In 1904, Seaboard subsidiary Atlanta and Birmingham Air Line Railway, purchased the previous year, completed construction and extended the Atlanta route to Birmingham, Alabama, the largest center of iron and steel production in the South, and a valuable endpoint for the Seaboard which had grown to a 2600 mile system. In 1926, an extension from the main line at Coleman, Florida, to West Palm Beach and Miami was completed.
The best known SAL train was an all sleeper car train carrying tourists from New York City down to resorts in Florida known as the "Orange Blossom Special". The train originated in 1925, and was immortalized in an extremely famous fiddle tune of the same name. Other Florida trains were the Silver Meteor and the Silver Star.
The first "Mikado" type locomotives on the Seaboard Air Lines arrived in 1914. There were nineteen delivered from the American Locomotive Company which were designated as Class Q and assigned road numbers 300 through 318. These locomotives had 63" drivers, 27" x 30" cylinders, a 185 psi boiler pressure and they exerted 54,588 pounds of tractive effort and each weighed 282,000 pounds. The firebox was 247 square feet, the evaporative heating surface was 3,537 square feet and with the superheater the combined heating surface was 4,295 square feet. .The Class Q locomotives were hand-fired and were delivered with Vanderbilt tenders.
In 1918, ten "Mikado-Light" locomotives were allocated by the USRA to the SAL. They were designated as Class Q-1 and given road numbers 390 through 399 and were renumbered 490 through 499 in 1925 to make room for more ALCO-built 2-8-2s. These locomotives had 63" drivers, 27" x 30" cylinders, a 200 psi boiler pressure and they exerted 54,725 pounds of tractive effort and each weighed 292,000 pounds. The firebox was 280 square feet, the evaporative heating surface was 3,783 square feet and with the superheater the combined heating surface was 4,665 square feet.
In 1922, ALCO delivered fifteen of what would be designated as Class Q-2 locomotives. The "Mikados" were very similar to the Q-1 and were assigned road numbers 319-333. These locomotives had 63" drivers, 27" x 30" cylinders, a 185 psi boiler pressure and they exerted 54,588 pounds of tractive effort and each weighed 284,800 pounds. The firebox was 247 square feet, the evaporative heating surface was 3,537 square feet and with the superheater the combined heating surface was 4,295 square feet. .
The next group of 2-8-2s arrived in 1923, and this group of twenty-three locomotives was assigned road numbers 334 through 356 and designated as Class Q-3. The Class Q-3s had 63" drivers, 26" x 30" cylinders, a 200 psi boiler pressure and they exerted 54,724 pounds of tractive effort and each weighed 300,000 pounds. The firebox was 291 square feet, the evaporative heating surface was 3,786 square feet and with the superheater the combined heating surface was 4,668 square feet. .They were equipped with a Delta trailing truck booster, which raised the tractive effort to 65,200 pounds. In the following three years the SAL took delivery of ninety-four more Class Q-3s. ALCO built twenty with road numbers 377 through 396 and seventy-four were built by the Baldwin Locomotive Works with road numbers 357 through 376 and 397 through 450.
There was one more Class Q-3 on the SAL. In August 1930 number 441's boiler exploded and the locomotive was severely damaged. A new boiler was built and the locomotive was rebuilt in the Portsmouth Shops in 1931. The SAL renumbered the rebuilt locomotive 451.
Eight more "Mikados" were added to the roster in 1942. The SAL acquired ALCO-built ex Wabash numbers 2414 and 2415 and Baldwin-built ex Wabash numbers 2424, 2427, 2434, 2436, 2439 and 2440.
There are no surviving Seaboard Air Line Railroad 2-8-2 "Mikado" type locomotives.
|Class||Qty.||Road Numbers||From Other RR||Year Acquired||Year Built||Builder||Notes|
Originally, the superheat surface area was estimated from the calculation of the area of the flues and a calculated average ratio based on more than 350 locomotive entries in Locobase where both flue surface area and superheater areas are known. 758 sq ft seemed a close fit that likely slightly understated the real area. And in fact the table in the May 1916 issue of Railway Mechanical Engineer (RME) gave the superheat value as 759 sq ft
Although these first Mikados on the Seaboard came with 27" cylinders and a boiler pressed to 185 psi (54,600 lb TE), Langley and Beckum (in Drury, 1993) comment that the combination "proved less than optimal."
Sometime after 1929, they were modified with 26" cylinders and 200 lb psi (as found in the Q3s) and later also received mechanical stokers.
The last in this class was retired in 1952.
Much of the data comes from [external link] for 1929 locomotive diagrams. Superheat surface area is estimated from the calculation of the area of the flues and a calculated average ratio based on more that 350 locomotive entries in Locobase where both flue surface area and superheater areas are known. It's a close fit that likely slightly understates the real area.
