1. Date of download: 7/10/2016 Copyright © ASME. All rights reserved. From: Experience With Gas Path Analysis for On-Wing Turbofan Condition Monitoring J. Eng. Gas Turbines Power. 2013;136(1):011204-011204-8. doi:10.1115/1.4025347 Sensor locations in the GE CF6-80C2 turbofan engine Figure Legend:

2. Date of download: 7/10/2016 Copyright © ASME. All rights reserved. From: Experience With Gas Path Analysis for On-Wing Turbofan Condition Monitoring J. Eng. Gas Turbines Power. 2013;136(1):011204-011204-8. doi:10.1115/1.4025347 Effects of increasing customer bleed flow on GPA results when these are not taken into account in the model Figure Legend:

3. Date of download: 7/10/2016 Copyright © ASME. All rights reserved. From: Experience With Gas Path Analysis for On-Wing Turbofan Condition Monitoring J. Eng. Gas Turbines Power. 2013;136(1):011204-011204-8. doi:10.1115/1.4025347 HPT efficiency condition deviations obtained from GPA with on-wing data for 100 consecutive takeoffs Figure Legend:

4. Date of download: 7/10/2016 Copyright © ASME. All rights reserved. From: Experience With Gas Path Analysis for On-Wing Turbofan Condition Monitoring J. Eng. Gas Turbines Power. 2013;136(1):011204-011204-8. doi:10.1115/1.4025347 HPT mass flow capacity condition deviations obtained from GPA with on-wing data for 100 consecutive takeoffs Figure Legend:

5. Date of download: 7/10/2016 Copyright © ASME. All rights reserved. From: Experience With Gas Path Analysis for On-Wing Turbofan Condition Monitoring J. Eng. Gas Turbines Power. 2013;136(1):011204-011204-8. doi:10.1115/1.4025347 Probability density function of the residual errors between the smoothed and observed value Figure Legend:

6. Date of download: 7/10/2016 Copyright © ASME. All rights reserved. From: Experience With Gas Path Analysis for On-Wing Turbofan Condition Monitoring J. Eng. Gas Turbines Power. 2013;136(1):011204-011204-8. doi:10.1115/1.4025347 Hot day exhaust gas temperature margin trend from approximately 600 consecutive takeoff snapshots Figure Legend:

7. Date of download: 7/10/2016 Copyright © ASME. All rights reserved. From: Experience With Gas Path Analysis for On-Wing Turbofan Condition Monitoring J. Eng. Gas Turbines Power. 2013;136(1):011204-011204-8. doi:10.1115/1.4025347 HPC efficiency deviation trend. An exponential weighted moving average (EWMA) is used to represent a smoothed trend. Figure Legend:

8. Date of download: 7/10/2016 Copyright © ASME. All rights reserved. From: Experience With Gas Path Analysis for On-Wing Turbofan Condition Monitoring J. Eng. Gas Turbines Power. 2013;136(1):011204-011204-8. doi:10.1115/1.4025347 High pressure turbine efficiency deviation trend Figure Legend:

9. Date of download: 7/10/2016 Copyright © ASME. All rights reserved. From: Experience With Gas Path Analysis for On-Wing Turbofan Condition Monitoring J. Eng. Gas Turbines Power. 2013;136(1):011204-011204-8. doi:10.1115/1.4025347 Low pressure turbine flow capacity deviation trend Figure Legend:

10. Date of download: 7/10/2016 Copyright © ASME. All rights reserved. From: Experience With Gas Path Analysis for On-Wing Turbofan Condition Monitoring J. Eng. Gas Turbines Power. 2013;136(1):011204-011204-8. doi:10.1115/1.4025347 Hot day exhaust gas temperature margin trend from approximately 500 consecutive takeoff snapshots. The arrows indicate the observed EGT hot day margin shifts. Figure Legend:

11. Date of download: 7/10/2016 Copyright © ASME. All rights reserved. From: Experience With Gas Path Analysis for On-Wing Turbofan Condition Monitoring J. Eng. Gas Turbines Power. 2013;136(1):011204-011204-8. doi:10.1115/1.4025347 Corrected Tt25 temperature trend Figure Legend:

