In 1943, 15 more Northerns (road numbers 2201 through 2215) were delivered from the Baldwin Locomotive Works. These "war babies" were duplicates of the 1938 D&RGW 4-8-4s and had 73" drivers, 26 x 30 cylinders, a boiler pressure of 285 psi, a weight of 496,000 lbs and a tractive effort of 67,200 pounds.
There are no survivors.
|Qty.||Road Numbers||Year Built||Builder|
Rebuilt 2-8-4s (Locobase 1371) that became very successful freight engines whose tall drivers turned on roller bearings. Feed water heater was the Worthington 4 1/4 BL-2. The firebox heating surface area includes the combustion chamber, 113 sq ft (10.5 sq m) in two thermic syphons (one in the combustion chamber, one in the firebox proper), and 15 sq ft (1.4 sq m) of arch tubes.
See http://www.steamlocomotive.com/northern/mp.html (visited 7 Jan 2003), where Wes Barris says they had cast-steel beds and roller bearings.
Firebox heating surface included 136 sq ft (12.6 sq m) of thermic syphons installed in the firebox itself and the combustion chamber. These freight engines were based on the Denver and Rio Grande Western's 1800-class 4-8-4s, with a little Northern Pacific A-5 blended in. Compared to the 2100-class rebuilds (Locobase 1371) of 1940-1942, these Northerns had smaller drivers and less cylinder volume, but a higher boiler pressure setting. Their axles turned on Timken roller bearings and, like the 2100s, 14" (356 mm) piston valves supplied the cylinders. Feed water was heated by a Worthington 6 - 5A.
The last of the class was scrapped in 1956.
Another 4-8-4 class on the MP's roster were the 2101-2125, which were rebuilds from 63-in DD 2-8-4 Berkshires to 75-in driver 4-8-4s. (See Locobase 1372).
|Specifications by Steve Llanso of Sweat House Media|
|Class||2101/N-75 Victory Locomotives||N-73|
|Railroad||Missouri Pacific (MP)||Missouri Pacific (MP)|
|Number in Class||25||15|
|Locomotive Length and Weight|
|Ratio of driving wheelbase to overall engine wheebase||0.43||0.41|
|Overall Wheelbase (engine & tender)||89.81'||93.48'|
|Axle Loading (Maximum Weight per Axle)|
|Weight on Drivers||279300 lbs||279400 lbs|
|Engine Weight||445950 lbs||489000 lbs|
|Tender Light Weight||287700 lbs|
|Total Engine and Tender Weight||776700 lbs|
|Tender Water Capacity||17250 gals||19350 gals|
|Tender Fuel Capacity (oil/coal)||20 tons||20 tons|
|Minimum weight of rail (calculated)||116 lb/yard||116 lb/yard|
|Geometry Relating to Tractive Effort|
|Boiler Pressure||250 psi||285 psi|
|Cylinders (dia x stroke)||28" x 30"||26" x 30"|
|Tractive Effort||66640 lbs||67299 lbs|
|Factor of Adhesion (Weight on Drivers/Tractive Effort)||4.19||4.15|
|Firebox Area||484 sq. ft||559 sq. ft|
|Grate Area||88.30 sq. ft||106 sq. ft|
|Evaporative Heating Surface||4839 sq. ft||5306 sq. ft|
|Superheating Surface||1938 sq. ft||2200 sq. ft|
|Combined Heating Surface||6777 sq. ft||7506 sq. ft|
|Evaporative Heating Surface/Cylinder Volume||226.33||287.82|
|Computations Relating to Power Output (More Information)|
|Robert LeMassena's Power Computation||22075||30210|
|Same as above plus superheater percentage||28477||38971|
|Same as above but substitute firebox area for grate area||156090||205516|