| Chicago Burlington & Quincy Railroad 4-6-2 class S-1 2806 at Philadelphia, Pennsylvania, sometime in 1906, photo by Baldwin Locomotive Works, Chuck Zeiler collection. This locomotive was built in 1906 by Baldwin (c/n 28298), one of the first Pacific-types on the Burlington Route. It was rebuilt to S-1-A in 1926 and retired September 1939. The following is from the book, Steam Locomotives Of The Burlington Route, by Bernard G. Corbin and William F. Kerka: The Class S-1 Baldwin-built Pacifics were a direct development of the R-5 Prairies. Thirty S-1 engines, No. 2800-2829, made their appearance on the road in 1906, followed by fifteen Schenectady-built engines, No. 2830-2844 in 1907. The boilers of the S-1 types were similiar to the R-5 Prairies, except that the tube length was increased by 24". Although the driving wheel diameter was increased to 74" on the S-1 engines, the cylinders as well as the driving and trailing wheel axle journals were of the same dimensions as the R-5. This permitted interchangability of parts in the machinery and running gear of the Pacifics and Prairie-type engines. During the mid-1920's, the great majority of the S-1 and S-2 locomotives were rebuilt and reclassed as S-1A and S-2A respectively. Among the changes made during this rebuilding period were the application of new cylinders and accessories, new main frames and frame crossties, application of Schmidt-type superheater, new tube sheets and tubes to suit the superheater, new Walschaerts valve gear, new steam pipes, new front deck plate, application of cross-compound air pumps, new main axles and main driving boxes, and the application of either Worthington or Elesco feedwater heating systems. Some of the rebuilt engines were fitted with Delta-B trailing trucks having Franklin boosters. Most of the tenders on the S-1A and S-2A engines were also rebuilt, and four-wheel Commonwealth trucks were substituted for the pedestal type. Some of the Pacifics spent their last days in suburban service around the Chicago area. By the end of 1950 just about all had been retired. |