| Maine Central class W | |
| Powertype: | Steam |
| Hatnote: | Reference:[1] |
| Builder: | ALCO |
| Builddate: | 1910–1914 |
| Totalproduction: | 28 |
| Whytetype: | 2-8-0 |
| Uicclass: | 1'D |
| Leadingdiameter: | 330NaN0 |
| Driverdiameter: | 630NaN0 |
| Wheelbase: | 25feet |
| Length: | 71feet including tender |
| Height: | 14feet |
| Locoweight: | 1980001NaN1 |
| Locotenderweight: | 3380001NaN1 |
| Fueltype: | Coal |
| Fuelcap: | 12 t |
| Watercap: | 70000NaN0 |
| Boilerpressure: | 185lb/in2 |
| Firearea: | 50.22NaN2 |
| Cylindercount: | Two |
| Cylindersize: | 23x |
| Valvegear: | Walschaerts |
| Tractiveeffort: | 370001NaN1 |
| Retiredate: | 1954 |
| Preservedunits: | 2 (Remainder Scrapped) |
| Disposition: | No. 501, under restoration |
Maine Central Railroad Class W locomotives were intended for heavy freight service. They were of 2-8-0 wheel arrangement in the Whyte notation, or "1'D" in UIC classification. They replaced earlier class O 4-6-0 locomotives beginning in 1910. They were in turn replaced by class S 2-8-2 locomotives for the heaviest freight service beginning in 1914, but remained in use on lighter freight trains until replaced by diesel locomotives after World War II.[1]
All were built in American Locomotive Company's plant at Schenectady, New York. The first nine built in 1910 (builders numbers 47732-47736 & 49207-49210) were 5000lb lighter than the infobox figure. Sub-class W-1 consisted of seven locomotives added in 1912 (builders numbers 50933-50939) and eight more (builders numbers 52989-52996) delivered in 1913. The last four designated sub-class W-2 (builders numbers 54564-54567) were delivered in 1914 and were 4000lb heavier than the infobox figure.[1]
Class W locomotives were numbered from 501 to 528 as delivered. Numbers 501 and 519 were officially property of the European and North American Railway (E&NA) as a condition of the lease of that company by the Maine Central Railroad. They therefore avoided scrapping until Maine Central purchased E&NA to remove the lease obligation in 1955. Two locomotives survived; No. 501 is currently under restoration to operating condition at the Conway Scenic Railroad and No. 519 was on display outside at the Steamtown National Historic Site, exposed to the elements.[2] [3]
When the Maine Central began purchasing diesel locomotives, road switchers were numbered in the 500 series previously reserved for the W class.[4] ALCO RS-2s and ALCO RS-3s were numbered 551 through 557, and EMD GP7s were numbered 561 through 569 and 571 through 581.[5]