Norfolk & Western 2156
Encyclopedia
Norfolk & Western 2156 is the strongest-pulling extant steam locomotive
in the world, although it is not operational. It is a four-cylinder compound articulated (Mallet
) locomotive with a 2-8-8-2
(Whyte notation
) wheel arrangement. The Norfolk & Western Railway built it in 1942 at its Roanoke Shops
in Roanoke, Virginia
, and it was part of the Norfolk & Western's Y6a class. It was retired from regular rail service in July 1959, and today it is at the Museum of Transportation
in St. Louis, Missouri
, U.S.A.
of 152206 pound-forces (677 kN), and improvements in the 1950’s resulted in most of these locomotives (including N&W 2156) having their tractive effort increased to a measured 166000 pound-forces (738.4 kN), which necessitated adding about 28000 pounds (12.7 t) of lead to the front engine frame, to improve traction. (By comparison, the famous Union Pacific
Big Boy
locomotives developed 135375 pound-forces (602.2 kN) of tractive effort.) This pulling power is all the more remarkable insofar as the only successful steam locomotives that developed somewhat more tractive effort, the Virginian
AE class 2-10-10-2
s, pulled trains at about 8 mph (13 km/h), while the N&W Y6’s regularly pulled trains 50 mph (80 km/h), and some anecdotal evidence exists that they pulled trains successfully up to 63 mph (101 km/h).
N&W 2156 is also one of the Y6a's that received a new firebox with an extended combustion chamber of the type used on the Y6b class, which increased drawbar horsepower from 4400 hp (3.3 MW) at 20 mph (32 km/h) to 5600 hp (4.2 MW) at 25 mph (40 km/h).
locomotives
in 1952, and the related modifications to the locomotives, which have been a source of some debate among rail historians. N&W had coal traffic as arguably its most important source of revenue, and it had arguably the most modern and efficient steam locomotives of any major U.S. railroad. Accordingly, N&W resisted conversion from coal-burning steam locomotives to oil-burning Diesels longer than most major railroads. In 1952 N&W tested its A-class
and Y6b-class locomotives against a four-unit Electro-Motive Division (at that time, of General Motors
) F7
Diesel set. The tests indicated that fuel costs and similar items were roughly the same, and the test was considered a tie. However, eventually Diesels won out for lower maintenance and other operational costs.
Retrospective analyses of these tests have caused a few, even in published articles by knowledgeable historians, to assert that Diesel-locomotive-builder EMD and/or N&W used secretly-modified locomotives for these tests. If N&W's modified Y6b locomotive number 2197, in addition to its publicized improvements, had received secret upgrades that would not be appropriate for daily-use locomotives, then the claims of substantially upgraded performance were something of a fraud. However, the greater weight of evidence and analysis indicates that N&W did not cheat on these tests, and that the only improvements were the ones N&W publicized and later incorporated into many locomotives. Also, the major participants in this debate all appear to agree that N&W did ultimately modify most of its Y5, Y6, Y6a, and Y6b locomotives (including N&W 2156) with a new "intercepting/reducing valve" and ballast on the front engine, which significantly increased their tractive effort.
When Diesel locomotives took over the main-line steam operations, the Y6-type locomotives spent their last two years mostly on mine and other coal-field runs. During this period, specifically in July 1959, N&W donated 2156 to the Museum of Transportation.
in St. Louis. She sits cosmetically restored, but she has not operated in several decades. Although there is some sentiment for restoring 2156 to operational condition, doing so would be a massive undertaking that, even if possible, would probably cost millions of dollars and take years to complete.
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...
in the world, although it is not operational. It is a four-cylinder compound articulated (Mallet
Mallet locomotive
The Mallet Locomotive is a type of articulated locomotive, invented by a Swiss engineer named Anatole Mallet ....
) locomotive with a 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...
(Whyte notation
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...
