Boston & Maine / Fitchburg 2-6-0 "Mogul" Locomotives in the USA


Class Details by Steve Llanso of Sweat House Media

Class 161 // B-13a/b/c (Locobase 11140)

Data from Schenectady Locomotive Works, Illustrated Catalogue of Simple and Compound Locomotives (Philadelphia: J B Lippincott, 1897), pp. 130-131. See also "Mogul freighter for the Fitchburg," Railway & Locomotive Engineering Journal, Volume 8, Number 6 (June 1895), p. 338-339. See also B&M Locomotive Names and Numbers supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. 161 was works number 4317.

After the first fivesome supplied in 1893 (Locobase 11142), Schenectady delivered a much larger class of engines with taller drivers that entered service beginning in 1895. This enlarged freighter meant to ensure the guarantee mentioned in the R & LE report: "The management of this line have made a great reputation and increased their business wonderfully by offering to deliver to any point on their line by daylight any and all freight offered before six o'clock P. M. "

The B & M's well-known attachment to Moguls is shown by the class's continuing presence well into the 20th Century.


Class B-11a/b (Locobase 11144)

Data from B&M 8 - 1919 Locomotive Classification supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. See also B&M Locomotive Names and Numbers supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. Works numbers were 2873-2876 in March 1893.

Amid all of the Schenectady Moguls coming on the Fitchburg, this quintet from the Ocean State brought its own configuration. The differences included a slightly larger cylinder volume, smaller boiler (1032 had two more tubes than the others), and a slightly longer wheelbase.


Class B-12 (Locobase 11142)

Data from B&M 8 - 1919 Locomotive Classification supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. See also B&M Locomotive Names and Numbers supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

Schenectady's first set of Moguls for the Fitchburg was this quintet of low-drivered freighters. They would be followed two years later by a much larger class with taller drivers and a few more boiler tubes; see Locobase 11140.


Class B-14 (Locobase 11143)

Data from B&M 8 - 1919 Locomotive Classification and Locomotives and Tenders-Classification and Description, Boston & Maine Railroad Mechanical Department, 7 June 1928, supplied in May 2005 and August 2013, respectively, by Allen Stanley from his extensive Rail Data Exchange. See also B&M Locomotive Names and Numbers supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. Works numbers were 4544 in May 1897 and 4667-4669 in January 1898.

After the builder had delivered the big order described in Locobase 11140, it added this quartet that had a higher boiler pressure, larger grate, and a bit more weight on the drivers. But the big difference was the cross-compound arrangement that used the Richmond intercepting valve. The HP cylinder measured 21" in diameter, the LP jug had a 32" diameter.


Class B-15 syphons (Locobase 15945)

Data from B&M 1928 Locomotives and Tenders Classification and Description supplied in August 2013 by Allen Stanley from his extensive Rail Data Exchange. (Thanks to Chris Hohl for the data he found at http://www.bmrrhs.org/Archives/Steam%20Loco%20Classification%201928.06.07.pdf.)

Chris Hohl notes that the firebox heating surface area included 23.8 sq ft (2.2 sq m) in the syphon. This was apparently an experiment undertaken in the early 1920s featuring just one--road number 1406--of the B-15 class. It was unusual for a firebox to be fitted with a syphon while retaining a saturated boiler. By 1929, 1405 had been retired.


Class B-15/B-15a (Locobase 806)

Data from B & M 8 - 1919 Loco Class supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. (Thanks to Chris Hohl for his 27 December 2014 email pointing out the tender's coal capacity.)

Typical turn-of-the-century Mogul. 140 built for the B & M by Manchester (in Massachusetts) and Schenectady (New York). Manchester works numbers were

1903 May 28222-28241; August 28616-28625

1904 October 29840-29849

1905 May 30585-3059

1906 March 38981-38990; November 41441-41451

1907 42820-42834 in August; 44364-44367 in October; November 44368- 44373;

December 44740-44744

1910 (B-15a) May 47624-47633

1911 November 48960-48969.

Schenectady's works numbers were 46282-46291 in June 1909, 46292-46301 in July,

These engines operated on secondary lines until diesels superseded them in the 1950s. The 1909-1911 B-15as differed only in a slight weight gain (axle loadings of 41,666 lb (18,899 kg) were equally distributed). Many were rebuilt with piston valves, cast tender trucks, steel cab, cross-compound air pump, and centered headlight. But they kept the inside valve gear.


