Missouri-Kansas-Texas / Wichita Falls & Northwestern 2-8-0 "Consolidation" Locomotives in the USA


Class Details by Steve Llanso of Sweat House Media

Class 22 (Locobase 13701)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University, Volume 36, p 66. Works numbers were 36182-36185 in March 1911.

Not long after the Wichita Falls Route took delivery of these Consolidations, they sold the quartet to the Missouri-Kansas-Texas, which renumbered them 913-916. 914 was sold to the Kansas City, Mexico & Orient.


Class G (Locobase 7729)

Data from MKT 1903 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. See also Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University Vol 19, p. 256. Works numbers were 13740-13741, 13745, 13751-13752 in September 1893.

Baldwin supplied Consolidations in both compound- and simple-expansion variants. The compounds came first, using a cylinder volume identical to that of the F-class Ten-wheelers supplied in the same year. The specifications page archived in the DeGolyer Library show that this class was ordered with 15" HP and 25" LP cylinders.


Class G1 / K-6-c (Locobase 7730)

Data from MKT 1903 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. See also DeGolyer, Volume 19, p. 163. Works numbers were 14078-14082 in August 1894, 14297-14300 in April 1895.

A year after Baldwin delivered compound Consolidations (Locobase 7729), they supplied the simple-expansion counterparts shown in this entry. 230 and 240-245 were produced in 1894, 246-250 arrived in 1895. They were delivered trailing tenders with loaded weights of 82,000 lb (37,195 kg).

The grate grew wider although overall firebox heating surface remained essentially unchanged, which suggests that the grate had been repositioned over the drivers rather than between the frames.

These were later superheated; see Locobase 7744.


Class G2/K-7 (Locobase 7731)

Data from MKT 1903 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.Works numbers were 25082-25086 in August 1902.

Although Schenectady's boiler certainly was equal to supplying the cylinders in these Consolidations and the grate area is clearly sufficient, the reported firebox heating surface is far from enough.

All were superheated in 1917; see Locobase 16154.


Class G3/K-6b (Locobase 7737)

Data from MKT 1903 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. See also DeGolyer, Volume 19, p. 269. Works number was 14347.

The camelback locomotive layout operated almost exclusively in the anthracite regions of Pennsylvania that had seen its invention by John Wootten in the 1870s. Once in a great while, though, other railroads would sample the big firebox. According to Drury (1993), the Katy's adoption of the few they acquired was motivated by a wish to burn the low-grade coal they were extracting from mines near McAlester, Oklahoma.

The first such engine for the Katy was this Baldwin product, which was unusually lavish in its accommodations for the fireman in the rear -- the overhead canopy even had windows. The engineer's cab, which straddled the boiler over the second and third drivers, had a clerestory and three panes a side. The specs report that the firebox was based directly on a Reading design and showed a heating surface area of 223 sq ft (20.72 sq m). By 1904, however, the firebox was 2" shorter and possibly the combustion chamber had been reduced as well.

As with the other camelbacks, this one would be rebuilt as a conventional-cab engine in June 1909.

It was sold for scrap in October 1924 to Hyman Michaels Company.


Class G4/K-6-b (Locobase 7739)

Data from MKT 1903 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. See also DeGolyer, Volume 22, p. 285 and Volume 24, p. 47. (Thanks to Chris Hohl for his 6 June 2017 email noting the correct coal capacity and an earlier email reporting the original boiler pressure.) Works numbers were 18103 in September 1900 and 19391 in August 1901.

As noted in Locobase 7737, the camelback was rare outside of Pennsylvania. But the Katy had some low-calorie coal coming out of its McAlester mines and wanted to burn it in the wide Wootten fireboxes. A few years after the single G3, the railroad bought two G4s, which were a bit bigger and had longer boilers. They also had much shorter combustion chambers. Their boilers were delivered set to pop at 190 psi (13.1 bar), but were soon reset to the 200 psi shown in the specs.

Like the G3, they were converted to conventional cab engines. 437 was modified in September 1909 and the 432 in October 1910.


Class G5/K-8 (Locobase 7740)

Data from MKT 1903 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. See also DeGolyer, Volume 25, p. 39. Works number was 21389 in December 1902.

Continuing its acquisition of a few camelbacks (see Locobases 7738 & 7739), the Katy acquired this substantially larger example a year after the second of the two G4s was delivered. Little increased in grate, the firebox actually had a little less heating surface overall. The tubes were longer and there were more of them, hence the generous evaporative heating surface area.

The last of its kind, this camelback was converted to a conventional cab in 1913; it now fell in with the 492-493 (Locobase 7742) in the K-8 class. Another rebuild in 1925 fitted the K-8 class with a superheater and piston valves (Locobase 7743).


