Document provides information on how military/commercial/gas turbine engine test cell/system users may benefit from this unique Coanda//refraction concept. The information contains several factors which are considered essential for understanding the practical technical aspects of the concept. These are: a. operation need; b. concept definition; c. developmental program; and d. program results. To present an advanced technology in suppression of gas turbine engine exhaust noise in ground run-up test cells/systems. The discussion herein is limited to turbojet and turbofan type engines, although the concept is equally applicable to turboshaft and turboprop types. To explain specific applications of this technique in various types of test cells.