Trasandino Argentino Kitson-Meyer Locomotives in Argentina

Class Details by Steve Llanso of Sweat House Media

Class Z (Locobase 20298)

Data from "The Transandine [sic] Railway", Locomotive Magazine, Volume 16 (15 February 1910), p. 26. See also Ian Thomson, "The Transandine Railway: a Hundred Year Long Financial Disaster that Still Attracts Investors", pp. 1-8, archived at [], last accessed 21 October 2017.

See Locobase 20297 for a full description of these unusual rack & adhesion Kitson-Meyer locomotives, which were perhaps overendowed with cylinder volume when they included both a "small" rack engine forward and a larger rack engine under the rear bogie.

Ian Thomson's typically well-informed and well-written account includes the observation that "Nature has never been a friend of the Transandino." Locobase 20294 briefly outlines the 70 km on the Chilean side of the summit. In Argentina, the Transandine's 179 km (111 miles) started westward from Mendoza and for 131 km offered grades gentle enough to allow adhesion-only operation. Even the 48 km of occasional Abt rack sections sloped only at about 6% compared to the Chilean sides 8 1/2%.

Even so, Thomson describes the Chilean-Argentine Transandine as "an operating nightmare" that, when in steam, "was difficult and costly".

He reports that these Zs, while complicated, were successful, long-lived locomotives.

Principal Dimensions by Steve Llanso of Sweat House Media

Locobase ID20298
RailroadTrasandino Argentino
Number in Class6
Road Numbers40-45
Number Built6
BuilderKitson & Co
Valve GearWalschaert
Locomotive Length and Weight
Driver Wheelbase (ft / m)10.50 / 3.20
Engine Wheelbase (ft / m)31.50 / 9.60
Ratio of driving wheelbase to overall engine wheelbase 0.33
Overall Wheelbase (engine & tender) (ft / m)31.50 / 9.60
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)113,456 / 51,463
Engine Weight (lbs / kg)200,032 / 90,733
Tender Loaded Weight (lbs / kg)
Total Engine and Tender Weight (lbs / kg)200,032 / 90,733
Tender Water Capacity (gals / ML)2376 / 9
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) 2.75 / 3
Minimum weight of rail (calculated) (lb/yd / kg/m)
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)36 / 914
Boiler Pressure (psi / kPa)200 / 13.80
High Pressure Cylinders (dia x stroke) (in / mm)16.5" x 19" / 419x483 (4)
Tractive Effort (lbs / kg)48,854 / 22159.83
Factor of Adhesion (Weight on Drivers/Tractive Effort) 2.32
Heating Ability
Tubes (number - dia) (in / mm)292 - 1.875" / 48
Flues (number - dia) (in / mm)
Flue/Tube length (ft / m)12.33 / 3.76
Firebox Area (sq ft / m2)130 / 12.08
Grate Area (sq ft / m2)31 / 2.88
Evaporative Heating Surface (sq ft / m2)1898 / 176.33
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)1898 / 176.33
Evaporative Heating Surface/Cylinder Volume201.82
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation6200
Same as above plus superheater percentage6200
Same as above but substitute firebox area for grate area26,000
Power L13251
Power MT

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