Great Northern 2-6-2 "Prairie" Type Locomotives

Class J-1 / J-2 (Locobase 5388)

Data from table in the June 1907 AERJ.These were Prairie freighters to move fast freights across relatively flat profiles. They featured a long Belpaire firebox, low drivers, and a long wheelbase. In addition to the 50 in the 1906 order (manufactured from March to August), the GN bought another 100 J-2s a year later. Baldwin produced that latter batch in February-June 1907.

Unlike Santa Fe's experience, however, the Great Northern wasn't really satisfied with the arrangement. Fifteen were converted to H-6 class 4-6-2s in 1923, the others entered retirement in the late 1930s and early 1940s.

Class J-1-S/ J-2 -S (Locobase 7492)

Data from GN 1 - 1929 Loco Diagrams supplied in May 2005 by Allen Stanley from his extensive collection.

Beginning in the 1920s, the GN took these J-2s in hand and upgraded them. They were unusually successful in substituting heating surface in the flues and in the 30 superheater elements for the lost heating surface in the 122 small tubes they deleted - the total heating surface nearly matches that of the saturated boiler. Also, the railroad increased the size of the cylinders while cutting the boiler pressure, thus losing little calculated tractive effort while stressing the boiler less.

Fifteen of these engines later made their way to the Spokane, Portland & Seattle.

Class J-3-S (Locobase 8853)

Data from GN 1916 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive collection.

Very unusual cylinder diameter on this Prairie locomotive and not characteristic of the other conversions of this class; otherwise its Belpaire-firebox lines were quite familiar. Originally designated J-3, it was redesignated J-1-S (probably when the railway decided it would be a lone engine). In July 1925, the GN sold 1549 to the Spokane, Portland & Seattle as their F-1 (466). As the F-1, the engine ran until May 1948.

Specifications
Class	J-1 / J-2	J-1-S/ J-2 -S	J-3-S
Locobase ID	5388	7492	8853
Railroad	Great Northern (GN)	Great Northern (GN)	Great Northern (GN)
Whyte	2-6-2	2-6-2	2-6-2
Road Numbers	1500-1649	1550-1649	1549
Gauge	Std	Std	Std
Builder	Burnham, Williams & Co	shops	GN
Year	1906	1913	1913
Valve Gear	Walschaert	Walschaert	Walschaert
	Locomotive Length and Weight
Driver Wheelbase	13'	13'	13'
Engine Wheelbase	30.75'	21.50'	30.75'
Ratio of driving wheelbase to overall engine wheebase	0.42	0.60	0.42
Overall Wheelbase (engine & tender)	63.67'	63.62'	63.62'
Axle Loading (Maximum Weight per Axle)	53600 lbs	53600 lbs	53000 lbs
Weight on Drivers	151000 lbs	151000 lbs	151000 lbs
Engine Weight	209000 lbs	209000 lbs	209000 lbs
Tender Light Weight	148200 lbs	152200 lbs	148200 lbs
Total Engine and Tender Weight	357200 lbs	361200 lbs	357200 lbs
Tender Water Capacity	8000 gals	8000 gals	8000 gals
Tender Fuel Capacity (oil/coal)	13 tons	15 tons	13 tons
Minimum weight per yard of rail on which locomotive could run	83.89 lb rail	83.89 lb rail	83.89 lb rail
	Geometry Relating to Tractive Effort
Driver Diameter	69"	69"	69"
Boiler Pressure	210 psi	185 psi	170 psi
Cylinders (dia x stroke)	22" x 30"	23.5" x 30"	25.75" x 30"
Tractive Effort	37563 lbs	37757 lbs	41658 lbs
Factor of Adhesion (Weight on Drivers/Tractive Effort)	4.02	4.00	3.62
	Heating Ability
Firebox Area	210 sq. ft	211 sq. ft	210.77 sq. ft
Grate Area	53.15 sq. ft	54.15 sq. ft	54.15 sq. ft
Evaporative Heating Surface	3487	2696	2718
Superheating Surface		690	470
Combined Heating Surface	3487	3386	3188
Evaporative Heating Surface/Cylinder Volume	264.19	179.01	150.31
	Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation	11161.50	10017.75	9205.50
Same as above plus superheater percentage	11161.50	12059.17	10562.65
Same as above but substitute firebox area for grate area	44100	46989.56	41113.37
Power L1	8301.24	14071.47	8651.38
Power MT	363.60	616.34	378.93