12" piston valves. This modest, but reasonably powerful 2-8-0 design was obviously satisfactory. In addition to the 9 described in Locobase 5993, Schenectady supplied these 6 (works # 62626-31) in 1921. The builder took the opportunity to go 2 better than the railroad in superheating the design, adding two flue and deleting 10 tubes. The result was a relatively high superheat fraction of combined heating surface. The given area (which the diagram books insist upon) still seems much too high. Other installations with the same count and flue length (including the BAR's G-2s of 1937 - Locobase 408) show superheater areas of less than 600 square feet.
Firebox heating surface included 21 sq ft of arch tubes. Locobase wonders about the superheater area because the boiler had the same number of flues (of the same length and diameter) as the 1921 Gs, also built by Alco (see Locobase 5994). But the area measures 76 sq ft less - Locobase still thinks the 1921 class's area was overstated.
Built in two batches in 1937 and 1945. Retired in 1951-1956.
12" piston valves. Two batches were built over 7 years. The first 3 - GA - came from Rhode Island in 1907 (works 41522-24), the other 6 from Schenectady in 1914 (works # 54944-48, 56742). The second group is credited in the diagram with one more tube (205) and apparently was superheated when delivered, but is otherwise identical except for the usual weight gain. (182,000 lb on the drivers, 210,000 total.)
The GAs were superheated in 1918. The whole class carried on until the end of steam.
| Specifications | |||
|---|---|---|---|
| Class | G -1921 | G-2 | GA/G - superheated |
| Locobase ID | 5994 | 408 | 5993 |
| Railroad | Bangor & Aroostook | Bangor & Aroostook | Bangor & Aroostook |
| Whyte | 2-8-0 | 2-8-0 | 2-8-0 |
| Road Numbers | 186-191 | 400-405 | 170-172, 180-185 |
| Gauge | Std | Std | Std |
| Builder | Alco | Alco-Schenectady | BAR |
| Year | 1921 | 1937 | 1918 |
| Valve Gear | Baker | Baker | Baker |
| Locomotive Length and Weight | |||
| Driver Wheelbase | 16.75' | 16.75' | 16.75' |
| Engine Wheelbase | 25.25' | 26.50' | 25.25' |
| Ratio of driving wheelbase to overall engine wheebase | 0.66 | 0.63 | 0.66 |
| Overall Wheelbase (engine & tender) | 58.96' | 62.67' | 58.96' |
| Axle Loading (Maximum Weight per Axle) | |||
| Weight on Drivers | 185000 lbs | 198400 lbs | 179500 lbs |
| Engine Weight | 212000 lbs | 238800 lbs | 204100 lbs |
| Tender Light Weight | 156000 lbs | 163300 lbs | 149000 lbs |
| Total Engine and Tender Weight | 368000 lbs | 402100 lbs | 353100 lbs |
| Tender Water Capacity | 7500 gals | 8500 gals | 7500 gals |
| Tender Fuel Capacity (oil/coal) | 12 tons | 12 tons | 12 tons |
| Minimum weight per yard of rail on which locomotive could run | 77.08 lb rail | 82.67 lb rail | 74.79 lb rail |
| Geometry Relating to Tractive Effort | |||
| Driver Diameter | 57" | 63" | 57" |
| Boiler Pressure | 175 psi | 225 psi | 175 psi |
| Cylinders (dia x stroke) | 23" x 30" | 22.25" x 30" | 23" x 30" |
| Tractive Effort | 41415 lbs | 45086 lbs | 41415 lbs |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 4.47 | 4.40 | 4.33 |
| Heating Ability | |||
| Firebox Area | 198 sq. ft | 212 sq. ft | 216 sq. ft |
| Grate Area | 46.70 sq. ft | 50.80 sq. ft | 46.50 sq. ft |
| Evaporative Heating Surface | 2348 | 2638 | 2391 |
| Superheating Surface | 660 | 584 | 556 |
| Combined Heating Surface | 3008 | 3222 | 2947 |
| Evaporative Heating Surface/Cylinder Volume | 162.76 | 195.40 | 165.74 |
| Computations Relating to Power Output (More Information) | |||
| Robert LeMassena's Power Computation | 8172.50 | 11430 | 8137.50 |
| Same as above plus superheater percentage | 9965.67 | 13501.73 | 9672.77 |
| Same as above but substitute firebox area for grate area | 42252.73 | 56345.81 | 44931.59 |
| Power L1 | 10692.10 | 15668.65 | 9766.71 |
| Power MT | 509.67 | 696.44 | 479.82 |
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