2-8-8-4
Encyclopedia
Whyte notation
The Whyte notation for classifying steam locomotives by wheel arrangement was devised by Frederick Methvan Whyte and came into use in the early twentieth century encouraged by an editorial in American Engineer and Railroad Journal...
for the classification of steam locomotive
Steam locomotive
A steam locomotive is a railway locomotive that produces its power through a steam engine. These locomotives are fueled by burning some combustible material, usually coal, wood or oil, to produce steam in a boiler, which drives the steam engine...
s, a 2-8-8-4 is a steam locomotive with two leading wheel
Leading wheel
The leading wheel or leading axle of a steam locomotive is an unpowered wheel or axle located in front of the driving wheels. The axle or axles of the leading wheels are normally located in a truck...
s, two sets of eight driving wheel
Driving wheel
On a steam locomotive, a driving wheel is a powered wheel which is driven by the locomotive's pistons...
s, and a four-wheel trailing truck.
Other equivalent classifications are:
- UIC classificationUIC classificationThe UIC classification of locomotive axle arrangements describes the wheel arrangement of locomotives, multiple units and trams. It is set out in the International Union of Railways "Leaflet 650 - Standard designation of axle arrangement on locomotives and multiple-unit sets". It is used in much...
: 1DD2 (also known as German classification and Italian classification) - French classification: 140+042
- Turkish classificationTurkish classificationIn the Turkish classification system for railway locomotives, the number of powered axles are followed by the total number of axles. It is identical to the Swiss system except that the latter places a slash between the two numbers.Thus0-6-0 becomes 33...
: 45+46 - Swiss classification: 4/5+4/6
- Russian classification: 1-4-0+0-4-2
The equivalent UIC classification is, refined for Mallet locomotives, (1′D)D2′.
Such a long locomotive must be an articulated locomotive
Articulated locomotive
Articulated locomotive usually means a steam locomotive with one or more engine units which can move independent of the main frame. This is done to allow a longer locomotive to negotiate tighter curves...
, and all the examples produced were of the Mallet type, having a hinged joint between the first and second groups of driving wheels, and having the superstructure of the locomotive rigidly attached to the rearmost set, with the forward set and leading truck allowed to swing laterally on curves.
The type was generally named the Yellowstone, a name given it by the first owner, the Northern Pacific Railway
Northern Pacific Railway
The Northern Pacific Railway was a railway that operated in the west along the Canadian border of the United States. Construction began in 1870 and the main line opened all the way from the Great Lakes to the Pacific when former president Ulysses S. Grant drove in the final "golden spike" in...
, whose lines run near Yellowstone National Park
Yellowstone National Park
Yellowstone National Park, established by the U.S. Congress and signed into law by President Ulysses S. Grant on March 1, 1872, is a national park located primarily in the U.S. state of Wyoming, although it also extends into Montana and Idaho...
. Seventy-two Yellowstone type locomotives were built for four different US railroads.
The 2-8-8-4 was the common choice of arrangement for the very largest steam locomotives at moderate speeds. All classes of Yellowstone had fairly small drivers of 63 to 64 in (1.6 to 1.6 m). For greater speeds, the Union Pacific Railroad
Union Pacific Railroad
The Union Pacific Railroad , headquartered in Omaha, Nebraska, is the largest railroad network in the United States. James R. Young is president, CEO and Chairman....
chose a four-wheel leading truck and 68 inches (1.7 m) drivers for its Big Boy
Union Pacific Big Boy
Big Boy was the name of the Union Pacific Railroad's 4000-class 4-8-8-4 articulated steam locomotives, built between 1941 and 1944 by American Locomotive Company...
4-8-8-4
4-8-8-4
In the Whyte notation for the classification of steam locomotives by wheel arrangement, a 4-8-8-4 is a locomotive with a four-wheel leading truck, two sets of eight driving wheels, and a four-wheel trailing truck.Other equivalent classifications are:...
class.
Several classes of Yellowstone, especially the Duluth, Missabe and Iron Range's locomotives, are among the largest steam locomotives, with the exact ranking dependent on the criteria used.
Northern Pacific
The Northern Pacific RailwayNorthern Pacific Railway
The Northern Pacific Railway was a railway that operated in the west along the Canadian border of the United States. Construction began in 1870 and the main line opened all the way from the Great Lakes to the Pacific when former president Ulysses S. Grant drove in the final "golden spike" in...
was the first railroad to order a 2-8-8-4. The first was built in 1928 by ALCO
American Locomotive Company
The American Locomotive Company, often shortened to ALCO or Alco , was a builder of railroad locomotives in the United States.-Early history:...
