J2971_201908 Truck and Bus Aerodynamic Device and Concept Terminology

A required periodic Five-Year Review highlighted the need to add additional terminology and make revisions to existing definitions. This revision permitted reformatting the document to make future changes less labor intensive by removing redundant section numbering in place of just alphabetizing terms in the definitions section, a format change approved through SAE. Table A1, originally inserted as a graphic, was replaced with a text version of the table to allow editing. Minor spelling and phrasing corrections were done for consistency. New terms have been added: active and passive, multi-vehicle, porosity control, aero-elastic, synthetic jet, virtual, aero-stability, and aero-braking device or systems.