Maine Central Railroad Class S locomotives were intended for heavy freight service. They were of

2-8-2 Under the Whyte notation for the classification of steam locomotives, represents the wheel arrangement of two leading wheels on one axle, usually in a leading truck, eight powered and coupled driving wheels on four axles and two trailing wheel ...

wheel arrangement in the Whyte notation, or " 1'D1' " in UIC classification. They replaced earlier class W

2-8-0 Under the Whyte notation for the classification of steam locomotives, represents the wheel arrangement of two leading wheels on one axle, usually in a leading truck, eight powered and coupled driving wheels on four axles, and no trailing wheels. ...

locomotives beginning in 1914. They were the largest and most modern steam freight locomotives built for Maine Central; although former

Boston and Maine Railroad The Boston and Maine Railroad was a U.S. Class I railroad in northern New England. Originally chartered in 1835, it became part of what was the Pan Am Railways network in 1983 (most of which was purchased by CSX in 2022). At the end of 1970, B ...

2-10-2 Under the Whyte notation for the classification of steam locomotives, represents the wheel arrangement of two leading wheels, ten powered and coupled driving wheels, and two trailing wheels. In the United States of America and elsewhere the is ...

s were later purchased to handle World War II freight traffic. Class S locomotives pulled freight trains over the main line between

Portland Portland most commonly refers to: * Portland, Oregon, the largest city in the state of Oregon, in the Pacific Northwest region of the United States * Portland, Maine, the largest city in the state of Maine, in the New England region of the northeas ...

and

Bangor, Maine Bangor ( ) is a city in the U.S. state of Maine and the county seat of Penobscot County. The city proper has a population of 31,753, making it the state's 3rd-largest settlement, behind Portland (68,408) and Lewiston (37,121). Modern Bangor ...

; and are best remembered for service on the Mountain Division from 1929, when the class X Mallet locomotives were scrapped, until replacement by

diesel locomotive A diesel locomotive is a type of railway locomotive in which the prime mover is a diesel engine. Several types of diesel locomotives have been developed, differing mainly in the means by which mechanical power is conveyed to the driving whee ...

s in the early 1950s.

Sub-classes

All were built in

American Locomotive Company The American Locomotive Company (often shortened to ALCO, ALCo or Alco) was an American manufacturer of locomotives, diesel generators, steel, and tanks that operated from 1901 to 1969. The company was formed by the merger of seven smaller locomo ...

's plant at Schenectady, New York and were numbered from 601 to 632 as delivered. Builders numbers 54571-54573 were delivered in 1914, 55020–55026 in 1915, 56502–56507 in 1916, and 57879–57882 in 1918. The United States Railroad Administration specified the USRA Light Mikado design for builders numbers 60933 through 60938 delivered in 1919. These six locomotives numbered 621 through 626 were designated sub-class S-1. The final six locomotives (builders numbers 65548–65553) delivered in 1924 returned to the original design with the addition of a booster engine which raised locomotive weight to . Booster engines raised tractive effort to and were subsequently added to engines 605, 606, 609, 611, 615, 616, and 626.

Replacement

Class A 2-10-2s were numbered 651 through 658. When the Maine Central began purchasing diesel locomotives, EMD F3s were numbered in the 600 series reserved for main line freight locomotives.

References

{{Maine Central Steam locomotives of the United States 2-8-2 locomotives ALCO locomotives S 2-8-0 Railway locomotives introduced in 1914 Scrapped locomotives Freight locomotives Standard gauge locomotives of the United States