Outshopped in 1903, #1139 is one of one hundred and
three 1050 Class Prairie type (2-6-2) locomotives built for
the AT&SF by Baldwin from 1902 to 1903 (#1050-#1152). As
built, it was a four cylinder Vauclain compound with
17" x 28" high pressure and 28" x 28" low pressure cylinders. The engine had two pistons mounted in line and moving in parallel to drive a common crosshead, one on each side of the locomotive. The valve was on the inside, controlled by Stephenson valve gear.
The main advantage claimed for compounding was lower fuel and water consumption, but uneven forces and excess crosshead wear produced by Vauclains increased maintenance costs and largely offset any fuel economies. The complex valve assembly and the starter valve, which allowed admission of high pressure steam directly to the low pressure cylinder, also increased maintenance costs.
By the1900s, many US railroads were abandoning compounds and converting ones they owned to single-expansion locomotives. The AT&SF simplified all its 1050s between 1910 and 1922 with 23½" x 28" cylinders.
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At 210,190 lbs, 141,690 lbs on its drivers, #1079 weighs 20,190 lbs more than as-built. The additional weight increased tractive effort from 29,134 lbs to 38,097 lbs.
#1067's grate is 55.3 sq ft and the firebox is 195 sq ft. An oil burner with a total heating surface of 3,738 sq ft, it operated at a boiler pressure of 200 psi.
Above left, the tender weighs 112,610 lbs light with a capacity of 7,000 gallons of water and 2,350 gallons of oil. Above right, #1067's backhead.
#1139 was donated to the City of Dodge in 1945 and is on display at the Boot Hill Museum between Front Street and Wyatt Earp Blvd. The AT&SF was one of the main purchasers of 2-6-2s, buying two hundred and thirty-three between 1901 and 1903. A number have survived and several are dotted about the South-West. You can see others on the ATSF #1024, ATSF #1050, ATSF #1067, ATSF #1079, ATSF #1129, ATSF #1819 and ATSF #1880 pages of this website.