Milwaukee Road class S3

The Milwaukee Road S3 Class was a class of 10 4-8-4 "Northern" type steam locomotives built by the American Locomotive Company in 1944 and operated by the Milwaukee Road until the mid 1950s. The locomotives saw service in pulling freight and passenger trains throughout the Milwaukee Road.

Milwaukee Road S3 class
MILW 265 on display in Milwaukee, Wisconsin in early 1966.
Type and origin Power type Steam Builder American Locomotive Company Order number S-1928 Serial number 71973–71982 Build date July–September 1944 Total produced 10
Specifications Configuration: ​  • Whyte 4-8-4  • UIC 2′D2′ h2 Gauge 4 ft 8+1⁄2 in (1,435 mm) standard gauge Leading dia. 36 in (914 mm) Driver dia. 74 in (1,880 mm) Trailing dia. 38 in (965 mm) (lead axle) 44 in (1,118 mm) (trail axle) Wheelbase Loco & tender: 95.54 ft (29.12 m) Length 109 ft 7+3⁄4 in (33.42 m) Height 15 ft 6 in (4.72 m) Axle load 64,825 lb (32.413 short tons) Adhesive weight 259,300 pounds (129.7 short tons) Loco weight 460,000 pounds (230 short tons) Tender weight 364,100 pounds (182.1 short tons) Total weight 824,100 pounds (412.1 short tons) Tender type Water-bottom Fuel type Coal Fuel capacity 25 short tons (23,000 kg) Water cap. 20,000 US gal (76,000 L; 17,000 imp gal) Firebox: ​  • Grate area 96.20 sq ft (8.937 m2) Boiler pressure 250 lbf/in2 (1.72 MPa) Safety valve Pop Cylinders Two Cylinder size 26 in × 32 in (660 mm × 813 mm) Valve gear Walschaert
Performance figures Maximum speed 100 mph (160 km/h) Power output 4,500 hp (3,400 kW) Tractive effort 62,119 lbf (276.32 kN) Factor of adh. 4.17
Career Operators Milwaukee Road Class S3 Numbers 260–269 Retired 1954-1956 Preserved Two (No. 261 and No. 265) Disposition Milwaukee Road 261 in operating condition Milwaukee 265 on display in Union, Illinois Remainder scrapped

Today, two S3s survive, No. 261 is in operating condition and No. 265 is on display in Union, Illinois.

History

The Milwaukee Road had acquired its first four-unit EMD FT diesel set in October 1941. It had managed to get a second in July 1943, but when it wanted more in 1944, it was only allocated six by the War Production Board. Instead, it was allocated ten Alco 4-8-4 locomotives. These were delivered in July and September 1944, and were classified as class S3 by the Milwaukee Road.^[1]

Design

Alco had drafted a compromise design, as the WPB has placed a moratorium on creating completely new designs. It was based on the frame of the Chicago, Rock Island and Pacific Railroad class R67B, mated to the boiler of the Delaware and Hudson Railway class K. The tender was a water-bottom type with a pair of six-wheel trucks.^[2] They were also fitted with an air horn.

The 96.20 square feet (8.937 m²) of coal-burning grate supplied heat the boiler which was pressed to 250 pounds per square inch (1.72 MPa). This supplied steam to the cylinders which had a bore of 26 inches (660 mm) and a stroke of 32 inches (813 mm). They were connected to the 74 inches (1,879.600 mm) diameter driving wheels by Walschaerts valve gear.

While they were smaller and less powerful than the Milwaukee's earlier class S2, they were comparable to road's first class of 4-8-4, the class S1 and were equipped with roller bearings.

Construction

All ten were built by Alco's Schenectady plant in July (7) and September 1944 (3). Alco assigned order number S-1928 and serial numbers 71973 through 71982.

Service

Initially they were used as freight locomotives, and only used on lines east of the electrified zone, being allocated to the Dubuque and Illinois Division (now the Canadian Pacific Kansas City Elgin Subdivision). As a consequence of the Korean War, additional locomotives were needed on the Idaho Division, so four locomotives (262, 263, 267 and 269) were converted to oil firing and sent west to work passenger and freight trains in the gap between the two electrified zones.^[1]

By March 1954, No. 260 had been transferred to the La Crosse and River Division, and 261 was on the Milwaukee Division; the other four coal-burners were still on the D&I Division, and the four oil-burners on the Idaho Division.^[3]

By December 1954, however, the Milwaukee was effectively dieselised. As the equipment trusts on the ten locomotives had yet to expire, they could not be scrapped or sold, so they were placed into storage – the Idaho four going to Tacoma.^[4]

Table of locomotives.^[5]

No.	Alco serial number	Built	Retired	Notes
260	71973	July 1944	December 1954
261	71974	July 1944	August 1956	Preserved
262	71975	July 1944	December 1954	Converted to burn oil
263	71976	July 1944	December 1954	Converted to burn oil
264	71977	July 1944	February 1956
265	71978	July 1944	September 1956	Preserved
266	71979	July 1944	February 1956
267	71980	September 1944	December 1954	Converted to burn oil
268	71981	September 1944	December 1954
269	71982	September 1944	December 1954	Converted to burn oil

Preservation

Milwaukee Road 261, the sole operational unit

Two S3s survived into preservation:

• Milwaukee Road 261 was retired in August 1956 and donated to the National Railroad Museum in Green Bay, Wisconsin in 1958. Today, the locomotive is owned, operated, and maintained by Minneapolis-based nonprofit organization Friends of the 261, which runs occasional and seasonal excursion trains using the locomotive.
• Milwaukee Road 265 was retired in September 1956 and donated to the city of Milwaukee, Wisconsin and sat on display until 1975. The locomotive was then moved to the Illinois Railway Museum in Union, Illinois where it currently resides.