Missouri & North Arkansas 4-6-0 "Ten-wheeler" Locomotives of the USA


Class Details by Steve Llanso of Sweat House Media

Class 17 (Locobase 13541)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University, Volume 34, p. 119. (Thanks to Chris Hohl for his 2 June 2015 email reporting the supplemental note that changed the original specification of Stephenson valve gear to the Baker-Pilliod radial type delivered with the engines. Chris also found a 1935 photo showing the 19 operating Southern valve gear.)

See Locobase 6638 for a short history of the road, including a discussion of the 1914 accident that took 43 lives.Works numbers were 34187-34188 in January 1910.

Passenger service couldn't be slighted on the M & NA so the railroad occasionally bought a couple of new Ten-wheelers. The supplemental specs on p. 121 noted that the railroad "prefers" a lower adhesion weight of 110,000 lb (49,946 kg) that would reduce engine weight to 144,000 lb (65,317 kg) and the factor of adhesion to 4.12. It's not clear from the specs whether that or the inked-in 116,000 lb shown in Locobase's specs was the final figure.

Chris Hohl reports that the 17 was later fitted with Southern valve gear and supplied Locobase with a 1935 photo (http://www.rr-fallenflags.org/misc-m/mna-s19jpa.jpg) clearly showing the 19 aat Green Forest, Ark operating Southern gear. The picture also shows the 19 using slide valves.

The engines trailed cylindrical Vanderbilt tenders.

This pair had divergent histories. The 17 was later renumbered 19 and given 18" cylinders. It was scrapped by successor M&A in 1939. 18 apparently remained untouched and carried on after World War II before being scrapped in 1949.


Class 20 (Locobase 13272)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University, Volume 50, p. 237. See Locobase 6638 for a short history of the road, including a discussion of the 1914 accident that took 43 lives. Works number was 41297 in April 1914.

Even though the M & NA had entered into receivership by early 1914, operations needed to continue. That explains the order of a single superheated Ten-wheeler.

The 20 proved to be a durable machine. When the M & NA dieselized in 1949, the 20 was sold to the Arkansas & Ozarks. Alas for the A & O (and the 20), the engine was clapped out and was scrapped in the same year.


Class T-20 (Locobase 6638)

Data from 1903 MO & NA locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive Raildata collection.

Reorganized in 1906 from the Eureka Springs Railway, the M & NA was built in the early 1900s to connect Joplin, Mo to Helena, Ark.. Its 400-mile main line ran in a NW-SE direction across the top of Arkansas, incurring expenses that caused to be described as the most expensive railroad to be built in Arkansas. Nicknamed the May Never Arrive, it operated for more than 60 years.

It suffered some calamities, the most painful of which probably was the passenger-train collision in 1914 that killed 38 passengers and 5 crew. This accident was noteworthy in that the M&NA train was powered by Motor car No. 103 when it collided head-on with Kansas City Southern's 1st56 passenger train at a closing speed of about 70 mph. Motor car 103 was a gas-electric motor car of light steel construction, 70 feet long, weighing 47 tons, with a seating capacity of about 65 persons, according to the accident report. When KCS engine 805 (an H-2 Pacific that is described in Locobase 915) and 2 baggage cars struck the 103, the steam locomotive drove the car back 651 feet, telescoping the vehicle 20 feet at the same time. Tragically, the 105 gallons of gasoline splashed over the entire M&NA coach and burst into flames. The entire car was destroyed and most of the dead cremated without hope of rescue.

The ICC noted at the time that this was the first accident they'd reviewed involving a gas-motor car. See the full report at http://www.railaccrep.com/single.php?report=1914-036. (It's not clear if any of the 34 injured passengers and 4 crew were on the KCS train.)

Already burdened by the personal tragedy and the high cost of the 1914 accident, the M & NA was nationalized by the USRA in 1917 and, almost immediately after emerging from government control in 1920, was hit by a 15-month strike in 1921-1922 (then the longest in US history). The final blow came in 1946, when a strike forced the management to file for bankruptcy.

This diagram book must be from its early days, given the number of the locomotive. Dickson's works # was 1145.


Class T-25 (Locobase 6639)

Data from 1904 M & NA locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive Raildata collection. See Locobase 6638 for a short history of the road, including a discussion of the 1914 accident that took 43 lives.

A year after the 3 was built, the M & NA went for a duo of somewhat larger Ten-wheelers. Cooke's works # 2674 & 2675. The Baldwin Moguls (Locobase 6640) that followed a year later had very similar boiler, grate, and power dimensions.

Specifications by Steve Llanso of Sweat House Media
Class1720T-20T-25
Locobase ID13541 13272 6638 6639
RailroadMissouri & North ArkansasMissouri & North ArkansasMissouri & North ArkansasMissouri & North Arkansas
CountryUSAUSAUSAUSA
Whyte4-6-04-6-04-6-04-6-0
Number in Class2112
Road Numbers17-18/19, 182034-5
GaugeStdStdStdStd
Number Built2112
BuilderBaldwinBaldwinDicksonCooke
Year1910191419001901
Valve GearBakerWalschaertStephensonStephenson
Locomotive Length and Weight
Driver Wheelbase14.50'14.50'11.50'11.50'
Engine Wheelbase25.33'25.33'21.33'21.92'
Ratio of driving wheelbase to overall engine wheebase 0.57 0.57 0.54 0.52
Overall Wheelbase (engine & tender)59.21'57.79'57.21'51'
Axle Loading (Maximum Weight per Axle)
Weight on Drivers116000 lbs124000 lbs91500 lbs107000 lbs
Engine Weight150000 lbs168000 lbs116000 lbs130000 lbs
Tender Light Weight120000 lbs120000 lbs80000 lbs120000 lbs
Total Engine and Tender Weight270000 lbs288000 lbs196000 lbs250000 lbs
Tender Water Capacity6000 gals6000 gals4000 gals6000 gals
Tender Fuel Capacity (oil/coal)14 tons14 tons10 tons12 tons
Minimum weight of rail (calculated)64 lb/yard69 lb/yard51 lb/yard59 lb/yard
Geometry Relating to Tractive Effort
Driver Diameter63"63"57"56"
Boiler Pressure190 psi200 psi180 psi180 psi
Cylinders (dia x stroke)20" x 26"20" x 26"18" x 24"19" x 26"
Tractive Effort26660 lbs28063 lbs20872 lbs25644 lbs
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.35 4.42 4.38 4.17
Heating Ability
Firebox Area168.70 sq. ft178 sq. ft124 sq. ft145.50 sq. ft
Grate Area34.80 sq. ft35 sq. ft28 sq. ft30.28 sq. ft
Evaporative Heating Surface2381 sq. ft1885 sq. ft1653 sq. ft1957 sq. ft
Superheating Surface387 sq. ft
Combined Heating Surface2381 sq. ft2272 sq. ft1653 sq. ft1957 sq. ft
Evaporative Heating Surface/Cylinder Volume251.85199.39233.85229.37
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation6612700050405450
Same as above plus superheater percentage6612819050405450
Same as above but substitute firebox area for grate area32053416522232026190
Power L168041390154995286
Power MT387.94741.45397.48326.74


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