Approximately 10,000, 10-ton, 4-wheel, 2-truck, coal mine cars are in general service in U.S. mines. None are equipped with an automatic braking system. Very few are equipped with hand or parking brakes. The report compiles physical specification of cars of major car manufacturers, and develops a composite clearance diagram. It then discusses a pneumatic system employing truck components for an automatic system that could be used as an add-on unit. The components are listed and priced and a schematic circuit is developed for the system. Recommendations as to future programing are made.