C.F.Madgascar Beyer-Garratt Locomotives in Madagascar

Class Details by Steve Llanso of Sweat House Media

Class 50.801 (Locobase 699)

Data from Wiener (1930); A[rthur] E[dward] Durrant, Garratt Locomotives of the World (revised edition) (Newton Abbott, UK: David & Charles, 1981), pp 110-112; and Gavin Hamilton's compilation of Garratt data posted at [] (6 September 2005) has slightly different value -- 258 sq ft -- for the superheater. Note the unusual diameter for the flues given in Wiener. Works numbers were 2031-2032 in 1926.

Fuel in these Double Mogul Garratts was 353 cu ft of wood. Durrant noted this pair was the lasrgest and most powerful locomotives to run on Madagascar. Although laid out like most Garratts on plate frames with four simple-expansion cylinders and Belpaire fireboxes, the dssign offered some variations. The builder placed the steam pipe outside on the boiler to feed the superheater, then led the hotter steam output to the cylinders through outside pipes on the smokebox. Its wood fuel required a broad diamont staick that, Durrant wrote, made these engines :one of the few Garratt classes to sport such a 'Wild West" appurtenance."

Delivered as 101-102, reclassed later.

Principal Dimensions by Steve Llanso of Sweat House Media

Locobase ID699
Number in Class2
Road Numbers101-102
Number Built2
BuilderSA Saint Leonard
Valve GearWalschaert
Locomotive Length and Weight
Driver Wheelbase (ft / m) 7.85 / 2.39
Engine Wheelbase (ft / m)48.40 / 14.75
Ratio of driving wheelbase to overall engine wheelbase 0.16
Overall Wheelbase (engine & tender) (ft / m)53.80 / 16.40
Axle Loading (Maximum Weight per Axle) (lbs / kg)21,504 / 9754
Weight on Drivers (lbs / kg)127,792 / 57,966
Engine Weight (lbs / kg)158,704 / 71,987
Tender Loaded Weight (lbs / kg)
Total Engine and Tender Weight (lbs / kg)158,704 / 71,987
Tender Water Capacity (gals / ML)1320 / 5
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT)353 / 1336
Minimum weight of rail (calculated) (lb/yd / kg/m)35 / 17.50
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)39.80 / 1011
Boiler Pressure (psi / kPa)170 / 11.70
High Pressure Cylinders (dia x stroke) (in / mm)14.19" x 19.7" / 360x500 (4)
Tractive Effort (lbs / kg)28,804 / 13065.29
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.44
Heating Ability
Tubes (number - dia) (in / mm)191 - 1.75" / 44
Flues (number - dia) (in / mm)24 - 4.75" / 121
Flue/Tube length (ft / m)
Firebox Area (sq ft / m2)114.50 / 10.64
Grate Area (sq ft / m2)22.40 / 2.08
Evaporative Heating Surface (sq ft / m2)1203 / 111.80
Superheating Surface (sq ft / m2)248 / 23.05
Combined Heating Surface (sq ft / m2)1451 / 134.85
Evaporative Heating Surface/Cylinder Volume166.81
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation3808
Same as above plus superheater percentage4455
Same as above but substitute firebox area for grate area22,774
Power L16266
Power MT648.59

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