Civil Aviation Safety Authority - AWB 72-1 - Engine Condition Trend Monitoring (
Civil Aviation Safety Authority - AWB 72-1 - Engine Condition Trend Monitoring (
Civil Aviation Safety Authority - AWB 72-1 - Engine Condition Trend Monitoring (
Search Search Search CASA... Home Operations Individuals Aircraft owners Aircraft operators Flight training Aerodromes Office of airspace regulation Sport aviation Class D Non-towered aerodromes Ground operations Dangerous goods Non-compliance notice Unmanned Aircraft Systems (UAS) General Aviation (GA) task force Regional Aviation Safety Forum (RASF) Drug and Alcohol Management Plans Airworthiness Maintenance regulations Personnel Certification and design Manufacturing Continuing airworthiness Airworthiness directives Maintenance organisations Flight test and evaluation Regulations and Policy Current rules Changing the rules Enforcement action Policy notices Australia's state safety program Safety information policy statement Performance based navigation (PBN) Licensing regulations Manuals and forms Manuals Forms CASA online store Temporary Management Instructions (TMIs) Education AviationWorx eLearning catalogue Flight Safety Australia
http://www.casa.gov.au/scripts/nc.dll?WCMS:STANDARD::pc=PC_93093[7/11/2013 5:31:02 PM]
Civil Aviation Safety Authority - AWB 72-1 - Engine Condition Trend Monitoring (ECTM)
Pilot guides and information OnTrack Human factors Safety management systems Seminars and workshops Aviation safety advisers Advice for air travellers CASA online store Out-n-Back Services Licences & registrations Service standards & fees Self Service Portal Permission application centre (PAC) Aviation medicals Delegates and authorised persons About CASA Contact CASA CASA board CASA's Director Recent media releases Corporate publications CASA on Twitter Corporate policy Careers at CASA Research and statistics Airworthiness Maintenance regulations Personnel Certification and design Manufacturing Continuing airworthiness Airworthiness bulletins Airworthiness advisory circulars International agreements Service difficulty reports Ageing Aircraft Management Plan (AAMP) Airworthiness directives Maintenance organisations Flight test and evaluation Home Airworthiness Continuing airworthiness Airworthiness bulletins AWB Engines AWB 72 - Engine (turbine/turboprop) AWB 72-1 - Engine Condition Trend Monitoring (ECTM)
Civil Aviation Safety Authority - AWB 72-1 - Engine Condition Trend Monitoring (ECTM)
Purpose
Engine Condition Trend Monitoring ( ECTM) is a process in which changes in certain performance parameters of engines are analyzed to identify engine performance deterioration and malfunction of engine components and accessories. The technical requirements of ECTM are specified by the engine manufacturer. This Airworthiness Bulletin (AWB) provides the elements to be considered while incorporating ECTM as part of an engine maintenance program to ensure reliable and consistent outcomes.
Background
In the initial findings of an investigation into an accident involving a Beechcraft King Air C90 aircraft, the ATSB has identified inadequate ECTM as a contributing factor. Early detection of engine deterioration is of critical importance to schedule timely maintenance action, and ECTM has been widely used to facilitate this. ECTM is considered to be part of a good engine maintenance program and is mandatory in the following instances. Turbine engine powered aircraft where the flight manual permits reduced power take offs, the flight manual will contain a mandatory requirement to have procedures to ensure that the engine will make the rated power. Incorporation of ECTM into the engine maintenance program, along with the specification of some engine parameter limits to ensure rated power, is one of the methods to meet this requirement. In circumstances where the ECTM is not carried out in real-time, it may be necessary to supplement ECTM with full rated engine runs at regular intervals to meet the flight manual requirements. Engines operating under an on-condition program where ECTM is specified as a requirement. Engines fitted to Approved Single Engine Turbine Powered Aircraft (ASETPA). Engines on extended Time Between Overhauls (TBO) as approved by AD/ENG/5 where ECTM is mandatory. Engines on extended TBO approved by the manufacturer where ECTM is specified as mandatory.
ECTM System
Effective implementation and integration of ECTM into the engine maintenance program requires the following sub-systems: Data acquisition Data entry Data analysis Follow-up actions Computer hardware and software High capacity transport aircraft manufactured by Boeing and Airbus usually have highly integrated real time data acquisition and analysis systems to support ECTM. This AWB is primarily focused on ECTM systems on Pratt and Whitney Canada engines even though the elements of the follow up action requirements detailed in this AWB and emanating from ECTM analysis are applicable to all types of ECTM systems.
