TetrUSS is a suite of computer programs used for fluid dynamics and aerodynamics analysis and design. The TetrUSS system was developed at NASA Langley Research Center during the 1990s to bring the state-of-the-art in computational fluid dynamics (CFD) to a higher level of utility, and is geared towards novices and experts alike. The software, originally developed for NASA internal applications, has gradually evolved into an efficient and versatile CFD tool used by engineers and scientists throughout the nation. TetrUSS has been employed in major NASA research programs such as High Speed Research / High Speed Civil Transport, Hyper-X, Abrupt Wing Stall, Mars Scout, Joint Strike Fighter, and many other smaller projects. The software is widely used in other government organizations, the aerospace industry, academia, and non-aerospace industries such as automotive, bio-medical, and civil engineering. TetrUSS was the recipient of the prestigious NASA Software of the Year award in 1996.

TetrUSS for Mac OS X is a native port of the original TetrUSS CFD software, and was developed by NASA Langley Research Center and the Air Force Research Laboratory . This CFD system consists of GridToolCocoa, VGRID OpenGL, POSTGRID OpenGL, USM3D, and various tools and utilities. While TetrUSS for Mac OS X is heavily based on the original SGI software (and thus will be familiar to existing TetrUSS users), numerous technologies in Mac OS X have been leveraged to improve performance, productivity, and ease of use.

TetrUSS is available free-of-charge to U.S. entities, citizens, and permanent residents. In addition, a free 1-week TetrUSS training course is available monthly at NASA Langley Research Center, and is strongly recommended.