Source and Radiation Properties of an Installed GE F404 Engine: An Overview of Findings

Because their high-intensity sound fields pose hearing loss risk to personnel and increased community annoyance, high-performance military aircraft noise remains an important area of study. To help address these concerns, Brigham Young University has been analyzing noise from a T-7A-installed F404 engine. This paper presents an overview of key findings related to source characteristics and radiation properties and their connection to current jet noise models – both qualitative and quantitative. Included are three-source similarity spectrum decompositions, a sound power and acoustic efficiency analysis, an examination of convective Mach number effects on the radiated directivity, and holography and beamforming-based source description. This paper summarizes new understanding of tactical jet noise radiation characteristics.