Bristol & Exeter 4-2-4 Locomotives in Great_Britain

Class Details by Steve Llanso of Sweat House Media

Class Pearson (Locobase 2544)

The B&E broke off from the Great Western in 1849. When it came time to order express engines for the "Flying Dutchman," then the fastest service in the world, the B&E's locomotive superintendent ordered these unparalleled engines. They had the tallest drivers ever in regular service on a steam engine; moreover, they were flangeless.

Remarkably for such an unusual arrangement (unique as far as Locobase knows), these engines gave very good service. Hollingsworth (1982) notes that when they were rebuilt 14 years after service entry, the original plans for these "9-footers" were sufficient. Beginning in 1876, however, the Great Western rebuilt these locomotives as 4-2-2s.

Principal Dimensions by Steve Llanso of Sweat House Media

Locobase ID2544
RailroadBristol & Exeter
CountryGreat Britain
Number in Class8
Road Numbers39-46 / 2001-2004
Number Built8
BuilderRothwell & Bolton
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)30.75 / 9.37
Axle Loading (Maximum Weight per Axle) (lbs / kg)41,500 / 18,824
Weight on Drivers (lbs / kg)41,500 / 18,824
Engine Weight (lbs / kg)112,000 / 50,802
Tender Loaded Weight (lbs / kg)
Total Engine and Tender Weight (lbs / kg)
Tender Water Capacity (gals / ML)1720 / 6.52
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) 2.20 / 2
Minimum weight of rail (calculated) (lb/yd / kg/m)69 / 34.50
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)106 / 2692
Boiler Pressure (psi / kPa)120 / 8.30
High Pressure Cylinders (dia x stroke) (in / mm)18" x 24" / 457x610
Tractive Effort (lbs / kg)7483 / 3394.24
Factor of Adhesion (Weight on Drivers/Tractive Effort) 5.55
Heating Ability
Tubes (number - dia) (in / mm)180 - 1.313" / 33
Flues (number - dia) (in / mm)
Flue/Tube length (ft / m)11 / 3.35
Firebox Area (sq ft / m2)146 / 13.57
Grate Area (sq ft / m2)23.10 / 2.15
Evaporative Heating Surface (sq ft / m2)1235 / 114.78
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)1235 / 114.78
Evaporative Heating Surface/Cylinder Volume174.72
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation2772
Same as above plus superheater percentage2772
Same as above but substitute firebox area for grate area17,520
Power L15893
Power MT313.06

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