12. Date of download: 7/10/2016 Copyright © ASME. All rights reserved. From: Experience With Gas Path Analysis for On-Wing Turbofan Condition Monitoring J. Eng. Gas Turbines Power. 2013;136(1):011204-011204-8. doi:10.1115/1.4025347 Corrected Tt45 temperature trend Figure Legend:

13. Date of download: 7/10/2016 Copyright © ASME. All rights reserved. From: Experience With Gas Path Analysis for On-Wing Turbofan Condition Monitoring J. Eng. Gas Turbines Power. 2013;136(1):011204-011204-8. doi:10.1115/1.4025347 Corrected Tt5 temperature trend Figure Legend:

14. Date of download: 7/10/2016 Copyright © ASME. All rights reserved. From: Experience With Gas Path Analysis for On-Wing Turbofan Condition Monitoring J. Eng. Gas Turbines Power. 2013;136(1):011204-011204-8. doi:10.1115/1.4025347 Corrected Pt25 pressure trend Figure Legend:

15. Date of download: 7/10/2016 Copyright © ASME. All rights reserved. From: Experience With Gas Path Analysis for On-Wing Turbofan Condition Monitoring J. Eng. Gas Turbines Power. 2013;136(1):011204-011204-8. doi:10.1115/1.4025347 Corrected Ps3 pressure trend Figure Legend:

16. Date of download: 7/10/2016 Copyright © ASME. All rights reserved. From: Experience With Gas Path Analysis for On-Wing Turbofan Condition Monitoring J. Eng. Gas Turbines Power. 2013;136(1):011204-011204-8. doi:10.1115/1.4025347 Corrected Pt45 pressure trend Figure Legend:

17. Date of download: 7/10/2016 Copyright © ASME. All rights reserved. From: Experience With Gas Path Analysis for On-Wing Turbofan Condition Monitoring J. Eng. Gas Turbines Power. 2013;136(1):011204-011204-8. doi:10.1115/1.4025347 (a) Corrected shaft speed trends for the N1 shaft and (b) the N2 shaft Figure Legend:

18. Date of download: 7/10/2016 Copyright © ASME. All rights reserved. From: Experience With Gas Path Analysis for On-Wing Turbofan Condition Monitoring J. Eng. Gas Turbines Power. 2013;136(1):011204-011204-8. doi:10.1115/1.4025347 This figure shows the original Pt25 parameter data, including the downward shift, and the data corrected with the offset value Figure Legend:

19. Date of download: 7/10/2016 Copyright © ASME. All rights reserved. From: Experience With Gas Path Analysis for On-Wing Turbofan Condition Monitoring J. Eng. Gas Turbines Power. 2013;136(1):011204-011204-8. doi:10.1115/1.4025347 (a) Estimated efficiency deviation and (b) flow capacity deviation for the fan bypass Figure Legend:

20. Date of download: 7/10/2016 Copyright © ASME. All rights reserved. From: Experience With Gas Path Analysis for On-Wing Turbofan Condition Monitoring J. Eng. Gas Turbines Power. 2013;136(1):011204-011204-8. doi:10.1115/1.4025347 (a) Estimated efficiency deviation and (b) flow capacity deviation for the combined fan core and booster Figure Legend:

21. Date of download: 7/10/2016 Copyright © ASME. All rights reserved. From: Experience With Gas Path Analysis for On-Wing Turbofan Condition Monitoring J. Eng. Gas Turbines Power. 2013;136(1):011204-011204-8. doi:10.1115/1.4025347 (a) Estimated efficiency deviation and (b) flow capacity deviation for the high pressure compressor Figure Legend:

22. Date of download: 7/10/2016 Copyright © ASME. All rights reserved. From: Experience With Gas Path Analysis for On-Wing Turbofan Condition Monitoring J. Eng. Gas Turbines Power. 2013;136(1):011204-011204-8. doi:10.1115/1.4025347 (a) Estimated efficiency deviation and (b) flow capacity deviation for the high pressure turbine Figure Legend:

23. Date of download: 7/10/2016 Copyright © ASME. All rights reserved. From: Experience With Gas Path Analysis for On-Wing Turbofan Condition Monitoring J. Eng. Gas Turbines Power. 2013;136(1):011204-011204-8. doi:10.1115/1.4025347 (a) Estimated efficiency deviation and (b) flow capacity deviation for the low pressure turbine Figure Legend: