This pair of Americans was suited to the WM's mountainous profiles and served the line for 30 years before being scrapped in 1935 (52) and 1936 (51).
| Principal Dimensions by Steve Llanso of Sweat House Media | |
|---|---|
| Class | D-8 |
| Locobase ID | 10,788 |
| Railroad | Western Maryland (WM) |
| Country | USA |
| Whyte | 4-4-0 |
| Number in Class | 2 |
| Road Numbers | 93-94 / 51-52 |
| Gauge | Std |
| Number Built | 2 |
| Builder | Burnham, Williams & Co |
| Year | 1902 |
| Valve Gear | Stephenson |
| Locomotive Length and Weight | |
| Driver Wheelbase (ft / m) | 7.50 / 2.29 |
| Engine Wheelbase (ft / m) | 21.58 / 6.58 |
| Ratio of driving wheelbase to overall engine wheebase | 0.35 |
| Overall Wheelbase (engine & tender) (ft / m) | 45.75 / 13.94 |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | |
| Weight on Drivers (lbs / kg) | 67,165 / 30,466 |
| Engine Weight (lbs / kg) | 104,785 / 47,530 |
| Tender Loaded Weight (lbs / kg) | 65,215 / 29,581 |
| Total Engine and Tender Weight (lbs / kg) | 170,000 / 77,111 |
| Tender Water Capacity (gals / ML) | 3300 / 12.50 |
| Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT) | |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | 56 / 28 |
| Geometry Relating to Tractive Effort | |
| Driver Diameter (in / mm) | 62 / 1575 |
| Boiler Pressure (psi / kPa) | 180 / 12.40 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 18" x 24" / 457x610 |
| Tractive Effort (lbs / kg) | 19,189 / 8703.99 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 3.50 |
| Heating Ability | |
| Firebox Area (sq ft / m2) | 125 / 11.62 |
| Grate Area (sq ft / m2) | 29.24 / 2.72 |
| Evaporative Heating Surface (sq ft / m2) | 1606 / 149.26 |
| Superheating Surface (sq ft / m2) | |
| Combined Heating Surface (sq ft / m2) | 1606 / 149.26 |
| Evaporative Heating Surface/Cylinder Volume | 227.20 |
| Computations Relating to Power Output (More Information) | |
| Robert LeMassena's Power Computation | 5263 |
| Same as above plus superheater percentage | 5263 |
| Same as above but substitute firebox area for grate area | 22,500 |
| Power L1 | 5871 |
| Power MT | 385.42 |