; at the time, it was the largest locomotive ever built, and it was equipped with the largest firebox ever applied to a steam locomotive, some 182 ft2 in area. The purpose of this was to burn Rosebud coal, a very low-quality coal the NP could obtain very cheaply on-line. Unfortunately, that firebed was too large for the available draft, and the fire burned poorly. The problem was mitigated by blocking off the first few feet of the grates. Baldwin
Baldwin Locomotive Works
The Baldwin Locomotive Works was an American builder of railroad locomotives. It was located in Philadelphia, Pennsylvania, originally, and later in nearby Eddystone, Pennsylvania. Although the company was very successful as a producer of steam locomotives, its transition to the production of...
built eleven more for the NP in 1930.
Southern Pacific
The Southern Pacific Railroad'sSouthern Pacific Railroad
The Southern Pacific Transportation Company , earlier Southern Pacific Railroad and Southern Pacific Company, and usually simply called the Southern Pacific or Espee, was an American railroad....
famous "cab-forward
Cab forward
The term cab forward refers to various rail and road vehicle designs which place the driver's compartment substantially farther towards the front than is common practice.- Rail locomotives :...
" articulated steam locomotives were effectively a Yellowstone in reverse, but the SP also owned some conventional 2-8-8-4s for use on its less mountainous routes. Twelve AC-9 class locomotives
Southern Pacific class AC-9
The AC-9 was one of two Southern Pacific Railroad'sarticulated steam locomotive class that ran smokebox forward after 1920. Twelve AC-9 class locomotives were built by Lima in 1939 and were Southern Pacific's biggest steam engines...
were built by Lima
Lima Locomotive Works
Lima Locomotive Works was an American firm that manufactured railroad locomotives from the 1870s through the 1950s. The company took the most distinctive part of its name from its main shops location in Lima, Ohio. The shops were located between the Baltimore & Ohio's Cincinnati-Toledo main line...
in 1939; and featured skyline casings with striped pilot
Pilot (locomotive)
In railroading, the pilot is the device mounted at the front of a locomotive to deflect obstacles from the track that might otherwise derail the train. In some countries it is also called cowcatcher or cattle catcher....
s. Originally built to burn coal, they were later converted to oil firing.
Duluth, Missabe and Iron Range
The Duluth, Missabe and Iron Range RailwayDuluth, Missabe and Iron Range Railway
The Duluth, Missabe and Iron Range Railway is a railroad operating in northern Minnesota and Wisconsin that hauls iron ore and later taconite to the Great Lakes ports of Duluth and Two Harbors, Minnesota...
was an iron ore hauling railroad in Minnesota
Minnesota
Minnesota is a U.S. state located in the Midwestern United States. The twelfth largest state of the U.S., it is the twenty-first most populous, with 5.3 million residents. Minnesota was carved out of the eastern half of the Minnesota Territory and admitted to the Union as the thirty-second state...
. Iron ore is a heavy commodity and the DM&IR operated long trains of ore cars, requiring as much power as the railroad could get their hands on. The design of these locomotives was based upon a series of 10 powerful 2-8-8-2
2-8-8-2
.A 2-8-8-2, in the Whyte notation for describing steam locomotive wheel arrangements, is an articulated locomotive with a two-wheel leading truck, two sets of eight driving wheels, and a two-wheel trailing truck. The equivalent UIC classification is, refined to Mallet locomotives, D1...
s that Baldwin had built previously for the Western Pacific Railroad
Western Pacific Railroad
The Western Pacific Railroad was a Class I railroad in the United States. It was formed in 1903 as an attempt to break the near-monopoly the Southern Pacific Railroad had on rail service into northern California...
. The need for a larger, coal burning firebox and a longer, all-weather cab led to the use of a four-wheel trailing truck, giving them the "Yellowstone" wheel arrangement. They were the most powerful Yellowstones built, producing 140000 lbf (622.8 kN) of tractive effort
Tractive effort
As used in mechanical engineering, the term tractive force is the pulling or pushing force exerted by a vehicle on another vehicle or object. The term tractive effort is synonymous with tractive force, and is often used in railway engineering to describe the pulling or pushing capability of a...
, and had the most weight on drivers so that they were not prone to slipping as were other Yellowstones.