Class B-15b/c - superheated (Locobase 6628)

Data from B&M 6-1939 Locomotive Diagram books supplied in August 2013 by Allen Stanley from his extensive Rail Data Exchange. (Thanks to Chris Hohl for his 27 December 2014 email pointing out the tender's coal capacity and his 18 June 2015 email adding key details to the class information; see below.)

In the late 'teens, the B & M began superheating their B-15s (the originals described in Locobase 806), almost all of the B-15s were updated in the middle 1920s in a program that involved the usual exchange of many small tubes for fewer flues and piston valves (8"/203 mm) instead of the original slide valves.

B-15c had higher axle loadings (the highest being the middle axle at 46,200 lb/20,956 kg) and thus a higher adhesion weight of 133,300 lb (60,464 kg).

In an email to Chris Hohl, Frederick "Rick" N.Nowell, III, Archives Chairman and Webmaster of the Boston & Maine Railroad Historical Society gave the following details on the superheated engines in this large class.

Locomotives from first several batches designated B-15 were redesignated B-15-b when superheated: 1360, 1362-1366, 1370-1374, 1376-1377, 1380-1385, 1388, 1391, 1393, 1395, 1397, 1399, 1401, 1402, 1404, 1408, 1415, 1418, 1420, 1421, 1425-1429, 1431, 1435-1438, 1440-1441, 1443-1445, 1448-1451, 1455, 1457, 1458.

B-15a machines were reclassified B-15-c: 1460, 1464-1466, 1468-1470, 1474-1475, 1478, 1481-1485, 1487-1490, 1493-1496, 1498.


Class B-9 (Locobase 11141)

Data from B&M 8 - 1919 Locomotive Classification supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. Works numbers were 933-934 in March 1887, 935-937 in April, and 938 in May.

This was a long-striding Mogul design built by a small, but well-known Massachusetts firm; they were the very last locomotives to emerge from that shop. All six were retained by the Boston & Maine, although the last one was converted to an 0-6-0 switcher with 17" diameter cylinders in 1897.

NB: The direct heating surface (including the firebox heating surface) is an estimate calculated by subtracting the calculated tube heating surface from the reported total evaporative heating surface.

Specifications by Steve Llanso of Sweat House Media
Class161 // B-13a/b/cB-11a/bB-12B-14B-15 syphons
Locobase ID11,140 11,144 11,142 11,143 15,945
RailroadFitchburg (B & M)Fitchburg (B&M)Fitchburg (B & M)Fitchburg (B&M)Boston & Maine (B&M)
CountryUSAUSAUSAUSAUSA
Whyte2-6-02-6-02-6-02-6-02-6-0
Number in Class27554
Road Numbers161 / 239 / 1008-1030, 1036-39250-253/130-133/256-259/1031-1035/1351-13551003-1007 / 1324-13281036-10391405
GaugeStdStdStdStdStd
Number Built27554
BuilderSchenectadyRhode IslandSchenectadySchenectadyB&M
Year18951893189318971918
Valve GearStephensonStephensonStephensonStephensonWalschaert
Locomotive Length and Weight
Driver Wheelbase (ft / m)14 / 4.2715.17 / 4.6214 / 4.2715 / 4.5715 / 4.57
Engine Wheelbase (ft / m)21.67 / 6.6122.92 / 6.9921.67 / 6.6122.75 / 6.9322.75 / 6.93
Ratio of driving wheelbase to overall engine wheebase 0.65 0.66 0.65 0.66 0.66
Overall Wheelbase (engine & tender) (ft / m)47.87 / 14.5947.08 / 14.3556.56 / 17.2449.04 / 14.9549.70 / 15.15
Axle Loading (Maximum Weight per Axle) (lbs / kg)41,434 / 18,794
Weight on Drivers (lbs / kg)114,100 / 51,755109,400 / 49,623110,000 / 49,895117,400 / 53,252124,300 / 56,382
Engine Weight (lbs / kg)131,100 / 59,466128,000 / 58,060128,800 / 58,423140,800 / 63,866143,900 / 65,272
Tender Loaded Weight (lbs / kg)89,00089,000 / 40,37089,000 / 40,37089,000 / 40,370107,600 / 48,807
Total Engine and Tender Weight (lbs / kg)220,100217,000 / 98,430217,800 / 98,793229,800 / 104,236251,500 / 114,079
Tender Water Capacity (gals / ML)4000 / 15.154000 / 15.154000 / 15.154000 / 15.155000 / 18.94
Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT)77 / 6.407 / 6.407 / 6.4010 / 9.10
Minimum weight of rail (calculated) (lb/yd / kg/m)63 / 31.5061 / 30.5061 / 30.5065 / 32.5069 / 34.50
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)63 / 160063 / 160057 / 144863 / 160063 / 1600
Boiler Pressure (psi / kPa)190 / 13.10175 / 12.10160 / 11200 / 13.80200 / 13.80
High Pressure Cylinders (dia x stroke) (in / mm)19" x 26" / 483x66020" x 24" / 508x61019" x 26" / 483x66019" x 26" / 483x66019" x 26" / 483x660
Tractive Effort (lbs / kg)24,061 / 10913.9022,667 / 10281.5922,395 / 10158.2125,327 / 11488.1525,327 / 11488.15
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.74 4.83 4.91 4.64 4.91
Heating Ability
Firebox Area (sq ft / m2)144.42 / 13.42140 / 13.01183.20 / 17.02
Grate Area (sq ft / m2)27.63 / 2.5728 / 2.6030 / 2.7930.20 / 2.8130.20 / 2.81
Evaporative Heating Surface (sq ft / m2)1854 / 172.301662 / 154.461714 / 159.291850 / 171.871857 / 172.52
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)1854 / 172.301662 / 154.461714 / 159.291850 / 171.871857 / 172.52
Evaporative Heating Surface/Cylinder Volume217.30190.45200.89216.83217.65
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation52504900480060406040
Same as above plus superheater percentage52504900480060406040
Same as above but substitute firebox area for grate area27,44028,00036,640
Power L1602462766825
Power MT349.18353.57363.15

