Maryland & Pennsylvania 2-8-0 "Consolidation" Locomotives in the USA


Class Details by Steve Llanso of Sweat House Media

Class 23 (Locobase 6024)

Data from George W. Fitch, Jr.'s compilation (Maryland and Pennsylvania Railroad Preservation and Historical Society photocopy reprint, 2004) and "Steam Locomotives of the Maryland & Pennsylvania Railroad" on the Maryland & Pennsylvania Railroad website, last accessed 12 March 2017 at http://www.maparailroadhist.org/locos.htm . See also DeGolyer, Volume 24, p. 163; Volume 25, p. 229; Volume 47, pp. 214+; and MA&PA 1925 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

Evidence that the Ma & Pa was serious about its freight hauling came with this class of Consolidations supplied over a decade (1902 - works #20003-20004, 1905 - 25426, and 1912 - 38697). Southern valve gear replaced the inside link motion in 23 (September 1915) and 23 received Brown power reverse gear in February 1917. 24 received both updates in June 1916.

25's last service day was 13 November 1932; seven years later the 25 was sold for scrap in November 1939. 24 had been sold for scrap in May 1935. 23 and 26 continued in service until March 1947.


Class 41 (Locobase 6025)

Locomotive data from George W. Fitch, Jr.'s compilation (Maryland and Pennsylvania Railroad Preservation and Historical Society photocopy reprint, 2004) and DeGolyer, Volume 50, pp. 245+. Works numbers were 41504-41505 in June 1914.

The first superheated locomotives for the Ma & Pa, this pair represented a substantial step up in power. Arch tubes contributed 28.3 sq ft (2.63 sq m) of the firebox heating surface and the piston valves had relatively large 14" (356 mm) diameters. They traveled on 70 lb/yard (35 kg/metre) rails.

42 was retired first in January 1952. 41 held on for another five years before being scrapped in May 1957.

Locobase note: Seven years later, Railway Age profiled a batch of eleven Mexican Railway locomotives (Locobase 3236) with exactly the same specifications. The data come from very different yet equally (and solidly) reliable sources, so this may an example of selling from stock.


Class 43 (Locobase 6026)

Locomotive data from George W. Fitch, Jr.'s compilation (Maryland and Pennsylvania Railroad Preservation and Historical Society photocopy reprint, 2004). See also DeGolyer, Volume 76, pp. 360+. Works number was 58491 in June 1925.

The last new locomotive for the Ma & Pa, this Consolidation had the same tractive power as the 1914 pair (Locobase 6025), but was heavier and had a higher percentage of superheat area. Arch tubes in the firebox of the 1914 engines were replaced in 43's design by two thermic syphons that supported the firebox's brick arch, which represented 50.5 sq ft (4.69 sq m) of firebox heating surface. 43 also had 14" (356 mm) diameter pistons. The design can be described as typical of late-period American 2-8-0s, although the syphons were relatively rare as was the Elesco feed water heater.

Data from M&PA 1956ca Locomotive Diagrams, supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange, shows that the 43 went out of service in December 1956.

Principal Dimensions by Steve Llanso of Sweat House Media
Class234143
Locobase ID6024 6025 6026
RailroadMaryland & Pennsylvania (Ma & Pa)Maryland & Pennsylvania (Ma & Pa)Maryland & Pennsylvania (Ma & Pa)
CountryUSAUSAUSA
Whyte2-8-02-8-02-8-0
Number in Class421
Road Numbers23-2641-4243
GaugeStdStdStd
Number Built421
BuilderBurnham, Williams & CoBaldwinBaldwin
Year190219141925
Valve GearStephensonWalschaertWalschaert
Locomotive Length and Weight
Driver Wheelbase (ft / m)14 / 4.2714.25 / 4.3414.25 / 4.34
Engine Wheelbase (ft / m)21.67 / 6.6123.33 / 7.1123.33 / 7.11
Ratio of driving wheelbase to overall engine wheebase 0.65 0.61 0.61
Overall Wheelbase (engine & tender) (ft / m)46.63 / 14.2155.21 / 16.8355.62 / 16.95
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)108,550 / 49,238170,330 / 77,260182,180 / 82,636
Engine Weight (lbs / kg)123,600 / 56,064193,850 / 87,929207,050 / 93,916
Tender Loaded Weight (lbs / kg)89,253 / 40,485122,680 / 55,647123,800 / 56,155
Total Engine and Tender Weight (lbs / kg)212,853 / 96,549316,530 / 143,576330,850 / 150,071
Tender Water Capacity (gals / ML)4000 / 15.156000 / 22.736000 / 22.73
Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT)8 / 7.3010 / 9.1010 / 9.10
Minimum weight of rail (calculated) (lb/yd / kg/m)45 / 22.5071 / 35.5076 / 38
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)50 / 127051 / 129551 / 1295
Boiler Pressure (psi / kPa)175 / 12.10190 / 13.10190 / 13.10
High Pressure Cylinders (dia x stroke) (in / mm)19" x 24" / 483x61022" x 28" / 559x71122" x 28" / 559x711
Tractive Effort (lbs / kg)25,775 / 11691.3642,915 / 19465.9442,915 / 19465.94
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.21 3.97 4.25
Heating Ability
Firebox Area (sq ft / m2)130.30 / 9.60207.30 / 19.27227.50 / 21.14
Grate Area (sq ft / m2)30.70 / 2.8549.50 / 4.6049.70 / 4.62
Evaporative Heating Surface (sq ft / m2)1555 / 144.522425 / 225.372331 / 216.64
Superheating Surface (sq ft / m2)511 / 47.49587 / 54.55
Combined Heating Surface (sq ft / m2)1555 / 144.522936 / 272.862918 / 271.19
Evaporative Heating Surface/Cylinder Volume197.44196.85189.22
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation537394059443
Same as above plus superheater percentage537311,00411,332
Same as above but substitute firebox area for grate area22,80346,08351,870
Power L1408610,56711,473
Power MT331.94547.08555.35