Calculation of Remaining Engine Life
The display below depicts a trend for an engine condition being monitored. The blue trend line represents the value of the figure of merit computed from long-term data acquisition, using data collected over the last 24 runs. The dashed green line represents the short-term trend of the figure of merit (from data collected over the current run). Because the long-term trend uses much more data, it is more stable. The short-term trend represents the most current condition, although it has much more uncertainty. The uncertainty in the short-term trend line is shown using the dashed yellow lines. The uncertainty increases the farther out one predicts performance. If the trend line intersects the fault threshold (red horizontal line) within a prescribed time period (such as 8 hours ahead), a fault may be predicted. The actual prediction method employed in REDI-PRO is more sophisticated than comparing short and long-term trends; more information is available in the description and documentation of the Life Extension Analysis and Prognostics Project in the Related Research section of this site.