Union Pacific's Baldwin AS-616

by Don Strack

(This article is an updated and expanded version of an article published in "The Streamliner", Volume 12, Number 4, Fall 1998)

In the period of 1940 to 1980, and before the mergers of the 1980s and 1990s, Union Pacific operated a total fleet of 302 yard switching locomotives. This fleet included examples of locomotives from all of the major manufacturers, including General Motors' Electro Motive Corporation (later Division, or simply, EMD), American Locomotive Company (Alco), Fairbanks-Morse Company, General Electric, and Baldwin Locomotive Works (later Baldwin-Lima-Hamilton). Included in the totals from Baldwin were six examples of their AS-616 road switching locomotive, which UP assigned almost solely to heavy terminal switching service.

The six new AS-616s for UP were delivered in December 1951 and January 1952 wearing UP's yellow and gray paint scheme, and were assigned road numbers D.S. 1260 - D.S. 1265. The D.S. designation meant Diesel Switch, and was used as an aid to dispatchers and other personnel as they assigned internal combustion motive power, versus steam motive power, to switching and local service. The D.S. designation was removed during late 1953. The long hood end was designated as the front on these units, and all other UP road switchers, until the arrival of the GP9s in 1954.

Although most of the AS-616s were purchased as heavy terminal switchers, at least two were purchased as road switchers, and they were the last of the railroad's sampling of the road switcher designs offered by the various builders, which included Alco, Fairbanks-Morse, and Baldwin. The railroad purchased five Alco RS-2s (UP 1191-1195, later 1291-1295) in 1947-1949; 11 H20-44s from Fairbanks-Morse (UP 1360-1370) in 1947; 11 Alco RSC-2s (UP 1180-1190, later 1280-1290) in 1948; five F-M H15-44s (UP 1325-1329) in 1948; a single Baldwin DRS-6-4-1500 (UP 1250), also in 1948; and three F-M H16-44s (UP 1340-1342) in 1950. This total fleet of 36 units (not counting the AS-616s) comprised UP's entire diesel road switcher fleet for almost another three years, until the arrival of the 10 SD7s and 30 GP7s from EMD in 1953, and 170 GP9s and 75 GP9Bs in 1954.

During the early years of steam's final decade on UP, the railroad tried many assignments for its new diesel locomotives, searching for the best method to take advantage of the diesel-electric's economies. One example is the use of the AS-616s as heavy switchers, rather than as road switchers. Another was the use of EMD's TR5 heavy switcher as branchline power, and as helper locomotives in California. UP also regularly assigned end-cab yard switchers to local and branchline service, at times equipping the units with train indicator boards and road-service pilots.

The Baldwin-Lima-Hamilton Corporation, of Eddystone, Pa. (changed from Baldwin Locomotive Works in 1950), built 168 examples of its 1600 horsepower, six-axle AS-616 road switchers between 1950 and 1954. Union Pacific's six AS-616s had construction serial numbers of 75185-75190, and were part of the 63 AS-616s built during 1951.

These six new locomotives for UP were built using Baldwin's low carbody and Commonwealth cast trucks, and were equipped with Baldwin's eight-cylinder 608A SC engine, and 63:15 gear ratio on their six Westinghouse 370 traction motors. In a later variation of the AS-616 design, Baldwin was forced to re-design their carbody, making it higher (even with the cab roof), to allow use of General Electric electrical gear due to Westinghouse's exit of the locomotive electrical gear market. This design change also included a change in truck design, from the earlier General Steel Castings - Commonwealth truck to the later built-up truck design, with drop equalizers.

These six heavy switchers were the last Baldwin diesels purchased by UP, and were six of a total Baldwin fleet of 18 units. During World War II, Union Pacific had received six of Baldwin's earlier VO-1000 end-cab switcher in 1943 and 1944, numbered as UP 1055-1060 and later as UP 1200-1205. These had been purchased under the mandate of the War Production Board in lieu of UP's first choice, the EMD NW-2. In 1948, UP received five of the DS-4-4-1000, which in 1946 had replaced the VO-1000 in Baldwin's catalog. These five DS-4-4-1000s were numbered as UP 1206-1210.

