Usambarabahn 2-8-0 Locomotives in German_East_Africa

Class Details by Steve Llanso of Sweat House Media

Class 15 (Locobase 20092)

Data from W E Robinson, Dr. K O Bertling, and O Eckenstein (translators), "Orenstein & Koppel-Arthur Koppel, Limited.", Modern Railway Practice: A Treatise on the Modern Methods of the Construction and Working of German Railways, Volume 1 (London: Reimar Hobbing, 1914), p.12. See also Roel Ramaer, The German period of East Africa, 1890-1918 in Gari la Moshi: Steam Locomotives of the East African Railways, reviewed at [], last accessed 13 August 2013.

Ramaer's description of this private line in what is present-day Tanzania notes that it was capitalized in 1893 with two million marks. The small amount meant that the line was lightly laid with rails weighing only 15 kg/m (31 lb/yard) allowing only a low axle load and including a 1 in 40 (2 1/2%) ruling grade. "Not really the distinguishing points of a substantial railway," Ramaer comments.

He continues by focusing on a particular shortcoming of a dietary nature: "[T]he wooden sleepers started almost at once to give trouble. Leached by sun and rain, and savoured as delicacies by East African termites, they were shipped to Germany to be pressure-creosoted. The only result was that the termites now felt they got real sandwiches instead of dry bread and reacted accordingly." The solution:"Only a change to steel sleepers solved the problem satisfactorily."

The O&K engine was suited for more substantial underpinnings and was delivered considerably later. Its rated speed was 45 kph (28 mph). To negotiate tight 70-m curves, two of the axles used the Golsdorf system to allow lateral play.

Principal Dimensions by Steve Llanso of Sweat House Media

Locobase ID20092
CountryGerman East Africa
Number in Class4
Road Numbers15
Number Built4
BuilderOrenstein & Koppel
Valve GearWalschaert
Locomotive Length and Weight
Driver Wheelbase (ft / m)
Engine Wheelbase (ft / m)17.72 / 5.40
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)71,650 / 32,500
Tender Loaded Weight (lbs / kg)58,202 / 26,400
Total Engine and Tender Weight (lbs / kg)129,852 / 58,900
Tender Water Capacity (gals / ML)3168 / 12
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) 7.70 / 7
Minimum weight of rail (calculated) (lb/yd / kg/m)
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)39.40 / 1000
Boiler Pressure (psi / kPa)174 / 12
High Pressure Cylinders (dia x stroke) (in / mm)14.57" x 19.69" / 370x500
Tractive Effort (lbs / kg)15,690 / 7116.87
Factor of Adhesion (Weight on Drivers/Tractive Effort)
Heating Ability
Tubes (number - dia) (in / mm)
Flues (number - dia) (in / mm)
Flue/Tube length (ft / m)
Firebox Area (sq ft / m2)
Grate Area (sq ft / m2)19.59 / 1.82
Evaporative Heating Surface (sq ft / m2)900 / 83.60
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)900 / 83.60
Evaporative Heating Surface/Cylinder Volume236.87
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation3409
Same as above plus superheater percentage3409
Same as above but substitute firebox area for grate area
Power L1
Power MT

All material Copyright ©
Wes Barris