Class G6/K-6-a (Locobase 7741)

Data from MKT 1903 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. See also DeGolyer, Volume 22, p. 284 and Volume 24, p. 46. Works numbers were 18072 in August 1900 and 19332-19335 in August 1901.

Apparently the Katy wanted to compare the two G4s (which had Wootten fireboxes and are shown in Locobase 7739) with the conventional firebox that had half the grate area. Interestingly, the latter's total firebox heating surface was only 27 sq ft (2.51 sq m) less than the much broader grate.

The Katy's diagram book shows higher weights of 147,215 lb (66,776 kg) on the drivers and engine weight of 161,415 lb (73,217 kg).


Class G7/K-8 (Locobase 7742)

Data from MKT 1903 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. See also DeGolyer, Volume 25, p. 38. Works numbers were 21326-21327 in November 1902.

The Katy appears to have been sampling firebox designs as they built locomotives with similar boiler dimensions, but three quite different widths of fireboxes. The camelbacks, fitted with 96" (2,438 mm) wide furnaces, appear in Locobase 7739. The typical narrow firebox with the grate positioned above the frame (41"/1,041 mm, and thus wider than the traditional 34" grate), appeared in the 431 and 433-436 shown in Locobase 7741. So this pair took the middle road, entering service a year later with 66" (1,676 mm) fireboxes.

They were later superheated; see Locobase 7743


Class K-10 (Locobase 7738)

Data from MKT 5 1939 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

According to Drury (1993) this class of Consolidations, purchased "...after a decade of tentativeness", was delivered with 22" diameter cylinders and 61" diameter drivers. Locobase doesn't know for sure when they might have been upgraded as shown in the specs.

They didn't enjoy particularly long lives as they were supplanted in road service by the Mikados and were too big and heavy to displace the 2-6-0s on branch-line operations. Almost all had been scrapped by 1940.


Class K-6-c - superheated (Locobase 7744)

Data from MKT 5 1939 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

Locobase is intrigued by the Katy's willingness to update Consolidations of such small size and advanced age (1894 - see Locobase 7730 for their data on delivery). In contrast to many such conversions to superheating, the modification sacrificed little heating surface area. Also, the flues had the larger of the two diameters characteristic of the Type A superheater.


Class K-7 - superheater (Locobase 16154)

Data from LR&N CO 1 1925 Locomotive Diagrams supplied in August 2013 by Allen Stanley from his extensive Rail Data Exchange.

The saturated-steam Consolidations delivered in 1902 (Locobase 7731) were all fitted with superheaters in 1917. It was a typical tradeoff of tubes and flues that resulted in an adequate power upgrade. Piston valves replaced slide valves, but the quintet still used Stephenson link motion to actuate them.

NB: Superheater area is an estimated based on other US locomotives with similar superheater installations.

Twenty years after they entered Katy service, the entire class was transferred in April 1923 to the Louisiana Railway & Navigation to run on the L&A of Texas.


Class K-8 - superheated (Locobase 7743)

Data from MKT 5 1939 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

The original pair of K-8 conventional Consolidations (Locobase 7742) was superheated in the 1920s along with the rebuilt 494 (originally a camelback) with the usual trade-off of evaporative heating surface for superheater area.

