Preliminary Findings of In Situ EDR Standards Research

In response to industry recommendations, the Federal Aviation Administration (FAA) has conducted the Eddy Dissipation Rate (EDR) Standards Project to perform the research and analysis required to recommend in situ EDR performance standards.

The process employed by the project, leading to the development of these recommendations, involved the creation of wind datasets replicating real-world atmospheric conditions and the simulation of operational aircraft characteristics (e.g., sensor noise, electrical noise, avionics truncation, transfer functions, anti-aliasing). These artifacts constitute the inputs to operational in situ EDR algorithms on-board aircraft. There are varying implementations of in situ EDR using different computational algorithms, each employing dissimilar techniques, assumptions, and inputs from aircraft sensors and avionics. Based on the same algorithm input wind datasets, EDR ‘truth' data was derived. After performing pseudo operational runs simulating various turbulence conditions and comparing the results with the ‘truth' EDR, a statistical analysis was performed, providing the project with an assessment of today's in situ EDR system performance.

Today's operational performance was then compared with current and anticipated user performance objectives for in situ EDR, to formulate the in situ EDR performance recommendations contained in this paper.