Near-field sonic boom test on two low-boom configurations using multiple measurement techniques at NASA Ames

A sonic boom wind tunnel test was conducted in September 2008 on two low-boom aircraft configurations in the NASA Ames 9- by 7-Foot Supersonic Wind Tunnel. The purpose of the test was to evaluate two new sonic boom pressure rails as an alternative pressure signature measurement technique to a traditional method using single probes, and to compare single-probe results with past tests. The two rails were each designed to capture an entire model signature in one data point, using a single row of pressure orifices over lengths of either 20 or 48 inches. The rails were far more productive than the probes in terms of time to measure a signature, but there were issues with both methods in terms of data quality. The models used for generating the signatures were low-boom supersonic aircraft configurations designed by NASA Ames Research Center and Gulfstream Aerospace Corporation. The test results showed that fairly good matches were obtained between the pressure rails and the single-probe data, as well as in tunnel-to-tunnel comparisons, though variations in the tunnel flow and excessive freestream humidity adversely affected the data quality at times.