Pacific & Eastern 2-6-2 "Prairie" Locomotives of the USA

Class Details by Steve Llanso of Sweat House Media

Class 102 / K-1a (Locobase 13690)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University, Volume 35, p. 325. See also the history of the PS & WH at, last accessed 7 January 2012. Works numbers were 34918 in July 1910.

This Pacific & Eastern road was NOT the better-known P&E headquartered in Medford, Ore, but an 8-mile (12.9-km) logging road based in Raymond, Wash and operating from 1907-1913. Soon after it took delivery of this logging Prairie, the P&E was reorganized as the Puget Sound & Willapa Harbor Railway. It ultimately reached from the Raymond tidal flats on the Willapa Harbor eastward through Chehalis and Centralia to the Milwaukee Road's junction at Maytown.

For some reason, the PS&WH renumbered the 102 as 5100, which the Milwaukee Road retained when it took over the line in December 1920. Seven years later, the Milwaukee sold the 5100 to Cascade Timber of Kangley, Wash. In 1939, the CT's line was abandoned and the 5100 passed on to Pacific States Lumber Company

Specifications by Steve Llanso of Sweat House Media
Class102 / K-1a
Locobase ID13690
RailroadPacific & Eastern
Number in Class1
Road Numbers102 / 5100
Number Built1
Valve GearStephenson
Locomotive Length and Weight
Driver Wheelbase10.50'
Engine Wheelbase26.58'
Ratio of driving wheelbase to overall engine wheebase 0.40
Overall Wheelbase (engine & tender)
Axle Loading (Maximum Weight per Axle)
Weight on Drivers98000 lbs
Engine Weight134000 lbs
Tender Light Weight70000 lbs
Total Engine and Tender Weight204000 lbs
Tender Water Capacity3500 gals
Tender Fuel Capacity (oil/coal)
Minimum weight of rail (calculated)54 lb/yard
Geometry Relating to Tractive Effort
Driver Diameter44"
Boiler Pressure180 psi
Cylinders (dia x stroke)17" x 24"
Tractive Effort24118 lbs
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.06
Heating Ability
Firebox Area128.60 sq. ft
Grate Area15.80 sq. ft
Evaporative Heating Surface2401 sq. ft
Superheating Surface
Combined Heating Surface2401 sq. ft
Evaporative Heating Surface/Cylinder Volume380.81
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation2844
Same as above plus superheater percentage2844
Same as above but substitute firebox area for grate area23148
Power L16373
Power MT430.10

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