Nashville, Chattanooga & St Louis 4-8-0 "Mastodon" Locomotives of the USA

Class Details by Steve Llanso of Sweat House Media

Class I1-44 (Locobase 14418)

Data from NC&StL 1 - 1921 Locomotive Diagrams and Cranes supplied in May 2005 by Allen Stanley from his extensive Raildata collection.

The Butte, Anaconda & Pacific bought three cross-compound Mastodons from Schenectady in 1897; see Locobase 14417. After the BA&P's electrification was completed in 1914, the class was idled until it was sold in 1917 to the as their class I1-44; they were renumbered 850-852. In 1920, all three engines were slightly modified in a significant way when the LP cylinder was removed and a second 23" HP cylinder was fitted instead. In an effort to encourage adhesion, the altering railroad (either the BA&P or the Nashville, Chattanooga & St Louis) also reduced the boiler pressure by 40 psi (2.75 bar). Even so, a look at the data shows that these engines were still likely to be slippery.

The NC&StL operated the engines in transfer service or as heavy switchers for a decade or more. In 1924, the NC&StL installed a superheater in 850; see Locobase 14419. Two years later, the railroad retired the 852 in September 1926. The 850 followed in November 1927 and the 851 in May 1932.

Class I1-44 - superheated (Locobase 14419)

Data from NC&StL 1 - 1921 Locomotive Diagrams and Cranes supplied in May 2005 by Allen Stanley from his extensive Raildata collection.

The Dixie Line must have wondered after they converted their three adopted cross-compound Mastodons to simple expansion whether this big switcher/transfer engine trio could have extended lives if they were fitted with a modest degree of superheat. So they installed a small Schmidt-type unit in the 850 in 1924. Results must have disappointed as the 850 was scrapped November 1927, after the 852 and five years before the 851..

Specifications by Steve Llanso of Sweat House Media
ClassI1-44I1-44 - superheated
Locobase ID14,418 14,419
RailroadNashville, Chattanooga & St LouisNashville, Chattanooga & St Louis
Number in Class31
Road Numbers850-852850
Number Built
Valve GearStephensonStephenson
Locomotive Length and Weight
Driver Wheelbase (ft)15.7515.75
Engine Wheelbase (ft)26.7526.75
Ratio of driving wheelbase to overall engine wheebase 0.59 0.59
Overall Wheelbase (engine & tender) (ft)53.8353.83
Axle Loading (Maximum Weight per Axle) (lbs)
Weight on Drivers (lbs)154,000154,000
Engine Weight (lbs)193,000193,000
Tender Loaded Weight (lbs)112,000108,000
Total Engine and Tender Weight (lbs)305,000301,000
Tender Water Capacity (gals)45004500
Tender Fuel Capacity (oil/coal) (gals/tons) 9.50 9.50
Minimum weight of rail (calculated) (lb/yd)6464
Geometry Relating to Tractive Effort
Driver Diameter (in)5656
Boiler Pressure (psi)170170
High Pressure Cylinders (dia x stroke) (in)23" x 32"23" x 32"
Tractive Effort (lbs)43,68043,680
Factor of Adhesion (Weight on Drivers/Tractive Effort) 3.53 3.53
Heating Ability
Firebox Area (sq ft)206.51232.50
Grate Area (sq ft)3535
Evaporative Heating Surface (sq ft)29282358
Superheating Surface (sq ft)320
Combined Heating Surface (sq ft)29282678
Evaporative Heating Surface/Cylinder Volume190.28153.24
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation59505950
Same as above plus superheater percentage59506664
Same as above but substitute firebox area for grate area35,10744,268
Power L140846600
Power MT233.86377.93

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