Nashville, Chattanooga & St. Louis 4-6-2 "Pacific" Type Locomotives

Class K-1A-37 (Locobase 5463)

Data from NC&StL 6 - 1951 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive collection.

Relatively small Pacifics for Atlanta Division main and local passenger service. When delivered, their boilers were pressed to 185 psi and they had fireboxes with direct heating surface measuring 223 sq ft, including 28 sq ft of arch tubes. A later rebuild deleted the arch tubes in favor of 65 sq ft of thermic syphons as part of firebox heating surface, which resulted in the figure shown in the specifications.

The last of these was retired in 1948.

Class K-2B-41 (Locobase 7086)

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

These were the heavyweight express engines on the Dixie Line when they entered service. Their relatively small drivers speak to the undulating profile of most of this railroad's territory. Over time, the engines were rebuilt and the result is shown in Locobase 7087.

Class K-2B-41 - upgraded (Locobase 7087)

Data from NC&StL 2 - 1947 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive collection.

Over time, the K2 engines first procured in 1912-1913 (see Locobase 7086) were rebuilt with feedwater heaters and the firebox heating surface then amounted to 328 sq ft of which 14 sq ft were arch tubes (14.8 sq ft fewer than originally installed) and 73 sq ft of thermic syphons. At the same time, boiler pressure grew to 200 psi and the cylinder diameter increased by an inch.

Two - 535-536 -- were streamlined for the Dixie Flagler (1940) and the City of Memphis. 535 later gained a cast-steel frame, Timken roller bearings on all axles and a bigger tender that held 16 tons of coal and 15,000 gallons of water. Drury (1993) says this streamliner averaged 14,000 miles/month for several years on the Memphis-Nashville run.

Specifications
Class	K-1A-37	K-2B-41	K-2B-41 - upgraded
Locobase ID	5463	7086	7087
Railroad	Nashville, Chattanooga & St. Louis	Nashville, Chattanooga & St. Louis	Nashville, Chattanooga & St. Louis
Whyte	4-6-2	4-6-2	4-6-2
Road Numbers	501-511	530-537	530-537
Gauge	Std	Std	Std
Builder	Baldwin	Baldwin	NCSL
Year	1915	1912
Valve Gear	Walschaert	Walschaert	Walschaert
	Locomotive Length and Weight
Driver Wheelbase	13'	13'	13'
Engine Wheelbase	34.08'	34.08'	35.62'
Ratio of driving wheelbase to overall engine wheebase	0.38	0.38	0.36
Overall Wheelbase (engine & tender)	69.40'	68.15'	69.17'
Axle Loading (Maximum Weight per Axle)
Weight on Drivers	150000 lbs	157250 lbs	165500 lbs
Engine Weight	237000 lbs	253965 lbs	259800 lbs
Tender Light Weight	148000 lbs	148000 lbs	148000 lbs
Total Engine and Tender Weight	385000 lbs	401965 lbs	407800 lbs
Tender Water Capacity	8000 gals	8000 gals	8000 gals
Tender Fuel Capacity (oil/coal)	13 tons	13.5 tons	13.5 tons
Minimum weight per yard of rail on which locomotive could run	83.33 lb rail	87.36 lb rail	91.94 lb rail
	Geometry Relating to Tractive Effort
Driver Diameter	69"	72"	72"
Boiler Pressure	200 psi	190 psi	200 psi
Cylinders (dia x stroke)	23" x 28"	24" x 28"	25" x 28"
Tractive Effort	36493 lbs	36176 lbs	41319 lbs
Factor of Adhesion (Weight on Drivers/Tractive Effort)	4.11	4.35	4.01
	Heating Ability
Firebox Area	262 sq. ft	269.80 sq. ft	328 sq. ft
Grate Area	50.40 sq. ft	66.50 sq. ft	66.50 sq. ft
Evaporative Heating Surface	2983	3823	3881
Superheating Surface	590	810	810
Combined Heating Surface	3573	4633	4691
Evaporative Heating Surface/Cylinder Volume	221.55	260.76	243.97
	Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation	10080	12635	13300
Same as above plus superheater percentage	11744.48	14844.01	15596.53
Same as above but substitute firebox area for grate area	61052.67	60224.27	76927.22
Power L1	16403.82	19380.54	19327.70
Power MT	723.28	815.14	772.39