BATES is an acronym for BAllistic Test and Evaluation System, which is a standardized system for measuring solid rocket propellant performance designed and developed by the United States Air Force Research Laboratory in 1959 through the early 1960s,[1] used for almost forty years thereafter, and again beginning in 2010.
According to this reference, a single propellant grain weighing 68 to 70 pounds was used in the original AFRL BATES motor design.
The first official description of the BATES system was published by and available from the Defense Technical Information Center (DTIC): “Development and Evaluation of the USAF Ballistic Test Evaluation System for Solid Rocket Propellants”.
[4] In 2016 the AIR FORCE published through DTIC an overview the included a summary of BATES use.
[5] In modern usage, BATES often refers to a type of solid-fuel rocket motor grain geometry.
Such grains are very easy to cast, while allowing for the user to configure a progressive, regressive, or neutral thrust curve by changing various dimensions.