Baltimore & Ohio Other Articulated Locomotives in the USA

Class KL-1 (Locobase 13790)

Data from DeGolyer, Volume 38, p. 161. (Thanks to Chris Hohl for supplying the road number.)

In 1911, the B & O ordered a special 2-6-8-0 by mating one of its E-24 Consolidations (Locobase 4786) to a new front boiler and engine set that contained a feedwater heater with 369 2" tubes of much shorter length (8 feet 3 inches) and a total heating service area of 1,594 sq ft. The LP cylinders under this boiler section had 34" diameters.

The same problems with slipping and uneven traction encountered by other users of the 2-6-8-0 arrangement led to no other such engines and the KL-1 was converted back to a 2-8-0 in 1917.

Class LL-1 (Locobase 9617)

Data from B & O to 1954 Asstd Loco Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. See also "Mallet Locomotive with Superheater 0-8-8-0 Type - Baltimore & Ohio Railroad", American Engineer and Railroad Journal, Volume 85, No 5 (May 1911), pp. 183-184; and Roy V Wright (ed), Locomotive Dictionary, 1912 (3rd Edition) (New York: Simmons-Boardman Publishing Company, 1912), p. 187. (Thanks to Chris Hohl for his 5 May 2017 email supplying the 1912 tender capacities and weight.) Works numbers were 49212-49216, 49699-49703 in March 1911; 50442-50451 in January 1912; 53748-53757 in August 1913.

A two-batch class of pushers that varied primarily in their weights. The first batch -- 7020-7039 -- put 461,000 lb (209,106 kg) on the rail while the last ten weighed five tons more. Chris Hohl's review of the 1912 Locomotive Dictionary yielded a tender whose water capacity was 9,200 US gallons (34,882 litres) and coal capacity 16 tons (14.5 metric tons). It weighed 181,500 lb (82,327 kg). The original count of tubes and flues was 277 and 38, later rearranged to the 273 tubes and 40 flues shown in the specs above.

Delivered with slide valves actuated by Walschaert gear feeding the low-pressure cylinders, some of the engines later received piston valves on those big cans. These were actuated by Baker gear, while the rear HP cylinders still used the Walschaert gear.

Boiler pressure settings varied considerably over the years. B&O diagrams show the following settings, resulting tractive effort, and factors of adhesion:

BP/Bar Tractive effort Factor of Adhesion

210/14.5 105,000 lb/47,627 kg 4.6

225/15.5 112,400 lb/50,984 kg 4.18

240/ 16.55 119,980 lb/54,422 kg 4.0

215/14.83 107,400 lb/ 48,716 kg 4.39

Given the order in the table,

According to Drury (1993), these big engines proved "slow and complicated". Several were rebuilt as EL-4 class 2-8-8-0s (see Locobase 16285).

Still, eleven LL-1 remained on the roster as of 1941 and served throughout World War Two before being scrapped in 1949-1950. These most likely had their boiler pressures set to 215 psi.

Class O/DD1 (Locobase 2794)

Data from "Mallet Articulated Compound for the B&O", Railway and Locomotive Engineering, Volume 17, No 6 (June 1904), pp. 283-284. (Thanks to Chris Hohl for his 20 May 2017 email reporting the original tender weight and capacity.) Works number was 27478 in May 1904.

The first standard-gauge Mallet built in the United States, this helper engine was jointly designed by the B&O's James E Muhlfield and Alco's Carl J. Mellin. Old Maud, so called after a comic-strip mule, proved an immediate success on the B&O's western Pennsylvania grades. Her HP cylinders were served by 10" (254 mm) piston valves; LP cylinders

Her scrapping came only in 1938.