the cost of the s1 was $669,780.00, equal to $ today. which was over twice the cost of a prr t1 4-4-4-4 (#6111 cost $310,676). no. 6100 was completed at altoona on dec.21, 1938 without streamlined casing. on the same day, it made its first road test with two cars running backward to huntingdon and returned to altoona at speeds up to mph. during the run, it was stopped and checked for overhang on all tight curves. assistant chief of motive power-locomotive carleton k. steins (1891-1973) noted superior riding and steaming qualities. during another pre-service road test, the s1 was clocked at towing 90 freight cars.