In 1968 the TC was liquidated and parts of it were bought by the IC, L&N and the Southern Railway. The Tennessee Central endured for over 80 years in the face of very tough odds, and played a considerable part in the economic development of its service region.
The Tennessee Central purchased most of its motive power second hand. However, it did buy twelve new "Mikados" from the American Locomotive Company, eight in1922 and four more in 1926
The eight "Mikados" ALCO delivered in 1922 were given road numbers 601 through 608. These locomotives had 56" diameter drivers, 22" x 28" cylinders, a 200 psi boiler pressure, they exerted 41,140 pounds of tractive effort and each weighed 208,050 pounds. The firebox was 165 square feet, the evaporative heating surface was 3,175 square feet and with the superheater the combined heating surface was 3,827.
In 1926, the four 2-8-2s ALCO delivered were assigned road numbers 701 through 704. These locomotives had 57" diameter drivers, 25" x 30" cylinders, a 200 psi boiler pressure, they exerted 55,921 pounds of tractive effort and each weighed 283,536 pounds. The firebox was 218 square feet, the evaporative heating surface was 2,439 square feet and with the superheater the combined heating surface was 3,341.
There were six other Mikados" on the TC that were bought second-hand. Three locomotives were bought in 1937 from the New York Central and assigned road numbers 725 through 727 and three bought from the CCC&StL in 1938 and assigned road numbers 728 through 730.
There are no surviving TC 2-8-2 "Mikado" type locomotives.
| Qty. | Road Numbers | From Other RR | Year Acquired | Year Built | Builder | Notes |
|---|---|---|---|---|---|---|
| 8 | 601-608 | 1922 | ALCO | 1 | ||
| 4 | 701-704 | 1924 | ALCO | 2 | ||
| 1 | 725 | NYC | 1937 | 1906 | ALCO | 3 |
| 1 | 726 | NYC | 1937 | 1905 | ALCO | 4 |
| 1 | 727 | NYC | 1937 | 1905 | ALCO | 5 |
| 1 | 728 | CCC&StL | 1938 | 1907 | ALCO | 6 |
| 1 | 729 | CCC&StL | 1938 | 1907 | ALCO | 7 |
| 1 | 730 | CCC&StL | 1938 | 1906 | ALCO | 8 |
Data from TC 1941ca Locomotive Diagrams and Miscellaneous Data supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.
One of the key factors in the type of locomotives procured by the TC was the relatively small budget the contractors had when they built the railroad; see Locobase 7344 for a summary of the TC's history. As a result, axle loadings were relatively low. These Mikados (Alco works #63317-63324) show the effects of such constraints. Compared to the mainline 2-8-2s being built to the USRA designs (or variations thereof), these were small locomotives with small drivers. They slogged rather than loped.
Only two years later, however, the railroad went for considerably bigger engines. See Locobase 7349.
Data from TC 1941ca Locomotive Diagrams and Miscellaneous Data supplied in May 2005 and TC 1 -1929 Summary of Locomotives in 2016 by Allen Stanley from his extensive Rail Data Exchange.(Many thanks to Chris Hohl for his 29 November 2015 email that included the Builder's Card for this class to correct errors in the Locobase entry. Thanks to Steve Low for his 2 May 2020 email querying boiler pressures.) Works numbers were 65282-65285 in June 1924.
Although the first and larger class of Mikados delivered to the TC were quite small (Locobase 7348), the next group -- this quartet from Richmond owed a lot to the USRA Light 2-8-2 design (Locobase 40). For one thing, the axle loading increased by 25%, tractive effort followed suit and the result was a relatively large locomotive.
The biggest difference from the USRA's Light Mikado was in the impressive increase in the ratio of superheater to overall heating surface -- this was a hot engine with lots of superheat and a big firebox. Firebox heating surface included 27 sq ft (2.51 sq m) in arch tubes. Driver diameter still was scaled to the many ups and downs of the TC mainline and measured considerably less than the by-then-standard 63". That resulted in a higher tractive effort.
