GN S-2 Class - Great Northern Empire

S-2 Class 4-8-4 General Data

Built:

Between 2/1930 and 3/1930

Cylinders:

29"x29"

Engine weight:

420,900 lbs.

Builder:

Baldwin Locomotive Works

Driver diameter:

80"

Weight on drivers:

247,300 lbs.

Number built:

14 (#2 575-2588)

Boiler pressure:

Design: 225 psi.

Operating: 225 psi.

Tractive effort:

58,310 lbs.

In March and April of 1930 the Great Northern Railway received fourteen 4-8-4's from Baldwin, assigning them to the S-2 class and numbering them 2575 through 2588. Intended for Oriental Limited and Empire Builder duty they were assigned to the Montana division for service between Williston, ND and Havre, MT, and the Spokane division for service between Spokane, WA and Wenatchee, WA GN 1936 logo

The design of the S-2 Class 4-8-4 was somewhat of a departure from the traditional steam locomotive design on the Great Northern. Normally the GN preferred to equip its engines with a Belpaire type boiler, but in an effort to reduce weight, the S-2's were delivered with a radial stay boiler. The nickel-steel boiler tapered from a 85 1/4" diameter at the front, to a 94" diameter at the dome ring. It was constructed for a design and operating pressure of 225 psi. The boiler had a firebox measuring 138" long by 102" wide, designed to burn oil. A Walschaert type valve gear transmitted power from the 29" diameter by 29" stroke pistons to the drivers, which were 80" in diameter, the tallest on any Northern.

The S-2 came with a Vanderbilt type tender, which provided a capacity of 17,000 gallons of water and 5,800 gallons of oil. It was unique in being the only all-welded tender on the GN. This water-bottom tender had a Commonwealth cast-steel frame and rode on two 6-wheel cast steel trucks.

The total engine weight of the S-2 was 420,900 pounds, with 247,300 pounds on the drivers, providing a tractive effort of 58,300 pounds. This made the engines fast but a bit slippery in starting larger weights.

The S-2 engines were all delivered in the classic green paint scheme, except 2577 which carried a coat of light grey or aluminum paint on the boiler and cylinder jackets at delivery, most probably for photographic purposes. She was eventually repainted in Cascade green. All engines came with chrome plated cylinder covers and steam chest heads. By the 1950s all engines had received the more economical all-black paint scheme.

The only major rebuilding of this class was the replacement of the original friction bearings with Timken roller bearings in the 1940s. Some engines were temporarily converted to burn coal for a period in the late 1930s. Vestibule cabs were added to engines 2577 (in the early 1930s) and engines 2582, 2586, 2587 and 2588 (by the late 1940s).

S-2 engines were involved in two of the better-known accidents on the Great Northern. On August 9, 1945 engine 2588 was involved in the worst accident on the GN when it was on the point of the second section of the westbound Empire Builder. It rear-ended the first section at Michigan, ND which had stopped there due to a hotbox. The impact was so heavy that it split open the observation car, killing 34 people, and wounding 303. The ICC cited a failure to provide adequate protection for the preceding train as the cause.

Engine 2581 experienced a boiler explosion caused by a crown sheet failure due to a low water level at Crary, ND on January 9, 1947, killing the engineer, fireman and the Division Roadmaster who was riding in the cab. Following the accident 2581 was scrapped, having earned the questionable honor of being the last engine to experience a boiler explosion on the GN.



GN S-2 4-8-4 #2587 Summit, MT August 5, 1938

As the Great Northern dieselized, the S-2 lost its assignment on the Empire Builder and drew duty on less prestigious passenger runs and saw service in freight duty, where its passenger design proved to be rather unsuitable. All engines were retired by 1958, with some remaining in strategic storage until 1963. Only one S-2 survives today; 2584. She was retired in December of 1957. In 1958 it was decided to hold her for historical purposes. On May 15, 1964 she was put on display at the Havre, MT depot, where she is still residing today as a fond memory of the superb passenger steam power once used on the Great Northern Railway.

GNRHS Reference Sheet #152; Rear-End Collision - Two Passenger Trains, Michigan, North Dakota - August 9, 1945

GNRHS Reference Sheet #161; Crown Sheet Failure - Locomotive 2581 Crary, North Dakota - January 9, 1947

Click for map to tender #2575		Photos taken July 15, 2002
GN S-2 Class 2575 tender at Brooklyn Roundhouse Portland, OR