ATSF Class 2900 Northern (4-8-4) type #2913 is displayed in Riverview Park beside the Mississippi River in Fort Madison, IA.
With over 2,200 miles of main line stretching from Chicago to California, the AT&SF needed quality motive power. Between 1927 and 1929, it bought fourteen Northerns (#3751-#3764) and eventually rostered sixty-five, all built by Baldwin.
The last thirty (#2900-#2929) delivered in
1944 were based on the 3765 class built in 1938, but wartime restrictions meant some components were made of heavier
materials. As a result, the 2900s were the heaviest Northerns ever built. They hauled freight until WWII ended and were then assigned to the Scout and Grand Canyon Limited.
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#2913 has a 108 sq ft grate. Thermic syphons of 30.5 sq ft were fitted to the 479 sq ft firebox, which included 124 sq ft in an 84" long combustion chamber. With an additional 2,366 sq ft of superheating, #2903 had a total heating surface of 7,678 sq ft.
The engine weighs 510,150 lbs and has
28" x 32" cylinders. An oil burner operating at a boiler pressure of 300 psi, it delivered 79,968 lbs tractive effort. The tender weighs 464,700 lbs light and has a capacity of 245,000 gallons of water and 7,170 gallons of oil.
Above, the 2900s were
fitted with Walschaert valve gear, lightweight roller bearing rods and 80" Boxpok drivers, except for the fourth axle, which sported a 1938 style Baldwin Disc driver.
Right, note the smoke stack lifting extension. This provided better draft and helped lift the smoke.