In 1929, the Summary of Locomotives offered the unusual boiler pressure shown in the specs. By 1941, the TC recorded the engines loaded weight as 283,536 lb (128,610 kg) and the boiler pressure as 200 psi (13.79 bar).
For some reason, the 1941 book showed the 704 on a separate page, probably because it pulled a larger, 11,500-gallon tender.
All but 703 were off the roster by January 1953. 703 was shown as a "standby" engine.
| Principal Dimensions by Steve Llanso of Middle Run Media | ||
|---|---|---|
| Class | 601 | 701 |
| Locobase ID | 7348 | 7349 |
| Railroad | Tennessee Central | Tennessee Central |
| Country | USA | USA |
| Whyte | 2-8-2 | 2-8-2 |
| Number in Class | 8 | 4 |
| Road Numbers | 601-608 | 701-704 |
| Gauge | Std | Std |
| Number Built | 8 | 4 |
| Builder | Alco-Brooks | Alco-Richmond |
| Year | 1922 | 1924 |
| Valve Gear | Walschaert | Walschaert |
| Locomotive Length and Weight | ||
| Driver Wheelbase (ft / m) | 15 / 4.57 | 15 / 4.57 |
| Engine Wheelbase (ft / m) | 33 / 10.06 | 33.58 / 10.24 |
| Ratio of driving wheelbase to overall engine wheelbase | 0.45 | 0.45 |
| Overall Wheelbase (engine & tender) (ft / m) | 64.92 / 19.79 | 67.60 / 20.60 |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | 39,500 / 17,917 | |
| Weight on Drivers (lbs / kg) | 158,000 / 71,668 | 221,000 / 100,244 |
| Engine Weight (lbs / kg) | 208,050 / 94,370 | 279,000 / 126,552 |
| Tender Loaded Weight (lbs / kg) | 159,300 / 72,257 | 166,800 / 75,659 |
| Total Engine and Tender Weight (lbs / kg) | 367,350 / 166,627 | 445,800 / 202,211 |
| Tender Water Capacity (gals / ML) | 8000 / 30.30 | 9000 / 34.09 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 14 / 13 | 14 / 13 |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | 66 / 33 | 92 / 46 |
| Geometry Relating to Tractive Effort | ||
| Driver Diameter (in / mm) | 56 / 1422 | 57 / 1448 |
| Boiler Pressure (psi / kPa) | 200 / 1380 | 193 / 1310 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 22" x 28" / 559x711 | 25" x 30" / 635x762 |
| Tractive Effort (lbs / kg) | 41,140 / 18660.81 | 53,964 / 24477.69 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 3.84 | 4.10 |
| Heating Ability | ||
| Tubes (number - dia) (in / mm) | 160 - 2" / 51 | 219 - 2" / 51 |
| Flues (number - dia) (in / mm) | 28 - 5.375" / 137 | 38 - 5.375" / 137 |
| Flue/Tube length (ft / m) | 19.25 / 5.87 | 19.25 / 5.87 |
| Firebox Area (sq ft / m2) | 165 / 15.33 | 245 / 22.76 |
| Grate Area (sq ft / m2) | 47.80 / 4.44 | 66.80 / 6.21 |
| Evaporative Heating Surface (sq ft / m2) | 2536 / 235.60 | 3466 / 322 |
| Superheating Surface (sq ft / m2) | 652 / 60.57 | 902 / 83.80 |
| Combined Heating Surface (sq ft / m2) | 3188 / 296.17 | 4368 / 405.80 |
| Evaporative Heating Surface/Cylinder Volume | 205.84 | 203.40 |
| Computations Relating to Power Output (More Information) | ||
| Robert LeMassena's Power Computation | 9560 | 12,892 |
| Same as above plus superheater percentage | 11,472 | 15,600 |
| Same as above but substitute firebox area for grate area | 39,600 | 57,215 |
| Power L1 | 13,983 | 13,782 |
| Power MT | 780.44 | 549.94 |
