B&O's EM-1 class was known as the Yellowstone design, which were
first put into service on the Northern Pacific in 1928. The NP wanted a
powerful articulated (meaning that either one, or both sets of the
locomotive's driving wheels pivots to better and more safely negotiate
curves) that could not only move heavy freights through the Northern
Plains of the Dakotas but also at relatively quickly. Ultimately,
however, only two other lines aside from the B&O (which as the last
to buy the 2-8-8-4) purchased Yellowstones; the Missabe Road (DM&IR)
acquired 18 (Class M-3/M-4) in 1941 to pull heavy ore trains and
Southern Pacific picked up 12 in 1939 (Class AC-9).
The EM-1 was developed during the very end of the steam era and accordingly would carry the latest technology available. Thirty of these locomotives would be built, all coming from the Baldwin Locomotive Works, and were delivered to the B&O towards the end of World War II between 1944 and 1945. The eastern trunk line was one of the first to embrace diesel technology purchasing a boxcab switcher from Alco and Ingersoll-Rand in 1924 and then testing Electro-Motive's streamlined EA in 1935. The railroad desperately wished to continue purchasing diesels (then EMC's FT model) to keep up with wartime traffic. However, with restrictions in place the B&O was forced to settle buying more steam, settling on the Yellowstone design.
The EM-1s had a rather low boiler pressure comparative to other models
in its class but this low pressure had a great benefit, a high factor
of adhesion (4.22). This high ratio allowed the locomotive to start
rather efficiently in that it was not as susceptible to wheel slippage
as other designs. For instance, this added incentive was an extra
benefit in the type of service the B&O originally designated the
EM-1, the torturous grades of the railroad’s West End (its Cumberland
and Pittsburgh Divisions), through the Appalachians. The locomotive did
a marvelous job, having little trouble hauling merchandise
or coal drags over the steep climbs of Cranberry Grade, along the West
Virginia/Maryland border, or over Sand Patch in Pennsylvania.
In time, the railroad actually became rather fond of its
2-8-8-4s. The EM-1 was a true sight to behold if one was lucky enough
to witness it trackside at work. A classic example is the locomotive working upgrade over Sand Patch. The engine
exemplified what made the steam locomotive such an admired and
respected machine, even outside the railroad and railfan community. The
pure power and deafening sound by a locomotive of the EM-1’s size is
perhaps something words, pictures and maybe even videos can never truly
replicate without the fortune of being there in person to witness such
for yourself. While the size of the EM-1 is enough in itself to instill
awe, seeing it in person illustrates the point that much more. The below specifications of the locomotive are courtesy of John Patton.
Baltimore & Ohio Class EM-1
Builder: Baldwin Locomotive Works
Cylinders: Diameter x Stroke (4) - 24" x 32"
Driver diameter: 64 Feet Boiler pressure: 235 PSI Grate Area: 117.5 Feet
Weight on drivers: 485,000 Pounds
Total engine weight: 628,700 Pounds
According to John Patton, "the EM-1s were said to be easy
steamers to operate and crews liked them. With minor stay bolt trouble
they were perfect for the B&O in every way possible. As said upon
delivery by head of machinery, they had everything, all wheels had
roller bearings and were top of the line for steam on the
B&O...these B&O articulateds were 1,010,700 pounds, laden;
carried 22,000 gallons of water and 25 tons of coal."
The EM-1 would be short-lived, however. By the late 1950s the
locomotives had been renumbered to make room for new diesels that the
B&O could finally purchase after the war had ended, and the EM-1 was
shifted from the mountain regions to the Ohio River and the railroad’s
Pittsburgh Division. This time period also spelled the end for steam
itself throughout the nation’s railroads. After less than twenty years
of service (in steam locomotive years this is very young) the final EM-1
was dropped from the roster around 1960. However, according to Mr.
Patton, "the last one off the roster was to be saved for the B&O
Museum in Baltimore, but it never happened due to lack of funding and the
museum not being open to try an reserve funding for such." Unfortunately for both railfan and historian alike, not one EM-1 is preserved for future generations to tour and see.
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Baltimore & Ohio
Class EM-1 2-8-8-4