engine oil filter element shall be inspected for contamination at intervals not to exceed 220 hours time in service; and

 

5.         The reduction gearbox chip detector shall be inspected for contamination, or continuity, at intervals not to exceed 220 hours time in service; and

 

6.         Engines with an annual utilisation of less than 500 hours per annum, an engine oil change shall be carried out at intervals not to exceed 12 calendar months time in service; and

 

7.         Engines not incorporating an engine air intake positive barrier air filter, an inspection of the 1st stage compressor for evidence of Foreign Object Damage (FOD), corrosion and contamination shall be carried out at intervals not to exceed 220 hours time in service; and

 

8.         All life limited components shall be replaced at the engine manufacturer’s published life limits per AD/ENG/7; and

 

9.         Critical components shall be inspected at intervals specified by Pratt and Whitney Canada; and

 

10.    Engine work-scope during engine shop visits shall have regard to the recommendations of Pratt and Whitney Canada, including minimum modification standards for engine durability; and

 

11.    TBO of accessories shall have regard to the recommendations of Pratt and Whitney Canada.

 

12.    The on-condition program shall be reviewed and revised as required at periods not to exceed 2 years taking into consideration all major defects and defects that affect engine durability. Outcome of the review shall be reported to CASA after each review under Major Defect Report (MDR) / Service difficulty Report (SDR) system referring to AD/ENG/5.

Overview

The Civil Aviation Safety Authority (CASA) issued the Airworthiness Directive (AD) AD/ENG/5 Amdt 9 in 2004 to address the need for specified overhaul and inspection periods for turbine engines, ensuring their continued airworthiness. This legislative instrument was enacted to comply with the Civil Aviation Safety Regulations 1998 (CASR 1998), ensuring that turbine engines are maintained according to set standards to prevent unsafe conditions. The directive specifically targets turbine engines excluding those in certain aircraft categories, aiming to enhance safety by mandating regular inspections and overhauls based on manufacturer recommendations or approved maintenance systems. CASA's policy objective is to maintain the highest safety standards in aviation by providing clear, enforceable guidelines for engine maintenance.

Scope and Application

The Airworthiness Directive (AD) AD/ENG/5 Amdt 9 applies to all turbine engines except those installed in aircraft administered by an approved sports aviation body, those issued with a limited category certificate of airworthiness under regulation 21.189 of the Civil Aviation Safety Regulations (CASR), and those issued with an experimental certificate under regulation 21.195A of the CASR. The AD mandates specific overhaul and inspection periods for turbine engines to ensure their continuing airworthiness. Turbine engines must be overhauled or inspected at intervals not exceeding the periods specified in the AD, the recommended hours in service published by the engine manufacturer, or as detailed in an approved system of maintenance. The AD also provides unique CASA-initiated options for certain turbine engines, such as the Honeywell TPE331 series and Pratt and Whitney Canada PT6A series engines. The AD applies nationally across the Commonwealth of Australia and is enforced by the Civil Aviation Safety Authority (CASA). Compliance with this AD is mandatory, and failure to adhere to the specified overhaul and inspection periods may result in the grounding of affected aircraft. The AD may be extended or restricted through subordinate instruments, such as notices to airmen (NOTAMs) or additional guidance material issued by CASA.

Key Provisions

The primary operative sections of the Airworthiness Directive (AD) AD/ENG/5 Amdt 9 detail the requirements for turbine engines to ensure continued airworthiness. Section 1 of the AD mandates that turbine engines must be overhauled or inspected at specific intervals. These intervals can be as detailed in the requirements of the AD itself (Section 1.2 for Honeywell TPE331 series engines, Section 1.3 for Pratt and Whitney Canada PT6A series engines used in general operations, and Section 1.4 for PT6A series engines used in aerial agricultural or fire-fighting operations) or at periods recommended by the engine manufacturer or as detailed in an approved system of maintenance (Section 1.1). Compliance with these requirements must be achieved by 1 January 2005. The AD imposes several obligations on the parties and entities it governs. Firstly, it mandates that turbine engines must adhere to prescribed overhaul and inspection intervals. Specifically, Honeywell TPE331 series engines must be overhauled or inspected in accordance with Honeywell Service Bulletins or an approved system of maintenance. Pratt and Whitney Canada PT6A series engines must be overhauled or inspected either according to the manufacturer's bulletins, at intervals not exceeding 5,000 hours time in service, or as per an approved maintenance system. For engines used in aerial agricultural or fire-fighting operations, an on-condition maintenance program must be implemented. The AD further outlines detailed maintenance requirements for PT6A engines under two scenarios. For engines not previously maintained in accordance with a program reflecting the maintenance requirements and with engine hours in service greater than 75% of the TBO period, a pro-rata TBO period must be applied. Additionally, these engines must be subject to an Engine Condition Trend Monitoring (ECTM) program, hot section inspections, fuel nozzle cleaning, engine oil filter inspections, reduction gearbox chip detector inspections, and other specific maintenance tasks. Critical components must be inspected at intervals specified by Pratt and Whitney Canada, and life-limited components must be replaced at the engine manufacturer's published life limits. Breaching the requirements set out in the AD may result in significant consequences. Although the AD itself does not specify penalties for non-compliance, failure to adhere to airworthiness directives can lead to serious ramifications under the Civil Aviation Safety Authority (CASA) regulations. Such non-compliance could result in enforcement actions, including fines, suspension or revocation of airworthiness certificates, and legal proceedings. The severity of these penalties may vary based on the extent and impact of the non-compliance.

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