Petersburg 2-2-0 "Planet" Locomotives in the USA

Class Details by Steve Llanso of Sweat House Media

Class Pioneer (Locobase 4089)

Although laid out along Stephenson multi-tube boiler lines, Railroad Gazette of 12 April 1901 comments that " the design was inferior to even earlier engines by Stephenson and Bury." The locomotive showed the D-shaped Bury firebox behind the single driving axle and inside cylinders driving the rear axle. The attribution to the Petersburg (later part of the RF&P) as owning railroad constitutes a bit of deductive reasoning by Herbert T. Walker, author of the RG article.

Principal Dimensions by Steve Llanso of Sweat House Media

Locobase ID4089
Number in Class1
Road Numbers
Number Built1
BuilderRothwell, Hick & Rothwell
Valve Gear
Locomotive Length and Weight
Driver Wheelbase (ft / m)
Engine Wheelbase (ft / m)
Ratio of driving wheelbase to overall engine wheelbase
Overall Wheelbase (engine & tender) (ft / m)
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)
Engine Weight (lbs / kg)
Tender Loaded Weight (lbs / kg)
Total Engine and Tender Weight (lbs / kg)
Tender Water Capacity (gals / ML)
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT)
Minimum weight of rail (calculated) (lb/yd / kg/m)
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)54 / 1372
Boiler Pressure (psi / kPa)40 / 2.80
High Pressure Cylinders (dia x stroke) (in / mm)9" x 18" / 229x457
Tractive Effort (lbs / kg)918 / 416.40
Factor of Adhesion (Weight on Drivers/Tractive Effort)
Heating Ability
Tubes (number - dia) (in / mm)50 - 1.75" / 44
Flues (number - dia) (in / mm)
Flue/Tube length (ft / m) 6.33 / 1.93
Firebox Area (sq ft / m2)
Grate Area (sq ft / m2)
Evaporative Heating Surface (sq ft / m2)150 / 13.94
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)150 / 13.94
Evaporative Heating Surface/Cylinder Volume112.78
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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Wes Barris