In 1912, the AT&N joined with the Tombigbee Valley Railroad at Riderwood. (The TVR then connected the delightfully named Nannahubba with Silas 52 miles away.) And a year later the union was solemnized in the name of the Alabama, Tennessee & Northern Railroad Company.
Over the next 16 years the railroad reached toward Mobile over the former TVR line via Calvert, eventually arriving at Mobile in 1928 over its own rails,, and amassing a total of 214 main-line miles. (It never made it anywhere close to Tennessee, by the way.)
It was in this same year that the railroad ordered these three light decapods. Part of the flurry of purchases of the same design, mostly by southern roads, the engines offered a useful amount of tractive effort on a relatively light axle-loading. Piston valves measured 12" (306 mm) in diameter. Firebox heating surface area included 25 sq ft (2.3 sq m) of arch tubes.
All were sold by the AT & N in 1946. Georgia Car & Locomotive purchased 401 and sold it to Woodward Iron Company as their 41. WIC sold 41 to the Mid-Continent Railway Museum in 1964.
402 went on to serve the Gainesville Midland as 203 until 1959 when it was sold to the National Railway Historical Society.
403 traveled to the Durham & Southern in 1947 to join three younger sisters delivered to the North Carolina shortline in 1930 and 1933 (see Locobase 11370). Renumbered 203 in 1953, it was retired in 1954.
Frisco acquired the AT&N as a wholly owned subsidiary
|Specifications by Steve Llanso of Sweat House Media|
|Railroad||Alabama, Tennessee & Northern|
|Number in Class||3|
|Locomotive Length and Weight|
|Driver Wheelbase (ft / m)||19.67 / 6|
|Engine Wheelbase (ft / m)||28.25 / 8.61|
|Ratio of driving wheelbase to overall engine wheebase||0.70|
|Overall Wheelbase (engine & tender) (ft / m)||60.59 / 18.47|
|Axle Loading (Maximum Weight per Axle) (lbs / kg)||38,000 / 17,237|
|Weight on Drivers (lbs / kg)||190,000 / 86,183|
|Engine Weight (lbs / kg)||213,000 / 96,162|
|Tender Loaded Weight (lbs / kg)||137,500 / 64,183|
|Total Engine and Tender Weight (lbs / kg)||350,500 / 160,345|
|Tender Water Capacity (gals / ML)||7000 / 26.52|
|Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT)||10 / 10.90|
|Minimum weight of rail (calculated) (lb/yd / kg/m)||63 / 31.50|
|Geometry Relating to Tractive Effort|
|Driver Diameter (in / mm)||56 / 1422|
|Boiler Pressure (psi / kPa)||200 / 13.10|
|High Pressure Cylinders (dia x stroke) (in / mm)||24" x 28" / 610x711|
|Tractive Effort (lbs / kg)||48,960 / 22207.91|
|Factor of Adhesion (Weight on Drivers/Tractive Effort)||3.88|
|Firebox Area (sq ft / m2)||197 / 18.31|
|Grate Area (sq ft / m2)||54.30 / 5.05|
|Evaporative Heating Surface (sq ft / m2)||2343 / 217.75|
|Superheating Surface (sq ft / m2)||553 / 51.39|
|Combined Heating Surface (sq ft / m2)||2896 / 269.14|
|Evaporative Heating Surface/Cylinder Volume||159.81|
|Computations Relating to Power Output (More Information)|
|Robert LeMassena's Power Computation||10,860|
|Same as above plus superheater percentage||12,923|
|Same as above but substitute firebox area for grate area||46,886|