Baltimore & Ohio 2-8-8-0 "Consolidation Mallet" Type Locomotives

Class EL-1, -2, -3, -5 (Locobase 439)

Alvin F Staufer & Lawrence W Sagle, B & O Power (1964).

B&O compound Mallets designed to negotiate curves as sharp as 22 deg. Total weight distribution varied by only 1,100 lb between the front and rear engine units.

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 by Baldwin. All surviving locomotives were converted from 1927 on after the prototype demonstrated a considerable improvement in pulling power. The last of these left service in 1954.

Class EL-3a (Locobase 305)

B&O rebuilds of B&O compound Mallets to 4-cylinder simple-expansion machines beginning in 1927. 64 engines were converted altogether, all to the same powerful standard. Compared to the EL-6a conversion, these locomotives didn't work quite so hard, but steamed as easily. Smaller drivers undoubtedly confined them to hill work, where they served until the early 1950s.

Class EL-6a (Locobase 3556)

These were simpled conversions of SAL 2-8-8-2s that had come onto the B&O in 1922. They had a relatively high driver diameter and a hard-worked, but relatively free-steaming boiler. The last of these left service in 1954.

Wiener (1930) for data.

Specifications
Class	EL-1, -2, -3, -5	EL-3a	EL-6a
Locobase ID	439	305	3556
Railroad	Baltimore & Ohio (B&O)	Baltimore & Ohio (B&O)	Baltimore & Ohio (B&O)
Whyte	2-8-8-0	2-8-8-0	2-8-8-0
Road Numbers	7100+	7150	7300-7315
Gauge	Std	Std	Std
Builder	Baldwin	B & O	B & O
Year	1916	1927	1920
Valve Gear	Walschaert		Walschaert
	Locomotive Length and Weight
Driver Wheelbase	15.50'	15.50'	15.46'
Engine Wheelbase	50.33'	50.33'	53.33'
Ratio of driving wheelbase to overall engine wheebase	0.31	0.31	0.29
Overall Wheelbase (engine & tender)	82.61'	82.61'	98.27'
Axle Loading (Maximum Weight per Axle)		58000 lbs
Weight on Drivers	462500 lbs	459400 lbs	456700 lbs
Engine Weight	485600 lbs	484400 lbs	492000 lbs
Tender Light Weight	206400 lbs	262000 lbs	219000 lbs
Total Engine and Tender Weight	692000 lbs	746400 lbs	711000 lbs
Tender Water Capacity	12000 gals	18000 gals	12000 gals
Tender Fuel Capacity (oil/coal)	20 tons	18 tons	20 tons
Minimum weight per yard of rail on which locomotive could run	96.35 lb rail	95.71 lb rail	95.15 lb rail
	Geometry Relating to Tractive Effort
Driver Diameter	58"	58"	63"
Boiler Pressure	210 psi	210 psi	225 psi
Cylinders (dia x stroke)	26" x 31"	24" x 32" (4)	25" x 32" (4)
Low Pressure Cylinders (dia x stroke)	41" x 31"	" x "	" x "
Tractive Effort	91993 lbs	113452 lbs	121429 lbs
Factor of Adhesion (Weight on Drivers/Tractive Effort)	5.03	4.05	3.76
	Heating Ability
Firebox Area	393 sq. ft	341 sq. ft	398 sq. ft
Grate Area	88.17 sq. ft	88.17 sq. ft	88 sq. ft
Evaporative Heating Surface	5836	5784	5922
Superheating Surface	1415	1415	1380
Combined Heating Surface	7251	7199	7302
Evaporative Heating Surface/Cylinder Volume	306.36	172.60	162.87
	Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation	18515.70	18515.70	19800
Same as above plus superheater percentage	22128.96	22155.05	23541.99
Same as above but substitute firebox area for grate area	98635.36	85685.31	106473.99
Power L1	8800.48	12251.37	13210.39
Power MT	335.60	470.35	510.16