While the USRA Heavy Pacific was designed for express trains, the Light Pacific had a six inch smaller driver diameter and was primarily intended for passenger trains. With a maximum axle load of 54,000 pounds, it was also suitable for branch lines. Its usual services included hauling ten to twelve coaches at a speed of 70 to 80 mph (113 to 129 km/h). 106 of the original model were built, of which 70 went to the Atlantic Coast Line and were designated class P-5-A. 30 went to the Baltimore & Ohio and six to the Louisville & Nashville. Later copies also included 165 P-5-B for the ACL, while other railroads only procured smaller numbers.