Actual Accuracy in Flight Data Collection and Analysis

In aerospace applications it is often vital to understand what is happening when analyzing sound and vibration data and what total accuracy one receives. The tradition has been to spend money on yearly calibration of sensors and part of the measurement equipment, but not on the software used for analysis of the data collected by these sensors. While the sensors might be accurate to a percentage level, erroneous analysis procedures can give arbitrarily high errors! Usually, there is no “calibration option” or “benchmark” for sound and vibration analysis software. This paper will present some common pitfalls and what can happen if the user is not aware how the software is handling the data, or even worse, the code was not correctly implemented in the first place. Some real life examples of the latter and suggested solutions to avoid such harmful situations will be presented. Also, some good guidelines for aerospace data collection and analysis, with focus on sound and vibration applications, will be discussed.