Principal Dimensions by Steve Llanso of Sweat House Media
Class22GG1 / K-6-cG2/K-7G3/K-6b
Locobase ID13,701 7729 7730 7731 7737
RailroadWichita Falls & Northwestern (MKT)Missouri-Kansas-Texas (MKT)Missouri-Kansas-Texas (MKT)Missouri-Kansas-Texas (MKT)Missouri-Kansas-Texas (MKT)
CountryUSAUSAUSAUSAUSA
Whyte2-8-02-8-02-8-02-8-02-8-0
Number in Class471251
Road Numbers22-25 / 913-916 / 1104, 1106-1107231, 234-239230, 240-250438-442251
GaugeStdStdStdStdStd
Number Built471251
BuilderBaldwinBurnham, Williams & CoBurnham, Williams & CoSchenectadyBurnham, Williams & Co
Year19111893189419011895
Valve GearStephensonStephensonStephensonStephensonStephenson
Locomotive Length and Weight
Driver Wheelbase (ft / m)15 / 4.5714.92 / 4.5515.08 / 4.6017 / 5.1815.08 / 4.60
Engine Wheelbase (ft / m)23 / 7.0122.92 / 6.9923.08 / 7.0325.50 / 7.7723.08 / 7.03
Ratio of driving wheelbase to overall engine wheebase 0.65 0.65 0.65 0.67 0.65
Overall Wheelbase (engine & tender) (ft / m)49.33 / 15.0450.65 / 15.4453.02 / 16.1654.46 / 16.60
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)130,000 / 58,967134,100 / 60,827143,238 / 64,972144,000 / 65,317136,500 / 61,915
Engine Weight (lbs / kg)145,000 / 65,771147,600 / 66,950156,322 / 70,907165,500 / 75,070148,600 / 67,404
Tender Loaded Weight (lbs / kg)115,000 / 52,16386,720 / 39,33698,078 / 44,487107,500 / 48,761111,400 / 50,530
Total Engine and Tender Weight (lbs / kg)260,000 / 117,934234,320 / 106,286254,400 / 115,394273,000 / 123,831260,000 / 117,934
Tender Water Capacity (gals / ML)6000 / 22.734000 / 15.154300 / 16.295200 / 19.705000 / 18.94
Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT)8 / 7.3010 / 9.1011 / 1013 / 11.80
Minimum weight of rail (calculated) (lb/yd / kg/m)54 / 2756 / 2860 / 3060 / 3057 / 28.50
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)56 / 142256 / 142256 / 142260 / 152456 / 1422
Boiler Pressure (psi / kPa)180 / 12.40190 / 13.10180 / 12.40200 / 13.80180 / 12.40
High Pressure Cylinders (dia x stroke) (in / mm)20" x 26" / 508x66014" x 26" / 356x66021" x 26" / 533x66020" x 30" / 508x76221" x 26" / 533x660
Low Pressure Cylinders (dia x stroke) (in / mm)24" x 26" / 610x660
Tractive Effort (lbs / kg)28,414 / 12888.3921,931 / 9947.7531,327 / 14209.7134,000 / 15422.1631,327 / 14209.71
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.58 6.11 4.57 4.24 4.36
Heating Ability
Firebox Area (sq ft / m2)156 / 14.49168 / 15.61165.32 / 15.36143 / 13.29211 / 19.61
Grate Area (sq ft / m2)30.80 / 2.8625.40 / 2.3632.20 / 2.9946.50 / 4.3276 / 7.06
Evaporative Heating Surface (sq ft / m2)2136 / 198.441784 / 165.801739 / 161.562876 / 267.291869 / 173.70
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)2136 / 198.441784 / 165.801739 / 161.562876 / 267.291869 / 173.70
Evaporative Heating Surface/Cylinder Volume225.94385.11166.84263.65179.32
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation554448265796930013,680
Same as above plus superheater percentage554448265796930013,680
Same as above but substitute firebox area for grate area28,08031,92029,75828,60037,980
Power L151823418413565844713
Power MT351.52224.77254.57403.20304.48

Principal Dimensions by Steve Llanso of Sweat House Media
ClassG4/K-6-bG5/K-8G6/K-6-aG7/K-8K-10
Locobase ID7739 7740 7741 7742 7738
RailroadMissouri-Kansas-Texas (MKT)Missouri-Kansas-Texas (MKT)Missouri-Kansas-Texas (MKT)Missouri-Kansas-Texas (MKT)Missouri-Kansas-Texas (MKT)
CountryUSAUSAUSAUSAUSA
Whyte2-8-02-8-02-8-02-8-02-8-0
Number in Class215240
Road Numbers432, 437494/670431, 433-436/608-612492-493/668-669616-655
GaugeStdStdStdStdStd
Number Built215240
BuilderBurnham, Williams & CoBurnham, Williams & CoBurnham, Williams & CoBurnham, Williams & CoAlco-Schenectady
Year19001902190019021910
Valve GearStephensonStephensonStephensonStephensonWalschaert
Locomotive Length and Weight
Driver Wheelbase (ft / m)15.25 / 4.6516.33 / 4.9815.25 / 4.6516.33 / 4.9816.75 / 5.11
Engine Wheelbase (ft / m)23.33 / 7.1124.92 / 7.6023.33 / 7.1124.81 / 7.5625.58 / 7.80
Ratio of driving wheelbase to overall engine wheebase 0.65 0.66 0.65 0.66 0.65
Overall Wheelbase (engine & tender) (ft / m)51.65 / 15.7452.69 / 16.0651.65 / 15.7453.79 / 16.4062.92 / 19.18
Axle Loading (Maximum Weight per Axle) (lbs / kg)49,750 / 22,566
Weight on Drivers (lbs / kg)151,915 / 68,908156,500 / 70,987144,000 / 65,317156,970 / 71,200199,000 / 90,265
Engine Weight (lbs / kg)166,815 / 75,666180,000 / 81,647157,500 / 71,441178,170 / 80,817223,000 / 101,151
Tender Loaded Weight (lbs / kg)111,400 / 50,530136,000 / 61,689111,400 / 50,530136,000 / 61,689159,000 / 72,121
Total Engine and Tender Weight (lbs / kg)278,215 / 126,196316,000 / 143,336268,900 / 121,971314,170 / 142,506382,000 / 173,272
Tender Water Capacity (gals / ML)4300 / 16.296000 / 22.734300 / 16.296000 / 22.738300 / 31.44
Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT)13 / 11.8012 / 10.9010 / 9.1012 / 10.9014 / 12.70
Minimum weight of rail (calculated) (lb/yd / kg/m)63 / 31.5065 / 32.5060 / 3065 / 32.5083 / 41.50
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)56 / 142256 / 142256 / 142256 / 142263 / 1600
Boiler Pressure (psi / kPa)200 / 13.80200 / 13.80200 / 13.80200 / 13.80195 / 13.40
High Pressure Cylinders (dia x stroke) (in / mm)21" x 26" / 533x66022" x 28" / 559x71121" x 26" / 533x66022" x 28" / 559x71124" x 30" / 610x762
Tractive Effort (lbs / kg)34,808 / 15788.6641,140 / 18660.8134,808 / 15788.6641,140 / 18660.8145,463 / 20621.69
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.36 3.80 4.14 3.82 4.38
Heating Ability
Firebox Area (sq ft / m2)195 / 18.12190 / 17.65168.20 / 15.63167 / 15.51230 / 21.38
Grate Area (sq ft / m2)76.10 / 7.0776.20 / 7.0832 / 2.9748.60 / 4.5249.50 / 4.60
Evaporative Heating Surface (sq ft / m2)2084 / 193.612837 / 263.561979 / 183.762646 / 245.822745 / 255.11
Superheating Surface (sq ft / m2)600 / 55.76
Combined Heating Surface (sq ft / m2)2084 / 193.612837 / 263.561979 / 183.762646 / 245.823345 / 310.87
Evaporative Heating Surface/Cylinder Volume199.94230.29189.87214.79174.75
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation15,22015,240640097209653
Same as above plus superheater percentage15,22015,2406400972011,390
Same as above but substitute firebox area for grate area39,00038,00033,64033,40052,923
Power L1547857385050527512,116
Power MT317.99323.33309.26296.35536.91

