Avignon & Marseille 4-2-0 Locomotives in France

Class Details by Steve Llanso of Sweat House Media

Class La Tarasque (Locobase 620)

Long-boilered type with outside cylinders between the leading axles and a "gothic" domed firebox. One wonders if the ride might have been improved by so large a gap between the 2 leading, and unpowered, axles. Based on Gooch's experience with Stephenson's Great A, Locobase is skeptical; see entry 3030.

Principal Dimensions by Steve Llanso of Middle Run Media

ClassLa Tarasque
Locobase ID620
RailroadAvignon & Marseille
Number in Class
Road Numbers210 / 192
Number Built
BuilderLe Benet
Valve Gear
Locomotive Length and Weight
Driver Wheelbase (ft / m)
Engine Wheelbase (ft / m)13.29 / 4.05
Ratio of driving wheelbase to overall engine wheelbase
Overall Wheelbase (engine & tender) (ft / m)
Axle Loading (Maximum Weight per Axle) (lbs / kg)26,455 / 12,000
Weight on Drivers (lbs / kg)26,455 / 12,000
Engine Weight (lbs / kg)59,547 / 27,010
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)44 / 22
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)65 / 1650
Boiler Pressure (psi / kPa)116 / 8
High Pressure Cylinders (dia x stroke) (in / mm)14.96" x 22.05" / 380x560
Tractive Effort (lbs / kg)7486 / 3395.60
Factor of Adhesion (Weight on Drivers/Tractive Effort) 3.53
Heating Ability
Tubes (number - dia) (in / mm)
Flues (number - dia) (in / mm)
Flue/Tube length (ft / m)12.57 / 3.83
Firebox Area (sq ft / m2)50.27 / 4.67
Grate Area (sq ft / m2)
Evaporative Heating Surface (sq ft / m2)513 / 47.64
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)513 / 47.64
Evaporative Heating Surface/Cylinder Volume114.36
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 area5831
Power L12141
Power MT178.42

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