Eight locomotives (class M-3) were built by Baldwin in 1941. The Yellowstones met or exceeded the DM&IR specifications so ten more were ordered (class M-4). The second batch was completed late in 1943 after the Missabe's seasonal downturn in ore traffic, so some of the new M-4s were leased to and delivered directly to the Denver & Rio Grande Western.
The next winter, the D&RGW again leased the DM&IR's Yellowstones as helpers
Bank engine
A bank engine or helper engine or pusher engine is a railway locomotive that temporarily assists a train that requires additional power or traction to climb a grade...
over Tennessee Pass, Colorado
Tennessee Pass (Colorado)
Tennessee Pass elevation is a high mountain pass in the Rocky Mountains of central Colorado in the United States.The pass traverses the continental divide north of Leadville in a gap between the northern end of the Sawatch Range to the west and the northern end of the Mosquito Range to the east...
and for other mainline freight duties. The Rio Grande returned the Yellowstones after air-brake failure caused Number 224 to wreck on the Fireclay Loop. This was despite the Rio Grande's earlier assessment that these Yellowstones were the finest engines to ever operate on the railroad.
DM&IR's locomotives were the only Yellowstones equipped with a high-capacity pedestal or centipede tender, and had roller bearings on all axles. Some of the locomotives were fitted with the cylindrical Elesco feedwater heater
Feedwater heater
A feedwater heater is a power plant component used to pre-heat water delivered to a steam generating boiler. Preheating the feedwater reduces the irreversibilities involved in steam generation and therefore improves the thermodynamic efficiency of the system...
before the smoke stack
Chimney
A chimney is a structure for venting hot flue gases or smoke from a boiler, stove, furnace or fireplace to the outside atmosphere. Chimneys are typically vertical, or as near as possible to vertical, to ensure that the gases flow smoothly, drawing air into the combustion in what is known as the...
, while others used a Worthington unit with its rectangular box in the same location.
Only one Yellowstone was retired before dieselization took place on the Missabe; Number 237 was sold for scrap after it was involved in a wreck. The rest of the 2-8-8-4s were retired between 1958 and 1963 as diesel locomotives completely took over on the Missabe Road.
Three of the eighteen built still survive and are on display Number 227 at the Lake Superior Railroad Museum
Lake Superior Railroad Museum
The Lake Superior Railroad Museum is a railroad museum in Duluth, Minnesota.The museum has seven steam, fourteen diesel and two electric locomotives, and over 40 other pieces of rolling stock...
in Duluth, Minnesota
Duluth, Minnesota
Duluth is a port city in the U.S. state of Minnesota and is the county seat of Saint Louis County. The fourth largest city in Minnesota, Duluth had a total population of 86,265 in the 2010 census. Duluth is also the second largest city that is located on Lake Superior after Thunder Bay, Ontario,...
, Number 225 in Proctor, Minnesota
Proctor, Minnesota
As of the census of 2000, there were 2,852 people, 1,196 households, and 772 families residing in the city. The population density was 942.8 people per square mile . There were 1,246 housing units at an average density of 411.9 per square mile...
, and Number 229 in Two Harbors, Minnesota
Two Harbors, Minnesota
As of the census of 2000, there were 3,613 people, 1,636 households, and 953 families residing in the city. The population density was 1,120.7 people per square mile . There were 1,631 housing units at an average density of 505.9 per square mile...
.
Baltimore and Ohio
When the U.S. became involved in World War II, The American railroads saw dramatic increases in rail traffic demands for freight and passenger trains from hauling troops to supplies for the military. The Baltimore and Ohio RailroadBaltimore and Ohio Railroad
The Baltimore and Ohio Railroad was one of the oldest railroads in the United States and the first common carrier railroad. It came into being mostly because the city of Baltimore wanted to compete with the newly constructed Erie Canal and another canal being proposed by Pennsylvania, which...
along with other railroads wanted to purchase more of the diesel
Diesel locomotive
A diesel locomotive is a type of railroad locomotive in which the prime mover is a diesel engine, a reciprocating engine operating on the Diesel cycle as invented by Dr. Rudolf Diesel...
locomotives for use since they were showing improved performance over steam-powered locomotives to meet the war time demands. But the War Production Board regulated locomotive design by prohibiting production of new locomotives to proven designs used before U.S. war involvement and all new designs were ordered as shelved until the war emergency was over. So along with producing 40 new Class T-3 4-8-2 type locomotives in-house at their Mt. Claire shops in Baltimore, MD, The B&O took delivery of 30 Class EM-1
Baltimore and Ohio Railroad locomotives
On the Baltimore and Ohio Railroad, locomotives were always considered of great importance, and the railroad was involved in many experiments and innovations.-Early locomotives:...