Principal Dimensions by Steve Llanso of Sweat House Media
ClassK-6-c - superheatedK-7 - superheaterK-8 - superheated
Locobase ID7744 16,154 7743
RailroadMissouri-Kansas-Texas (MKT)Missouri-Kansas-Texas (MKT)Missouri-Kansas-Texas (MKT)
CountryUSAUSAUSA
Whyte2-8-02-8-02-8-0
Number in Class1252
Road Numbers230, 240-250671-675668-670
GaugeStdStdStd
Number Built
BuilderMKTMKTMKT
Year192319171923
Valve GearStephensonStephensonStephenson
Locomotive Length and Weight
Driver Wheelbase (ft / m)15.08 / 4.6017 / 5.1816.33 / 4.98
Engine Wheelbase (ft / m)23.08 / 7.0325.33 / 7.7224.92 / 7.60
Ratio of driving wheelbase to overall engine wheebase 0.65 0.67 0.66
Overall Wheelbase (engine & tender) (ft / m)55.87 / 17.0355.07 / 16.7955.50 / 16.92
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)153,200 / 69,490147,000 / 66,678166,700 / 75,614
Engine Weight (lbs / kg)167,700 / 76,068168,400 / 76,385187,300 / 84,958
Tender Loaded Weight (lbs / kg)102,800 / 46,629107,500 / 48,761160,400 / 72,756
Total Engine and Tender Weight (lbs / kg)270,500 / 122,697275,900 / 125,146347,700 / 157,714
Tender Water Capacity (gals / ML)5000 / 18.946000 / 22.738000 / 30.30
Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT)2224 / 8.402661 / 10.102661 / 10.10
Minimum weight of rail (calculated) (lb/yd / kg/m)64 / 3261 / 30.5069 / 34.50
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)56 / 142260 / 152456 / 1422
Boiler Pressure (psi / kPa)180 / 12.40195 / 12.40200 / 13.80
High Pressure Cylinders (dia x stroke) (in / mm)21" x 26" / 533x66020" x 30" / 508x76222" x 28" / 559x711
Tractive Effort (lbs / kg)31,327 / 14209.7133,150 / 15036.6041,140 / 18660.81
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.89 4.43 4.05
Heating Ability
Firebox Area (sq ft / m2)165 / 15.33138 / 12.82170 / 15.80
Grate Area (sq ft / m2)32.20 / 2.9931.10 / 2.8948.60 / 4.52
Evaporative Heating Surface (sq ft / m2)1448 / 134.572109 / 195.931940 / 180.30
Superheating Surface (sq ft / m2)335 / 31.13435560 / 52.04
Combined Heating Surface (sq ft / m2)1783 / 165.702544 / 195.932500 / 232.34
Evaporative Heating Surface/Cylinder Volume138.93193.34157.48
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation579660659720
Same as above plus superheater percentage6897709511,858
Same as above but substitute firebox area for grate area35,34331,48541,480
Power L1852312,00211,864
Power MT490.60720.00627.61

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