Class EL-1, EL-2, EL-3, EL-5 (Locobase 439)
Alvin F Staufer & Lawrence W Sagle, B & O Power (1964). Data from Record of Recent Construction #91 (Baldwin Locomotive Works, 1918), p.32-33. See also DeGolyer, Volume 55, pp. 389+ and Volume 58,; and "Mallet Articularted Locomotives for the Baltimore & Oho RR" , Railway Review, Volume 59, No.2 (8 July 1916), pp. 50-51. (Thanks to Chris Hohl for his 28 April 2019 email correcting the cylinder stroke length and the Alco order.)
Baldwin works numbers were:
EL-1
1916
January 42832; February 42854-42855; March 43047-43049, 43071-43073; April 43140, 43148-43150, 43275; May 43289
EL-3
1917
July 45989; August 46112, 46164; September 46267, 46406; October 46677, 46713; December 47282, 47391, 47489
1918
January 47650; February 47746, 47852, 47950; March 48026, 48067, 48130, 48194; April
48277-48279; May 48577, 48682; June 48901, 48902, 48940, 49086-49087; July 49308, 49400; August 49545
EL-5
1919
September 52371, 52425; November 52464-52468, 52518-52520, 52552-2555, 52598-52605; December 52642-52645
Alco's Schenectady Works produced fifteen to the same design:
EL-2
1916
55664-55678 in April 1916
Baldwin reported that these huge locomotives were intended for the 2.4% grades in the Cumberland Division, over which they would haul long, loaded trains of coal cars. Substantially bigger than the Alcos shown as LL-1s 0-8-8-0s in Locobase 9617 and 2-8-8-0s in Locobase 16285, these engines disposed 41% more superheater area and increased combustion chamber length by 22" (559 mm).
The cylinders used a combination of 14" (356 mm) piston valves for the HP cylinders actuated by Baker gear and Allen balanced slide valves for the LP cylinders operated by Walschaert's gear. (Thanks to Chris Hohl for providing an example of the weird-looking result.) When the LP cylinders were rebuilt with piston valves, they were opened by Baker gear.. Hohl later pointed out that the EL-5s compounds were delivered with Baker gear actuating all four valves. He also noted that the Baldwin spec called for 25 3/4" diameter HP, and 40 3/4" diameter LP cylinders. But the B&O's diagrams show EL-5s fitted with the 26/41" cylinders fitted to the other subclasses.
Combustion chamber area of 113 sq ft (10.50 sq m) and five arch tubes offering 35 sq ft (3.25 sq m) supplemented the firebox heating surface area. Front engine equalization was split between the front two driver sets and the rear two driver sets. Rear engine equalization worked continuously.
Definitely intended for main-line service, these big articulateds were able to negotiate curves as sharp as 22 deg. Total weight distribution varied by only 1,100 lb between the front and rear engine units. Each locomotive trailed a Vanderbilt cylindrical tender.
Several classes beginning with 15 EL-1 (1916) and followed by 15 EL-2 (7200-7214 in 1916), 30 EL-3 (7115-7144 in 1917) and 26 EL-5 (7145-7170 in 1919-1920). All were Baldwin engines except the 15 EL-2s, which came from Alco's Schenectady Works.
64 of the total converted to four-cylinder simple-expansion engines from 1927 on after the prototype demonstrated a considerable improvement in pulling power; see Locobase 305.
The last of these left service in 1954.
Class EL-1a, -2a, -3a, -5a (Locobase 305)
Data from tables in 1930 Locomotive Cyclopedia; and B&O Assorted Steam Locomotive Diagrams supplied in August 2013 by Allen Stanley from his extensive Rail Data Exchange collection. (Thanks to Eric Botts for his 6 May 2021 email supplying the correct information about the sub-classes rebuilt to the simple-expansion system.)
These were B&O rebuilds of B&O compound Mallets (Locobase 439) to four-cylinder simple-expansion machines beginning in 1927. Compared to the EL-6a conversion (Locobase 3556), these locomotives didn't work quite so hard, but steamed as easily. All four cylinders used 14" (356 mm) piston valves.
64 engines were converted altogether, all to the same powerful standard. The roster of simpled locomotives consisted of:
EL-1
7100, 7102-7110, 7112-7113
EL-2
7200, 7204, 7206, 7208-7210, 7213-7214
EL-3
7115, 7117, 7119-7121, 7125, 7127, 7129, 7131-7135, 7137, 7139-7144
EL-5
7145-7147, 7149-7162, 7164-7170
Smaller drivers undoubtedly confined them to hill work, where they served until the early 1950s.
Class EL-4 (Locobase 16285)
Data from B & O to 1954 Asstd Loco Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.
Locobase 9617 shows the original LL-1 0-8-8-0 class as delivered in 1911-1912.
According to Drury (1993), these big engines proved "slow and complicated". Several were rebuilt as EL-4 class 2-8-8-0s simply by adding a leading truck. A B&O Locomotive Roster dated 1 January 1934 shows only eight converted to that arrangement; the other 22 were still classed as LL-1. The 1946 roster shows that one more LL-1 (7039) was converted during the war years. The 7041 and 7049, originally delivered in 1913, had engine weighst of 482,500 lb (218,859 kg) each.
Still, all nine served throughout World War Two before being scrapped in 1949-1950.