Yellowstones in 1944 and 1945, the largest number and the smallest of this type built by Baldwin as well as being the most modern.
The EM-1 produced 115000 pound-forces (511.5 kN) of tractive effort on 64 inches (1.6 m) drivers with 235 pound per square inches (1.6 MPa) steam pressure, and four 24 by cylinders. The tender carried 22000 gallons (83.3 m³) of water and 25 tons of coal. The engine weighed in at 627000 pounds (284.4 t) while the tender weighed 328000 pounds (148.8 t) for a combined 1010700 pounds (458.4 t). Nothing bigger could operate within the operating tunnel clearances and track restrictions on the B&O's Main Line.
They were equipped with all the newest technology including the Worthington Feedwater Heater, Superheater with front-end throttle, Cyclone Front End, thermic syphons, a lateral cushioning device in the front pair of drivers, both engines and the front wheels the trailing truck, as well as roller bearings on all axles, engine and tender, which gave them the reputation of "yard creepers," because three men could move one on a level track with the cylinder cocks open.
B&O President Roy B. White, after inspecting the first one delivered, said to the General Superintendent of Motive Power and Equipment A.K. Galloway, "Well, I must say, they have everything!"
7600–7619 were built and delivered in 1944 and 7620–7629 in 1945, all by the Baldwin Locomotive Works of Philadelphia, PA. They were promptly put to work on the Cumberland Division, especially the rugged West End subdivision with its more than 2% grades and tight curves where they performed magnificently with the elder 2-8-8-0 EL classes hauling Northern West Virginia coal and freights. Since the EM-1s were equipped with the roller bearings throughout, they also handled mail and express trains, replacing two of the B&O's class T-3 4-8-2 Mountains. That practice continued until January 21, 1947, when near Oakland, MD, express train 29 with engine 7625 derailed with the locomotive rolling onto the engineer's side, killing the engineer. As a result, the EM-1's were restricted to coal and freight trains only until the late 1950's when the B&O used EM-1 #7600 for various railfan trips.
The EM-1's were also used on the Pittsburgh Division over Sand Patch Grade near Meyersdale, PA with either empty hoppers or ones loaded with iron ore or dolomite westbound, coal eastbound, as well as freight trains in both directions. In the late 1950's, the B&O used EM-1 #7600 for railfan trips mostly between Cumberland, MD and Connellsville, PA. Well-known Photographer and Cumberland, MD native William P. Price captured on still pictures and 8mm films, the EM-1's on the eastern side of Sand Patch pulling heavy trains with two of the B&O's 2-10-2 Class S1 and S1a "Big Sixes" on the rear as helpers dispatched from Hyndman, PA.
Near the end of steam, they were all sent out to Fairmont and Wheeling, West Virginia, and Lorain, Ohio, with lake-bound coal trains as well as runs between Willard, OH and Garrett, IN until the B&O started to retire them from 1957 to 1960. As good as they were, they still could not compete with the diesels. Unfortunately, none were saved from the scrapper's torch.
Outside the United States
The metre gaugeMetre gauge
Metre gauge refers to narrow gauge railways and tramways with a track gauge of . In some African, American and Asian countries it is the main gauge. In Europe it has been used for local railways in France, Germany, and Belgium, most of which were closed down in mid 20th century. Only in Switzerland...
Central Railway of Brazil took delivery of four 2-8-8-4s from the German
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
firm of Henschel in 1937. They were the only narrow gauge locomotives of this wheel arrangement
Wheel arrangement
In rail transport, a wheel arrangement is a system of classifying the way in which wheels are distributed beneath a locomotive.. Several notations exist to describe the wheel assemblies of a locomotive by type, position, and connections, with the adopted notations varying by country...
, but not the only 2-8-8-4s outside the United States, they had the largest boilers ever used on a narrow-gauge Mallet.
Soviet Russia constructed two 2-8-8-4 locomotives at the Kolomna Locomotive Works. These were the P38 Class numbers P38.001 and P38.002. The first locomotive carried partial casings over the boiler and smokebox typical of the 1950s. P38.002 bore no such adornments and had a more conventional appearance. Both engines had tenders with part bogie and part fixed frame similar to the American 'centipede' tenders.