The first examples of the new AS-616 (All Service, 6 axles, 1600 horsepower) locomotive were completed in 1951 by the new Baldwin-Lima-Hamilton company, as a continuation of the earlier DRS-6-4-1500 (Diesel Road Switch, 6 axles, 4 axles powered, 1500 horsepower). In 1948, Union Pacific had purchased a single DRS-6-4-1500. This earlier model, completed as a demonstrator unit in November 1946, concurrent with deliveries to Columbus & Greenville and export units for Algeria and Morocco, was placed in service as Baldwin's demonstrator number 1500, which UP purchased in January 1948 as its own number D.S.1250. This single unit was different in appearance from UP's six AS-616s. The most obvious of these differences included a stepped cast frame, and the location of the radiator intake: low on the earlier model, and mid-way up the car body on the later AS-616 design. The unit was also equipped with a steam generator and a built-up, slatted pilot. UP 1250 also differed from the later AS-616s because of its A1A trucks (an unpowered idler axle between two powered axles), compared to the AS-616's C trucks (three powered axles). It was assigned to branch line passenger service between Walla Walla and Spokane, Washington, from the time of its delivery in 1948 until its retirement in August 1962. According to Gary and Stephen Dolzall in their Diesels From Eddystone, after its retirement in 1962, the unit sat in the Omaha dead line for four years without any interested buyers because it had been modified with EMD electrical components and extensively re-wired. It was finally sold to Industrial Maintenance Service of Hammond, Ind., in July 1966, and scrapped five years later, in 1971, by Pielet Brothers of McCook, Illinois.

The early versions of the AS-616, including UP's six units, included what has been called "thin frames" and "thick frames." This difference in frame side member thickness was to allow additional ballast for heavier locomotives. Some were built for light duty branch line service and included a thin side frame member. Others, such as UP's six units which were ballasted to 326,800 pounds, needed as much additional weight as possible, and were built with thick side frame members, with cut outs for the truck-mounted brake cylinders.

UP needed heavy switchers for its new hump yards in Pocatello (opened in 1947) and North Platte (opened in 1948), and for the heavy flat switching for Ogden Union Railway & Depot in Ogden, Utah (expanded in 1943), and these new AS-616s were purchased specifically for use as switchers in these terminal yards. Until this time, UP had been using single and double NW2s, along with F-M H15-44s at Pocatello, as their hump yard motive power. The railroad had been impressed by demonstrations of the heavy hauling capabilities of Baldwin's Westinghouse electrical gear, and, with the improved diesel engine in the AS-616, saw a design that would fill its needs for a heavy switcher.

Railroad records show that two of the new AS-616s (UP 1260 and 1261) were sent to the Pocatello hump yard. Two others (UP 1262 and 1263) were tested very briefly in branch line service in Kansas and Nebraska, then were assigned to the hump yard in North Platte.

The final two units, UP 1264 and 1265, were immediately leased to Ogden Union Railway & Depot Co. and assigned to Ogden upon their delivery, with Ogden remaining as their home terminal throughout most of their 17-year careers. A regular assignment in Ogden called for the two units, nicknamed "Mike and Ike," to pull entire trains for interchange between SP and UP. The route was over the mile or so of trackage that separated the two Ogden Union Railway & Depot (OUR&D) yards, the main yard situated between 20th Street and 29th Street, and Riverdale Yard situated between 31st Street and Riverdale Road. Ogden's Riverdale yard is on a slight 0.3 percent (four inches rise in 100 feet of distance) down grade from the yard's east end at Riverdale Road to 31st Street. This slight grade has always been a concern in the yard's operation from the time of its opening in 1943, and the switch crews appreciated the extra horsepower and additional axles of the AS-616s. During the 1970s, SD24s were used, and today (in 1998), the yard is operated with SD40-2s for the same reason.

