Engine and Transmission Monitoring
Engine and Transmission Monitoring tests how you use indications and trends to detect degradation before a failure. The exam expects you to distinguish a transient from a trend, and a sensor fault from a real exceedance.
Core rules
- Primary engine parameters: N1, N2, TGT, torque, fuel flow, oil pressure and temperature.
- Transmission parameters: oil pressure and temperature, chip detectors, vibration and HUMS data.
- Trend monitoring compares parameters at a fixed reference such as torque or N1 over time.
- A single exceedance is an event; a gradual shift is degradation.
- Cross-check parameters: a TGT rise with no fuel flow change may be sensor error; with higher fuel flow it may be fouling or hot section distress.
- Exceedance recorders and FADEC fault logs must be downloaded and preserved.
Worked example
At 80% torque, baseline TGT is 780°C and fuel flow 280 kg/h. After 100 hours, at the same torque, TGT is 810°C and fuel flow 305 kg/h, while N1 is slightly higher. The consistent rise in fuel flow and TGT suggests compressor fouling or a small hot-section deterioration, not a single faulty probe. A probe fault would usually affect one channel or produce an implausible step. The action is trend review, borescope and performance check per the maintenance manual.
Traps
- Chasing a single high reading without checking trend and cross-parameters.
- Ignoring a slow TGT drift because it is within limits.
- Assuming a chip warning is a sensor fault.
- Not recording exceedances.
- Comparing readings at different torque or ambient conditions.