Specifications by Steve Llanso of Sweat House Media
ClassB-15/B-15aB-15b/c - superheatedB-9
Locobase ID806 6628 11,141
RailroadBoston & Maine (B&M)Boston & Maine (B&M)Fitchburg (B&M)
CountryUSAUSAUSA
Whyte2-6-02-6-02-6-0
Number in Class140786
Road Numbers1360-14991360-1499119-124/218-223/992-996/1302-1306
GaugeStdStdStd
Number Built1406
BuilderAlcoB&MTaunton
Year190319181887
Valve GearStephensonWalschaertStephenson
Locomotive Length and Weight
Driver Wheelbase (ft / m)15 / 4.5715 / 4.5715.83 / 4.82
Engine Wheelbase (ft / m)22.75 / 6.9322.75 / 6.9324.17 / 7.37
Ratio of driving wheelbase to overall engine wheebase 0.66 0.66 0.65
Overall Wheelbase (engine & tender) (ft / m)51.17 / 15.6051.17 / 15.6045.87 / 13.98
Axle Loading (Maximum Weight per Axle) (lbs / kg)40,934 / 18,56745,900 / 20,820
Weight on Drivers (lbs / kg)127,000 / 57,606128,000 / 58,06092,000 / 41,731
Engine Weight (lbs / kg)145,000 / 65,771150,000 / 68,039103,000 / 46,720
Tender Loaded Weight (lbs / kg)70,890 / 32,15570,890 / 32,15568,800 / 31,207
Total Engine and Tender Weight (lbs / kg)215,890 / 97,926220,890 / 100,194171,800 / 77,927
Tender Water Capacity (gals / ML)5000 / 18.945000 / 18.943600 / 13.64
Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT)10 / 9.1010 / 9.10 6.50 / 5.90
Minimum weight of rail (calculated) (lb/yd / kg/m)71 / 35.5071 / 35.5051 / 25.50
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)63 / 160063 / 160057 / 1448
Boiler Pressure (psi / kPa)200 / 13.80200 / 13.80140 / 9.70
High Pressure Cylinders (dia x stroke) (in / mm)19" x 26" / 483x66019" x 26" / 483x66018" x 24" / 457x610
Tractive Effort (lbs / kg)25,327 / 11488.1525,327 / 11488.1516,234 / 7363.63
Factor of Adhesion (Weight on Drivers/Tractive Effort) 5.01 5.05 5.67
Heating Ability
Firebox Area (sq ft / m2)159.40 / 14.81158 / 14.68123 / 11.43
Grate Area (sq ft / m2)30.20 / 2.8130.30 / 2.8118.50 / 1.72
Evaporative Heating Surface (sq ft / m2)1893 / 175.861446 / 134.341359 / 126.30
Superheating Surface (sq ft / m2)302 / 28.06
Combined Heating Surface (sq ft / m2)1893 / 175.861748 / 162.401359 / 126.30
Evaporative Heating Surface/Cylinder Volume221.87169.48192.26
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation604060602590
Same as above plus superheater percentage604070902590
Same as above but substitute firebox area for grate area31,88036,97217,220
Power L1662112,1933714
Power MT344.81630.02267.00

Reference