Data Acquisition
ECTM relies on consistent and reliable engine performance data that includes altitude, outside air temperature (OAT), aircraft speed, turbine gas temperature, engine rpm, propeller rpm, power developed, fuel flow and others. Hence it is imperative that the required data are acquired at consistent aircraft operating configurations including bleed air off-take, cabin air recirculation and anti ice. There are essentially two different systems for data acquisition, manual and automated, with the following general requirements to ensure reliability and consistency.
http://www.casa.gov.au/scripts/nc.dll?WCMS:STANDARD::pc=PC_93093[7/11/2013 5:31:02 PM]
Civil Aviation Safety Authority - AWB 72-1 - Engine Condition Trend Monitoring (ECTM)
Data Entry
In the manual data acquisition arrangement, data entry constitutes an area of potential errors and needs special focus as identified by the following elements. The software should be of the latest revision status and, along with the relevant users manual, should be managed as a controlled technical document. The ECTM data is usually identified by aircraft registration and it is important that this is transferred to engine serial number specific data at the time of data entry. There should be arrangements for timely incorporation of engine change data into the ECTM data. There should be arrangements to ensure that relevant data for loan and lease engines are entered into the system as part of engine fleet induction procedure. Inaccurate and missing data can impede analysis and there should be arrangements for feed back to the data acquisition area and corrective action. Appropriate back-up systems for electronic data should be provided to avoid inadvertent data loss.
Data Analysis
Competent and timely analysis of data is central to the identification of engine deterioration.
Civil Aviation Safety Authority - AWB 72-1 - Engine Condition Trend Monitoring (ECTM)
The ECTM analysis is to be carried out by a person with adequate experience and familiarity with turbine engines who has undergone the ECTM training provided by the manufacturer. On the job training when carried out in a structured manner is adequate, provided the training details are appropriately documented. Data analysis is to be carried out at intervals specified by the manufacturer and the findings recorded. Policies on resetting the base lines, acceptable ECTM data for loan/lease engines etc should be specified. If the ECTM analysis is contracted out, the communication of analysis findings, feedback and measures to ensure the quality of ECTM must be documented. The data analysis should include review of engine parameter exceedances where such data is available from automatic data acquisition systems.
Follow-up Actions
The objective of ECTM is to take appropriate corrective action when required based on the trend data. The following elements are to be considered to achieve this objective. There should be clear procedures on how the recommended corrective actions emerging from the ECTM analysis are to be communicated for maintenance action. There should be feed back on when the recommended actions have been carried out. The corrective actions, when carried out are to be recorded and the impact of these actions assessed.
Summary
This AWB has identified several sub-systems and their elements that form part of the ECTM system. To ensure a reliable and robust ECTM system, it is important that elements identified in this AWB are elaborated and specified along with other relevant details in a system of maintenance. Accurate and timely trend analysis is a fundamental part of a gas turbine engine management program that can enable adverse trends in engine performance parameters to be detected early and corrective actions to be taken. An accurate parameter history is also useful when determining workscopes during engine shop visits.
References
1. Pratt and Whitney Canada, Service Information letter PT6A-122, New generation ECTM - WebECTM, 26 September 2003. 2. Australian Transport Safety Bureau, Report 200105618. 3. Approved Single Engine Turbine Powered Aircraft (ASETPA), CASA AAC 1-116, 2000.
Enquiries
Enquiries with regard to the content of Airworthiness Bulletins should be made via the direct link e-mail
http://www.casa.gov.au/scripts/nc.dll?WCMS:STANDARD::pc=PC_93093[7/11/2013 5:31:02 PM]
Civil Aviation Safety Authority - AWB 72-1 - Engine Condition Trend Monitoring (ECTM)
address included on the Airworthiness Bulletin web site, AirworthinessBulletin@casa.gov.au or in writing to: Airworthiness Standards Branch, GPO Box 2005, Canberra, ACT, 2601
Commonwealth of Australia 2002
CASA online store Manuals and forms Regulations and Policy Contact us Site Feedback Site Map CASA Industry Complaints Commissioner Freedom of information Copyright Privacy Site help Mailing lists