FAA Powerplant Written Practice Test

Which statement is not true regarding turbine engine oil analysis programs?

1. First oil sample analysis is generally accurate

2. Sample analysis helps identify contaminants

3. Regular analysis can predict oil life

4. Trend forecasts may be inaccurate without multiple samples

The correct answer is: First oil sample analysis is generally accurate

The statement that the first oil sample analysis is generally accurate is not true because initial samples may not provide a complete picture of the oil’s condition. The first sample can be influenced by residual oils from manufacturing or installation processes, which may not represent the engine's actual operating condition. Over time, as more samples are taken, trends and patterns become clearer, allowing for more accurate assessments regarding the engine's health and oil quality. Regular oil analysis programs rely on continuous data collection, enabling the identification of contaminants and wear metals, which is crucial for predicting oil life and assessing overall engine condition. Trend forecasts improve with additional samples, as they help establish baseline values and monitor changes over time, which enhances the reliability of the conclusions drawn about oil performance and potential maintenance actions.