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 7090)

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

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 - superheated (Locobase 7089)

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

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.

Specifications by Steve Llanso of Sweat House Media
ClassI1-44I1-44 - superheated
Locobase ID7090 7089
RailroadNashville, Chattanooga & St. Louis (NC&StL)Nashville, Chattanooga & St. Louis (NC&StL)
CountryUSAUSA
Whyte4-8-04-8-0
Number in Class31
Road Numbers850-852850
GaugeStdStd
Number Built3
BuilderSchenectadyNC&StL
Year1897
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)108,000108,000
Total Engine and Tender Weight (lbs)301,000301,000
Tender Water Capacity (gals)50005000
Tender Fuel Capacity (oil/coal) (gals/tons)1010
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)208.50232.50
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 area35,44544,268
Power L140946600
Power MT234.43377.93


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