Alaska Railroad 0-4-2 Locomotives of the USA

Class Details by Steve Llanso of Sweat House Media

Class A1 (Locobase 14135)

Data from (visited 12 May 2012) Works number was 47317 in July 1910.

The Alaska rails site gives the working pressure as 165 psi and the tractive effort as 15,350 lb (6,962 kg), which required a working pressure of 185 psi to achieve. The boiler's principal water supply lay as a saddle over the boiler (thus, a saddle tanker), but the engine also trailed a tender

Specifications by Steve Llanso of Sweat House Media
Locobase ID14,135
RailroadAlaska Railroad
Number in Class1
Road Numbers1
Number Built1
Valve Gearlink
Locomotive Length and Weight
Driver Wheelbase (ft)7
Engine Wheelbase (ft)14.92
Ratio of driving wheelbase to overall engine wheebase 0.47
Overall Wheelbase (engine & tender) (ft)14.92
Axle Loading (Maximum Weight per Axle) (lbs)37,000
Weight on Drivers (lbs)71,000
Engine Weight (lbs)82,000
Tender Loaded Weight (lbs)
Total Engine and Tender Weight (lbs)82,000
Tender Water Capacity (gals)1700
Tender Fuel Capacity (oil/coal) (gals/tons)
Minimum weight of rail (calculated) (lb/yd)59
Geometry Relating to Tractive Effort
Driver Diameter (in)44
Boiler Pressure (psi)165
High Pressure Cylinders (dia x stroke) (in)14" x 22"
Tractive Effort (lbs)13,745
Factor of Adhesion (Weight on Drivers/Tractive Effort) 5.17
Heating Ability
Firebox Area (sq ft)
Grate Area (sq ft)
Evaporative Heating Surface (sq ft)650
Superheating Surface (sq ft)
Combined Heating Surface (sq ft)650
Evaporative Heating Surface/Cylinder Volume165.83
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation
Same as above plus superheater percentage
Same as above but substitute firebox area for grate area
Power L1
Power MT


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