FAA Powerplant Written Practice Test

In a spectrometric oil analysis, which indicator is of the greatest concern?

1. An indicator with a steady reading

2. An indicator which has fallen since the last analysis

3. An indicator which has risen at a faster rate than in its last analysis

4. An indicator that is at normal operating levels

The correct answer is: An indicator which has risen at a faster rate than in its last analysis

In spectrometric oil analysis, the focus is on identifying wear patterns and degradation within the engine components through the analysis of oil samples. The greatest concern arises when an indicator has risen at a faster rate than in the last analysis. This significant increase often signals that there may be an accelerated wear process occurring within the engine. Such an increase can indicate potential issues like excessive friction, misalignment, or component failure, which could compromise the engine's performance or reliability. Monitoring trends is crucial, and a rapid rise in certain wear metal indicators often necessitates further investigation and potentially remedial action to prevent more significant problems. Other scenarios such as steady readings or indicators at normal operating levels typically suggest that the engine components are functioning within acceptable limits, and a decrease from the last analysis may not indicate immediate concern unless it correlates with specific known issues. Therefore, the focus on a rapidly rising indicator highlights a proactive approach to maintenance and safety within aviation engines.