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


Class Details by Steve Llanso of Sweat House Media

Class I1-44 (Locobase 7090)

Data from NC&StL 1 - 1921 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

Drury (1993) makes no mention of this Twelve-wheeler trio, shown here in its earlier saturated-steam configuration. The long wheelbase and the long stroke typical of the arrangement shows in these as well. Clearly, the railroad thought enough of them to put in some flues and the result is described in Locobase 7089.

These two were scrapped in September 1926 (852) and August 1932 (851).


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 Rail Data Exchange.

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 7089)

Data from NC&StL 1 - 1921 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

Drury (1993) makes no mention of this Twelve-wheeler trio, shown here in its superheated form and in Locobase 7090 in its earlier saturated-steam configuration. When the engine was superheated, it lost some heating surface area as often happened, but gained 26 sq ft of arch tubes as part of its firebox heating surface.

Perhaps surprisingly, given the effort made to modernize the design, 850 was scrapped in November 1927, only a year after 851.


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 Rail Data Exchange.

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..

Principal Dimensions by Steve Llanso of Sweat House Media
ClassI1-44I1-44I1-44 - superheatedI1-44 - superheated
Locobase ID7090 14,418 7089 14,419
RailroadNashville, Chattanooga & St. Louis (NC&StL)Nashville, Chattanooga & St. Louis (NC&StL)Nashville, Chattanooga & St. Louis (NC&StL)Nashville, Chattanooga & St. Louis (NC&StL)
CountryUSAUSAUSAUSA
Whyte4-8-04-8-04-8-04-8-0
Number in Class3311
Road Numbers850-852850-852850850
GaugeStdStdStdStd
Number Built3
BuilderSchenectadyAlco-SchenectadyNC&StLAlco-Schenectady
Year189719201924
Valve GearStephensonStephensonStephensonStephenson
Locomotive Length and Weight
Driver Wheelbase (ft / m)15.75 / 4.8015.75 / 4.8015.75 / 4.8015.75 / 4.80
Engine Wheelbase (ft / m)26.75 / 8.1526.75 / 8.1526.75 / 8.1526.75 / 8.15
Ratio of driving wheelbase to overall engine wheebase 0.59 0.59 0.59 0.59
Overall Wheelbase (engine & tender) (ft / m)53.83 / 16.4153.83 / 16.4153.83 / 16.4153.83 / 16.41
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)154,000 / 69,853154,000 / 69,853154,000 / 69,853154,000 / 69,853
Engine Weight (lbs / kg)193,000 / 87,543193,000 / 87,543193,000 / 87,543193,000 / 87,543
Tender Loaded Weight (lbs / kg)108,000112,000 / 50,802108,000108,000 / 48,988
Total Engine and Tender Weight (lbs / kg)301,000305,000 / 138,345301,000301,000 / 136,531
Tender Water Capacity (gals / ML)5000 / 18.944500 / 17.055000 / 18.944500 / 17.05
Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT)10 / 9.10 9.50 / 8.6010 / 9.10 9.50 / 8.60
Minimum weight of rail (calculated) (lb/yd / kg/m)64 / 3264 / 3264 / 3264 / 32
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)56 / 142256 / 142256 / 142256 / 1422
Boiler Pressure (psi / kPa)170 / 11.70170 / 11.70170 / 11.70170 / 11.70
High Pressure Cylinders (dia x stroke) (in / mm)23" x 32" / 584x81323" x 32" / 584x81323" x 32" / 584x81323" x 32" / 584x813
Tractive Effort (lbs / kg)43,680 / 19812.9443,680 / 19812.9443,680 / 19812.9443,680 / 19812.94
Factor of Adhesion (Weight on Drivers/Tractive Effort) 3.53 3.53 3.53 3.53
Heating Ability
Firebox Area (sq ft / m2)208.50 / 19.38206.51 / 19.19232.50 / 21.61232.50 / 21.60
Grate Area (sq ft / m2)35 / 3.2535 / 3.2535 / 3.2535 / 3.25
Evaporative Heating Surface (sq ft / m2)2928 / 272.122928 / 272.022358 / 219.142358 / 219.06
Superheating Surface (sq ft / m2)320 / 29.74320 / 29.73
Combined Heating Surface (sq ft / m2)2928 / 272.122928 / 272.022678 / 248.882678 / 248.79
Evaporative Heating Surface/Cylinder Volume190.28190.28153.24153.24
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation5950595059505950
Same as above plus superheater percentage5950595066646664
Same as above but substitute firebox area for grate area35,44535,10744,26844,268
Power L14094408466006600
Power MT234.43233.86377.93377.93

All material Copyright © SteamLocomotive.com
Wes Barris