Data from DeGolyer, Volume 72, pp. 225+. See also Malcolm Wright, "A Record-Breaking Locomotive in the Argentine Republic", Baldwin Magazine, Volume 7, No 4 (April 1929), pp.3-8Works number was 57539 in November 1923.
Painted in glowing Royal Blue and trimmed in aluminum, this single oil-burning Mountain was the four-axle stablemate of the metre-gauge Presidential Pacific described in Locobase 3713. Its glossy appearance extended even to having the outside faces of each wheel polished.
Fueled by oil from the Commodoro Rivadavia fields, the 1 offered big dimensions and power. Its Belpaire firebox's heating surface area was supplemented by 72 sq ft (6.7 sq m) in the combustion chamber and the engine used a Worthington Combined feed water heater and pump. Its piston valves measured a modest 12" (306 mm) in diameter.
Wright's report on the "Big Bus", as the engine had come to be known, noted that the Pacific Railway was up to the challenge of handling the 1. Its main line covered 1,063 km (660 miles) and was laid practically its entire distance with 100 lb/yard (50 kg/metre) rail. Upon its arrival on the property, the railway began testing it on short runs, "always with conspicuous success." For example it handled the steady 0.6% uphill grade for 60 miles (97 km) between Justo Daract and La Paz easily and its performance over the 170 mile (274 km) of the division "was a revelation to those in charge of the tests."
Over the run of tests, while hauling loads of 300-1,000 tons and over short (156 km/97 miles) distances and long (1,219 km/757 miles). the 1's coal consumption averaged between 11.5 and 14.6 kg/km (41 lb/mile to 52 lb/mile). On two International express trips, water consumption averaged between 111.7 and 146.7 litres/km (47.5- 62.5 US gallons/mile).
| Principal Dimensions by Steve Llanso of Middle Run Media | |
|---|---|
| Class | 1 |
| Locobase ID | 15279 |
| Railroad | Argentine State |
| Country | Argentina |
| Whyte | 4-8-2 |
| Number in Class | 1 |
| Road Numbers | 1 |
| Gauge | 5'6" |
| Number Built | 1 |
| Builder | Baldwin |
| Year | 1923 |
| Valve Gear | Walschaert |
| Locomotive Length and Weight | |
| Driver Wheelbase (ft / m) | 18 / 5.49 |
| Engine Wheelbase (ft / m) | 37.67 / 11.48 |
| Ratio of driving wheelbase to overall engine wheelbase | 0.48 |
| Overall Wheelbase (engine & tender) (ft / m) | 68.29 / 20.81 |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | 39,683 / 18,000 |
| Weight on Drivers (lbs / kg) | 154,000 / 69,853 |
| Engine Weight (lbs / kg) | 243,400 / 110,405 |
| Tender Loaded Weight (lbs / kg) | 149,500 / 67,812 |
| Total Engine and Tender Weight (lbs / kg) | 392,900 / 178,217 |
| Tender Water Capacity (gals / ML) | 7000 / 26.52 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 3200 / 12,112 |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | 64 / 32 |
| Geometry Relating to Tractive Effort | |
| Driver Diameter (in / mm) | 69 / 1753 |
| Boiler Pressure (psi / kPa) | 200 / 1380 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 24" x 28" / 610x711 |
| Tractive Effort (lbs / kg) | 39,736 / 18023.97 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 3.88 |
| Heating Ability | |
| Tubes (number - dia) (in / mm) | 155 - 2.25" / 57 |
| Flues (number - dia) (in / mm) | 30 - 5.5" / 140 |
| Flue/Tube length (ft / m) | 21 / 6.40 |
| Firebox Area (sq ft / m2) | 246 / 22.86 |
| Grate Area (sq ft / m2) | 52.30 / 4.86 |
| Evaporative Heating Surface (sq ft / m2) | 3060 / 284.39 |
| Superheating Surface (sq ft / m2) | 735 / 68.31 |
| Combined Heating Surface (sq ft / m2) | 3795 / 352.70 |
| Evaporative Heating Surface/Cylinder Volume | 208.72 |
| Computations Relating to Power Output (More Information) | |
| Robert LeMassena's Power Computation | 10,460 |
| Same as above plus superheater percentage | 12,447 |
| Same as above but substitute firebox area for grate area | 58,548 |
| Power L1 | 17,108 |
| Power MT | 979.65 |