Skagit 2-6-2 "Prairie" Locomotives in the USA


Class Details by Steve Llanso of Sweat House Media

Class 6 (Locobase 15489)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University, Vol 80, p. 415. See also Charles E Benjamin, "History of the Incline: Up and Down on the Incline Scene", Trolley Fare (September/October 1987), archived at the Seattle City Light website at [], last accessed 17 October 2013. Works number was 60440 in July 1928.

Proportioned like a logging engine, this oil-burning, superheated Prairie had 8" (203 mm) piston valves.

The 6 supported several Seattle City Light water projects in the Skagit River Valley that lay 140 miles (225 km) northeast of the big city. The railway used an incline, electric power in the steepest sections, a car ferry, winch, and steam power from Rockport Junction on the Great Northern to two sites: the Gorge powerhouse and the dam at Newhalem, Wash.

The 6--the Skagit's only steamer--rode on the last of the modes from 1928 to 1954 when the railroad was abandoned. Maximum curvature was a relatively high 35 degrees (radii of 135 feet), but ruling grades came to only 1.2% compensated, although there were short grades of 4%. 6 provided the railway's passenger power for both the workers on the projects and for the excursions that took tourists to sample the dramatic views.

After the Skagit closed, the 6 was preserved in Newhalem. In 1973, a short-lived excursion road built a shed in Concrete, WA to house the 6 during its restoration, but never had the funds to complete the project. As of 2013, the 6 remained on display in Newhalem.

Principal Dimensions by Steve Llanso of Sweat House Media
Class6
Locobase ID15,489
RailroadSkagit
CountryUSA
Whyte2-6-2
Number in Class1
Road Numbers6
GaugeStd
Number Built1
BuilderBaldwin
Year1928
Valve GearWalschaert
Locomotive Length and Weight
Driver Wheelbase (ft / m) 9.33 / 2.84
Engine Wheelbase (ft / m)26.75 / 8.15
Ratio of driving wheelbase to overall engine wheebase 0.35
Overall Wheelbase (engine & tender) (ft / m)48.33 / 14.73
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)105,000 / 47,627
Engine Weight (lbs / kg)134,000 / 60,781
Tender Loaded Weight (lbs / kg)75,000 / 34,019
Total Engine and Tender Weight (lbs / kg)209,000 / 94,800
Tender Water Capacity (gals / ML)3500 / 13.26
Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT)1500 / 5.70
Minimum weight of rail (calculated) (lb/yd / kg/m)58 / 29
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)44 / 1118
Boiler Pressure (psi / kPa)170 / 11.70
High Pressure Cylinders (dia x stroke) (in / mm)18" x 24" / 457x610
Tractive Effort (lbs / kg)25,537 / 11583.40
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.11
Heating Ability
Firebox Area (sq ft / m2)114 / 10.59
Grate Area (sq ft / m2)28.15 / 2.62
Evaporative Heating Surface (sq ft / m2)1706 / 158.49
Superheating Surface (sq ft / m2)378 / 35.12
Combined Heating Surface (sq ft / m2)2084 / 193.61
Evaporative Heating Surface/Cylinder Volume241.35
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation4786
Same as above plus superheater percentage5647
Same as above but substitute firebox area for grate area22,868
Power L110,014
Power MT630.77

All material Copyright © SteamLocomotive.com
Wes Barris