Ouachita & Northwestern 2-6-2 "Prairie" Locomotives of the USA


Class Details by Steve Llanso of Sweat House Media

Class 3 (Locobase 11536)

Data from Baldwin Locomotive Works Specification for Engines, 1903, as digitized by the DeGolyer Library of Southern Methodist University Volume 25, p. 288. Works number was 22483 in November 1903.

Identical to the Prairies used by Lousiana LongLeaf Lumber on its Victoria, Fisher & Western logging road, this little 2-6-2 served the Louisiana Central's railroad nearby. The O & N in 1903 consisted of 14 miles of track running south-easterly from Clarks, La. According to the TapLines Cases heard before the Interstate Commerce Commission in 1911-1912, the O & N was never a common carrier and behaved rather rudely. Once the adjacent timber was cut and harvested, the LCL simply pulled up the tracks, leaving other users of the line in the lurch.


Class 4 (Locobase 12943)

Data from Baldwin Locomotive Works Specification for Engines, 1903, as digitized by the DeGolyer Library of Southern Methodist University Volume 25, p. 288. Works number was 22483 in November 1903.

As Baldwin-built standard-gauge logging Prairies went, this engine sat in the middle of the pack in terms of weight, heating surfaces, and power. The railroad was operated by the Louisiana Central Lumber Company.


Class 8 (Locobase 13883)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University, Volume 40, p. 34. Works number was 37580 in March 1912.

The O & N was owned by the Louisiana Central Lumber Company, which Locobase 11536 tells us was not really a common carrier. So when the timber holdings in which the #8 worked were cut over, the locomotive simply moved to other stands. A logging Prairie of a common type, the 8

Specifications by Steve Llanso of Sweat House Media
Class348
Locobase ID11536 12943 13883
RailroadOuachita & NorthwesternOuachita & NorthwesternOuachita & Northwestern
CountryUSAUSAUSA
Whyte2-6-22-6-22-6-2
Number in Class111
Road Numbers348
GaugeStdStdStd
Number Built111
BuilderBurnham, Williams & CoBurnham, Williams & CoBaldwin
Year190319061912
Valve GearStephensonStephensonStephenson
Locomotive Length and Weight
Driver Wheelbase 9.17'10' 9.17'
Engine Wheelbase23.25'25.25'23.75'
Ratio of driving wheelbase to overall engine wheebase 0.39 0.40 0.39
Overall Wheelbase (engine & tender)45.44'
Axle Loading (Maximum Weight per Axle)
Weight on Drivers60000 lbs72000 lbs63000 lbs
Engine Weight81000 lbs95000 lbs85000 lbs
Tender Light Weight54000 lbs50000 lbs60000 lbs
Total Engine and Tender Weight135000 lbs145000 lbs145000 lbs
Tender Water Capacity2500 gals2500 gals3000 gals
Tender Fuel Capacity (oil/coal)6 tons
Minimum weight of rail (calculated)33 lb/yard40 lb/yard35 lb/yard
Geometry Relating to Tractive Effort
Driver Diameter41"44"44"
Boiler Pressure180 psi170 psi180 psi
Cylinders (dia x stroke)14.5" x 20"16" x 22"15" x 20"
Tractive Effort15692 lbs18496 lbs15648 lbs
Factor of Adhesion (Weight on Drivers/Tractive Effort) 3.82 3.89 4.03
Heating Ability
Firebox Area74.90 sq. ft93.40 sq. ft83 sq. ft
Grate Area12.50 sq. ft14.40 sq. ft14.10 sq. ft
Evaporative Heating Surface924 sq. ft1348 sq. ft991 sq. ft
Superheating Surface
Combined Heating Surface924 sq. ft1348 sq. ft991 sq. ft
Evaporative Heating Surface/Cylinder Volume241.73263.30242.26
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation225024482538
Same as above plus superheater percentage225024482538
Same as above but substitute firebox area for grate area134821587814940
Power L1417844204537
Power MT460.55406.02476.30


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