Langley and Beckum (in Drury, 1993) may comment that the combination of 27" cylinders and 185-psi boilers "proved less than optimal", but that must have been well after the Q-class Mikados entered service. Eight years after the first batch came this set from Schenectady and fitted with Baker valve gear.
Like the Qs, these engine were modified to Q3 standards sometime after 1929 and later also received mechanical stokers. The last in this class was retired in 1952.
Based on the USRA's light Mikado (Locobase 40) according to Langley and Beckum (in Drury, 1993), but with differences, particularly in the firebox. The most notable of these externally was the extra 17" between the leading truck and the first driver, giving the engine a long-striding look. Air pumps hung on the smokebox (like those on the C&O), and the cast trailing truck had a booster, too. Firebox heating surface included 26 sq ft of arch tubes.
Alco-Schenectady, Alco-Richmond, and Baldwin shared in the order, which was delivered from 1923-1931. Baldwin works numbers were 58019-58020, 58026-58039 in September in 1924; 58070-58073 in November; 58651-58653 in September 1925; 58718-58723, 58752-58753, 58765-58767 in October; 58967-58976 in January 1926; 59030-59046 in February; 59088-59089 in March; 59099-59109 in April.
Another engine was later constructed out of 441's running gear and a new boiler.
The last engine retired in 1955.
|Principal Dimensions by Steve Llanso of Sweat House Media|
|Railroad||Seaboard Air Line (SAL)||Seaboard Air Line (SAL)||Seaboard Air Line (SAL)|
|Number in Class||19||15||117|
|Locomotive Length and Weight|
|Driver Wheelbase (ft / m)||16.67 / 5.08||16.67 / 5.08||16.75 / 5.11|
|Engine Wheelbase (ft / m)||34.75 / 10.59||34.75 / 10.59||37.83 / 11.53|
|Ratio of driving wheelbase to overall engine wheebase||0.48||0.48||0.44|
|Overall Wheelbase (engine & tender) (ft / m)||72.56 / 22.12||72.15 / 21.99||74.89 / 22.83|
|Axle Loading (Maximum Weight per Axle) (lbs / kg)||52,300 / 23,723||52,600 / 23,859||53,000 / 24,040|
|Weight on Drivers (lbs / kg)||207,500 / 94,121||209,000 / 94,801||212,000 / 96,162|
|Engine Weight (lbs / kg)||282,000 / 127,913||283,000 / 128,367||300,000 / 136,078|
|Tender Loaded Weight (lbs / kg)||181,000 / 82,100||183,800 / 83,370||190,600 / 86,455|
|Total Engine and Tender Weight (lbs / kg)||463,000 / 210,013||466,800 / 211,737||490,600 / 222,533|
|Tender Water Capacity (gals / ML)||9000 / 34.09||9000 / 34.09||9600 / 36.36|
|Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT)||17 / 15.50||17 / 15.50||16 / 14.50|
|Minimum weight of rail (calculated) (lb/yd / kg/m)||86 / 43||87 / 43.50||88 / 44|
|Geometry Relating to Tractive Effort|
|Driver Diameter (in / mm)||63 / 1600||63 / 1600||63 / 1600|
|Boiler Pressure (psi / kPa)||185 / 12.80||185 / 12.80||200 / 13.80|
|High Pressure Cylinders (dia x stroke) (in / mm)||27" x 30" / 686x762||27" x 30" / 686x762||26" x 30" / 660x762|
|Tractive Effort (lbs / kg)||54,588 / 24760.73||54,588 / 24760.73||54,724 / 24822.42|
|Factor of Adhesion (Weight on Drivers/Tractive Effort)||3.80||3.83||3.87|
|Firebox Area (sq ft / m2)||247 / 22.96||247 / 22.96||291 / 27.04|
|Grate Area (sq ft / m2)||63.18 / 5.87||63.20 / 5.87||63.20 / 5.87|
|Evaporative Heating Surface (sq ft / m2)||3537 / 328.72||3537 / 328.72||3786 / 351.86|
|Superheating Surface (sq ft / m2)||758 / 70.45||758 / 70.45||882 / 81.97|
|Combined Heating Surface (sq ft / m2)||4295 / 399.17||4295 / 399.17||4668 / 433.83|
|Evaporative Heating Surface/Cylinder Volume||177.91||177.91||205.37|
|Computations Relating to Power Output (More Information)|
|Robert LeMassena's Power Computation||11,688||11,692||12,640|
|Same as above plus superheater percentage||13,792||13,797||15,042|
|Same as above but substitute firebox area for grate area||53,920||53,920||69,258|