Norfolk & Western 4-4-2 "Atlantic" Locomotives of the USA

Class Details by Steve Llanso of Sweat House Media

Class J (Locobase 4093)

Taken from a table in Paul T Warner's article on Atlantics in the Railway & Locomotive Historical Society Bulletin #62 (1943, p 20), with additional information from

Angus Sinclair (ed), Railway and Locomotive Engineering, March 1903, p. 134; N&W 12 - 1929 supplied in May 2005 by Allen Stanley from his extensive Raildata collection; and DeGolyer, Volumes 25, p. 140 and 26, p. 270. (Thanks to Chris Hohl for his 10 December 2016 email pointing out the updated valve gear.) Works numbers were 22178, 22180, 22254, 22292 in May 1903; 22309, 22367 in June; and 23922 in March 1904.

This was a relatively small Atlantic designed by Superintendent of Motive Power W H Lewis that was delivered to the N&W in small numbers. Equalization was continuous along all five axles; adhesion weight could be adjusted by shifting the position of a spring that bore a casting that spanned the frame under the firebox.

The engines were delivered with 9 1/2" (241 mm) piston valves. Chris Hohl noticed in a 1917 photograph that the N&W replaced the original inside valve gear with the outside radial Baker-Pilliod gear. By that time weight on the drivers came to 85,390 lb (38,732 kg) while the engine's allup weight was reckoned as 167,700 lb (76,068 kg). Max axle loading weighed in at 43,370 lb (19,672 kg) and rested on the leading set of drivers.

See excerpt from article reproduced on (4 April 2004). The N&W J is used as an example of the gains made when the builder put a trailing axle under the boiler.

But for the N&W, the 4-4-2 layout was a bad fit and these were the only engines of that arrangement they bought or built. None was superheated and all had been retired by 1926.

Specifications by Steve Llanso of Sweat House Media
Locobase ID4093
RailroadNorfolk & Western (N&W)
Number in Class7
Road Numbers600-606
Number Built7
BuilderBurnham, Williams & Co
Valve GearStephenson
Locomotive Length and Weight
Driver Wheelbase (ft) 6.83
Engine Wheelbase (ft)28.71
Ratio of driving wheelbase to overall engine wheebase 0.24
Overall Wheelbase (engine & tender) (ft)53.01
Axle Loading (Maximum Weight per Axle) (lbs)
Weight on Drivers (lbs)80,930
Engine Weight (lbs)169,090
Tender Loaded Weight (lbs)100,000
Total Engine and Tender Weight (lbs)269,090
Tender Water Capacity (gals)6000
Tender Fuel Capacity (oil/coal) (gals/tons)10
Minimum weight of rail (calculated) (lb/yd)67
Geometry Relating to Tractive Effort
Driver Diameter (in)79
Boiler Pressure (psi)200
High Pressure Cylinders (dia x stroke) (in)19" x 28"
Tractive Effort (lbs)21,751
Factor of Adhesion (Weight on Drivers/Tractive Effort) 3.72
Heating Ability
Firebox Area (sq ft)162
Grate Area (sq ft)45.10
Evaporative Heating Surface (sq ft)2888
Superheating Surface (sq ft)
Combined Heating Surface (sq ft)2888
Evaporative Heating Surface/Cylinder Volume314.31
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation9020
Same as above plus superheater percentage9020
Same as above but substitute firebox area for grate area32,400
Power L110,598
Power MT577.40