During the spring and summer of 1954, UP 1264 was used in the Manhattan, Kansas, area on Trains 173 and 174. Tom Lee related the following about 1264's use in Kansas:

Normal power for those trains during steam days was either a 1990 or 2100 class 2-8-2. The northbound #173 usually had a pretty fair sized train, 40 to 60 cars, as the central Kansas traffic, including the oil business off the McPherson Branch, destined for points north and west, was routed to Marysville rather than Salina west.

One of the Baldwin 1000 HP yard switchers was used in Marysville for awhile in the early '50s and made a trial run on the branch trains. It was too light to consistently handle #173 over the grades just north of Manhattan and north of Blue Rapids. I first saw the 1264 on #173 in mid April 1954, and it was used on these trains much of the time through September 1954, when several of the new GP9s in the 205-244 order were assigned to the Kansas Division. By November the Geeps were being used regularly on the branch followed the next summer by an occasional GP7, Alco road switchers in the 1280 and 1291 series, and other m.u. [multiple unit] combinations of yard switchers before [returning] back to GP9s.

From company records, here are the known assignments. UP 1260 worked at Pocatello until 1962, then was moved to Omaha. UP 1261 worked in Pocatello throughout its entire career, until its retirement in December 1969 (both units were replaced by Century 630s, 2906 and 2907). UP 1262 worked in Ogden from February 1964 until 1968, with a brief stint in Omaha during 1966. UP 1265 worked in Ogden from February 1964 to its retirement in May 1968.

Their use in hump service in North Platte was remembered by Art Stensvad, a UP engineer on the Third District out of North Platte until he retired in 1983:

We had usually only two assigned to North Platte yards, the 1262 and 1263. later, the 1264 replaced the 1262 which was damaged and sent to Omaha Shops. They were primarily brought here to use as hump pushers, one working the early shift (7-3-11) and the other working the 8 to 4, or Midnight shift. They did the job well and had an exceptionally good hump control with a large wheel to adjust the humping speed and was a lot easier for the hoghead to set and watch. The engines could be overloaded and UP did just that. When the train was normal, you could not ask for a better engine.

When the new Alcos came, they were put on the hill and the AS-616s were sent down below to trim the trains. They were a little stiff and going into the PFE cleaning track, they would sometimes derail. The engines were finally replaced by Alcos and sent to Omaha for disposal. they did not have the best cab heaters and were cold during the real bitter weather. Doors were narrow and a person had to be careful or you would bump your head. There were a good engine as far as the hoghead was concerned, until they wore out and UP did not put a lot of repairs in them.

Although tested in local and branch line service in Nebraska and Kansas, UP's AS-616s were used by the railroad usually as heavy switchers, and the units' final years found them in heavy transfer switching service at Ogden and Pocatello. They were also used at North Platte and in Omaha. The units at Pocatello and North Platte were displaced by 2900-class ALCO Century 630s in 1967, and by early 1968, the entire fleet was gathered in the dead lines at Omaha. UP 1262, 1263, and 1264 were retired in April 1968, and UP 1265 soon followed in May. UP 1260 and 1261 were retired in January and December 1969 respectively. All were traded to EMD on new SD45s in 1968 and new DDA40Xs in 1969.


The author wishes to thank Gary Binder for his assistance in the preparation of this article. Gary has been gathering information on UP's AS-616s since 1987, including receiving correspondence on the subject from John Rieschl, Thomas Lee, and Arthur Stensvad. James Watson gladly allowed the author to use the photographs by Emil Albrecht from his collection.

Additional Reading

Dolzall, Gary W. and Stephen F. Dolzall Diesels From Eddystone: The Story Of Baldwin Diesel Locomotives (Kalmbach Books, 1984)

Kirkland, John F. The Diesel Builders, Volume Three, Baldwin Locomotive Works (Interurban Press, 1994)

Strack, Don Union Pacific Switchers and Slugs (Withers Publishing Co., 1996)

Strapac, Joseph A. Southern Pacific Review, 1983-1985 (Shade Tree Books and Pacific Coast Chapter, R&LHS, 1986)