Data from "Recent Locomotives of the Illinois Central Railroad," Railway Age, Volume 33, No. 23 (6 June 1902), pp. 860-862; "Prairie Type Passenger Locomotive", American Engineer and Railroad Journal, Volume 76, No 6 (June 1902), p. 199; and "Two Large Rogers Locomotives", Railway and Locomotive Engineering, Volume XV [15], No. 6 (June 1902), pp. 235, 261, and 264 . (Thanks to Chris Hohl for his 30 June 2021 email correcting the valve gear.) Works number was 5737 in April 1902.
John S Ingles (in Drury (1993)) tells us that this locomotive was procured to be compared against a single Atlantic delivered by Baldwin in the same year. After a year of trials, the Atlantic layout won and Rogers produced the batch.
RA's report conceded that the Prairies offered greater adhesive weight, as was "to be expected." "However," the report continued, " the advantage ...is somewhat offset by a larger number of driving whels and the dependent parts, with a probable increase in cost of repairs. Moreover, the first cost for this reason is greater."
Another weakness of the Prairie arrangement was its unsteadiness. RA noted the introduction of three-point suspension hangers for the trailing truck and AERJ described the pair of yokes for each axle box saying that "from these yokes the load is applied to the boxes through initial stability links or 'three-point' hangers. RA commented that "It is believed that this manner of connecting the box to the equalizers will overcome much of the side motion and contribute to the steady riding of the engine."
This single Prairie was converted into a 4-6-2 in July 1907 and took the number of the experimental Atlantic.
| Principal Dimensions by Steve Llanso of Middle Run Media | |
|---|---|
| Class | 1001 |
| Locobase ID | 5327 |
| Railroad | Illinois Central (IC) |
| Country | USA |
| Whyte | 2-6-2 |
| Number in Class | 1 |
| Road Numbers | 1001 |
| Gauge | Std |
| Number Built | 1 |
| Builder | Rogers |
| Year | 1902 |
| Valve Gear | Stephenson |
| Locomotive Length and Weight | |
| Driver Wheelbase (ft / m) | 13.50 / 4.11 |
| Engine Wheelbase (ft / m) | 30.75 / 9.37 |
| Ratio of driving wheelbase to overall engine wheelbase | 0.44 |
| Overall Wheelbase (engine & tender) (ft / m) | 62.12 / 18.93 |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | |
| Weight on Drivers (lbs / kg) | 140,200 / 63,594 |
| Engine Weight (lbs / kg) | 210,800 / 95,617 |
| Tender Loaded Weight (lbs / kg) | 147,600 / 66,950 |
| Total Engine and Tender Weight (lbs / kg) | 358,400 / 162,567 |
| Tender Water Capacity (gals / ML) | 7000 / 26.52 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 15 / 14 |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | 78 / 39 |
| Geometry Relating to Tractive Effort | |
| Driver Diameter (in / mm) | 75 / 1905 |
| Boiler Pressure (psi / kPa) | 200 / 1380 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 20" x 28" / 508x711 |
| Tractive Effort (lbs / kg) | 25,387 / 11515.36 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 5.52 |
| Heating Ability | |
| Tubes (number - dia) (in / mm) | 335 - 2" / 51 |
| Flues (number - dia) (in / mm) | |
| Flue/Tube length (ft / m) | 19 / 5.79 |
| Firebox Area (sq ft / m2) | 201.20 / 18.68 |
| Grate Area (sq ft / m2) | 51.08 / 4.74 |
| Evaporative Heating Surface (sq ft / m2) | 3535 / 328.44 |
| Superheating Surface (sq ft / m2) | |
| Combined Heating Surface (sq ft / m2) | 3535 / 328.44 |
| Evaporative Heating Surface/Cylinder Volume | 347.25 |
| Computations Relating to Power Output (More Information) | |
| Robert LeMassena's Power Computation | 10,216 |
| Same as above plus superheater percentage | 10,216 |
| Same as above but substitute firebox area for grate area | 40,240 |
| Power L1 | 11,152 |
| Power MT | 526.09 |