One of several narrow-gauge designs built for war service during World War I. Data from Bruce (1952) and from WJK Davies Light Railways of the First World War (NY;Reprints of Economic Classics, 1968).
Davies notes that these were the most powerful steam locomotives on the light railways. They were well-liked because of both that power and of their double-ender running. He adds that after the war, a number of these Alcos ran on French lines. One in particular was the Tramway de Pithwies a' Towy, which operated three of these obviously durable engines until it closed in 1964.
| Principal Dimensions by Steve Llanso of Middle Run Media | |
|---|---|
| Class | Trench loco |
| Locobase ID | 5043 |
| Railroad | War Department Light Railways |
| Country | Great Britain |
| Whyte | 2-6-2T |
| Number in Class | 100 |
| Road Numbers | 1207-1300 |
| Gauge | 60 cm |
| Number Built | 100 |
| Builder | Alco-Cooke |
| Year | 1917 |
| Valve Gear | Walschaert |
| Locomotive Length and Weight | |
| Driver Wheelbase (ft / m) | 5.50 / 1.68 |
| Engine Wheelbase (ft / m) | 16.50 / 5.03 |
| Ratio of driving wheelbase to overall engine wheelbase | 0.33 |
| Overall Wheelbase (engine & tender) (ft / m) | |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | 8036 / 3645 |
| Weight on Drivers (lbs / kg) | 23,772 / 10,783 |
| Engine Weight (lbs / kg) | 38,500 / 17,463 |
| Tender Loaded Weight (lbs / kg) | |
| Total Engine and Tender Weight (lbs / kg) | 38,500 / 17,463 |
| Tender Water Capacity (gals / ML) | 475 / 1.80 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | 13 / 6.50 |
| Geometry Relating to Tractive Effort | |
| Driver Diameter (in / mm) | 27 / 686 |
| Boiler Pressure (psi / kPa) | 175 / 1210 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 9" x 14" / 229x356 |
| Tractive Effort (lbs / kg) | 6248 / 2834.05 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 3.80 |
| Heating Ability | |
| Tubes (number - dia) (in / mm) | |
| Flues (number - dia) (in / mm) | |
| Flue/Tube length (ft / m) | 8.50 / 2.59 |
| Firebox Area (sq ft / m2) | |
| Grate Area (sq ft / m2) | 5.40 / 0.50 |
| Evaporative Heating Surface (sq ft / m2) | 264 / 24.54 |
| Superheating Surface (sq ft / m2) | |
| Combined Heating Surface (sq ft / m2) | 264 / 24.54 |
| Evaporative Heating Surface/Cylinder Volume | 256.10 |
| Computations Relating to Power Output (More Information) | |
| Robert LeMassena's Power Computation | 945 |
| Same as above plus superheater percentage | 945 |
| Same as above but substitute firebox area for grate area | |
| Power L1 | |
| Power MT | |