The SavvyAnalysis Report Card and Trend Analysis reports are infographics containing graphical visualizations of your aircraft and engine’s performance, including the values of important operating parameters during recent flights. The reports compare your aircraft’s performance to that of other aircraft in your aircraft’s cohort and include operational and maintenance recommendations. The reports are produced entirely by our proprietary analytical software, and are based on the data you and others have uploaded to our database of almost two million flights.
Who has access to Report Cards and Trend Analysis?
Report Cards and Trend Analysis reports are provided to aircraft that:
- Are subscribed to our SavvyAnalysis Pro, SavvyQA or SavvyMx services, and
- Are members of a supported aircraft and engine model cohort. Here is a list of cohorts currently being supported. We plan to add support for as many aircraft and engine models as possible.
For SavvyMx and SavvyQA clients, please see special access instructions below.
The Report Card presents a visual summary of your aircraft’s and your cohort’s performance measures using the “thermometer” paradigm shown below.
The Report Card “thermometer” shows the minimum, maximum and median values of each of your aircraft’s performance measures (e.g. CHT, oil pressures, etc.) as a blue line overlaid on a depiction of the performance of aircraft in your cohort. The colored “thermometer” depicts the cohort values corresponding to the minimum, 25th percentile, median (50th percentile), 75th percentile and maximum. A description of each performance measure is included above the graphic, and recommendations and interpretations are shown below the graphic.
The Trend Analysis chart expands on the information contained in the Report Card. Rather than summarizing your aircraft’s performance measures as minimum, median and maximum values, the Trend Analysis chart plots each individual data point corresponding to each of your flights on a timeline. This allows us to analyze changes in the data for trends.
The timeline is shown on the horizontal axis at the bottom of the chart. The value of the performance measure for each flight is plotted as a blue diamond along the timeline. The vertical axis on the left side of the chart represents the values of the performance measure, in this case maximum CHT during cruise. The vertical axis on the right side of the chart shows the 25th percentile, median (50th percentile) and 75th percentile values of the performance measure for the cohort. A dark green line is depicted at the cohort median value, and the 25th to 75th percentile range of cohort values is represented by a green-filled band. A dark blue horizontal line represents the median value of the performance measure for your aircraft.
Are the trends in my data “real”?
Our Trend Analysis software performs a statistical test on your aircraft’s individual data points, testing whether an increasing or decreasing trend in the data over time is likely due to real underlying changes in the data, or rather a result of random variations. If the test shows a statistically significant increasing or decreasing trend (alpha=.05), a dotted blue line is drawn describing the increasing or decreasing trend. If the trend in the data values is not statistically significant, no dotted blue line is drawn and a message to that effect is included at the top of the chart.
Are all my flights included?
Report Cards , Trend Analysis reports and Alerts require a minimum of three qualified flights of your aircraft during the specified time period, or else the report will not be rendered.
Only flights having an identifiable cruise segment of at least a 10 minute duration, and a total duration of at least 40 minutes are included in the analysis. To identify the cruise segment we use altitude (or OAT as a surrogate for altitude if the engine monitor does not provide altitude) along with stable values of some mix of MAP, FF, RPM, IAS and EGT. If your engine monitor only records EGT and CHT we will not be able to identify the cruise segment.
I just uploaded a bunch of flights but can’t create a report!
When you upload data to our platform it has to be processed to calculate the information used in creating a Report Card or Trend Analysis report. We process new data once per hour, so it is not immediately available after download.
How reliable are Report Cards and Trend Analysis reports?
We work hard to make the reports as reliable as we can, but there are a number of factors which can cause results to be inaccurate. We caution our clients not to use the reports as the final authority on aircraft condition, and to always verify the results shown in the reports by other diagnostic means. Possible sources of inaccuracies in our reports are:
- The reports are only as good as the data coming from the engine monitor. If the monitor is incorrectly configured or a sensor (probe) is failing, the data can be inaccurate. Probe placement can also introduce variations in data values.
- Our users self-select their aircraft and engine model in their profiles. Mistakes are sometimes made which result in the aircraft’s data being compared with the wrong cohort, or flight data from an aircraft in a different cohort being included improperly.
- In some cases the aircraft in a single cohort might include different models of aircraft and engine. This might occur if a single cohort includes slightly different variants of the same aircraft model, or includes aircraft with upgraded engines. We do our best to group aircraft together in the best way, but sometimes variations are inevitable.
- We’d like to think our software is perfect. It isn’t. We occasionally have bugs that can affect the accuracy of the results. And often our software is attempting to heuristically infer a condition indirectly from the data (e.g. the cruise segment of the flight.) On occasion these algorithms might produce an inaccurate result.
If you have questions regarding the appropriate cohort for your aircraft, whether your cohort contains aircraft different from yours, or any other questions regarding possible inaccuracies in our reports, feel free to contact us.
We welcome your comments, suggestions and questions. Please contact us at firstname.lastname@example.org