) wheel arrangement. The Norfolk & Western Railway built it in 1942 at its Roanoke Shops
Roanoke Shops
thumb|250px|[[Norfolk Southern]] Roanoke Shops in 2004.The Roanoke Shops of the Norfolk and Western Railway in Roanoke, Virginia were founded in 1881 as the Roanoke Machine Works. It came under the control of the railroad in 1883. Locomotive production started in 1884 and 152 locomotives were...
in Roanoke, Virginia
Roanoke, Virginia
Roanoke is an independent city in the Mid-Atlantic U.S. state of Virginia and is the tenth-largest city in the Commonwealth. It is located in the Roanoke Valley of the Roanoke Region of Virginia. The population within the city limits was 97,032 as of 2010...
, and it was part of the Norfolk & Western's Y6a class. It was retired from regular rail service in July 1959, and today it is at the Museum of Transportation
Museum of Transportation
The Museum of Transportation of the St. Louis County, Missouri, United States Parks Department is a museum located in the Greater St. Louis area. It was first founded in 1944 by a group of individuals dedicated to preserving the past and has a wide variety of vehicles from American history...
in St. Louis, Missouri
St. Louis, Missouri
St. Louis is an independent city on the eastern border of Missouri, United States. With a population of 319,294, it was the 58th-largest U.S. city at the 2010 U.S. Census. The Greater St...
, U.S.A.
Historic significance
Norfolk & Western 2156 is the sole survivor of the railroad's Y5, Y6, Y6a, and Y6b classes (in final form referred to as the "Improved Y5/Y6 class"). These locomotives were among the hardest-pulling steam locomotives ever built. They were originally rated for a tractive effortTractive 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...
of 152206 pound-forces (677 kN), and improvements in the 1950’s resulted in most of these locomotives (including N&W 2156) having their tractive effort increased to a measured 166000 pound-forces (738.4 kN), which necessitated adding about 28000 pounds (12.7 t) of lead to the front engine frame, to improve traction. (By comparison, the famous Union Pacific
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....
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...
locomotives developed 135375 pound-forces (602.2 kN) of tractive effort.) This pulling power is all the more remarkable insofar as the only successful steam locomotives that developed somewhat more tractive effort, the Virginian
Virginian Railway
The Virginian Railway was a Class I railroad located in Virginia and West Virginia in the United States. The VGN was created to transport high quality "smokeless" bituminous coal from southern West Virginia to port at Hampton Roads....
AE class 2-10-10-2
2-10-10-2
Under the Whyte notation for the classification of steam locomotive wheel arrangements, a 2-10-10-2 is a locomotive with two leading wheels, two sets of ten driving wheels, and a pair of trailing wheels.Other equivalent classifications are:...
s, pulled trains at about 8 mph (13 km/h), while the N&W Y6’s regularly pulled trains 50 mph (80 km/h), and some anecdotal evidence exists that they pulled trains successfully up to 63 mph (101 km/h).
N&W 2156 is also one of the Y6a's that received a new firebox with an extended combustion chamber of the type used on the Y6b class, which increased drawbar horsepower from 4400 hp (3.3 MW) at 20 mph (32 km/h) to 5600 hp (4.2 MW) at 25 mph (40 km/h).
Steam versus Diesel tests, upgrades, and controversies
No discussion of N&W 2156 and its siblings would be complete without referring to their epic contest against new DieselDiesel engine
A diesel engine is an internal combustion engine that uses the heat of compression to initiate ignition to burn the fuel, which is injected into the combustion chamber...
locomotives
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...
in 1952, and the related modifications to the locomotives, which have been a source of some debate among rail historians. N&W had coal traffic as arguably its most important source of revenue, and it had arguably the most modern and efficient steam locomotives of any major U.S. railroad. Accordingly, N&W resisted conversion from coal-burning steam locomotives to oil-burning Diesels longer than most major railroads. In 1952 N&W tested its A-class
Norfolk & Western 1218
Norfolk & Western 1218 is a steam locomotive that at one time was the strongest-pulling operational steam locomotive in the world. It is a four-cylinder simple articulated locomotive with a 2-6-6-4 wheel arrangement. The Norfolk & Western Railway built it in 1943 at its Roanoke Shops in Roanoke,...
and Y6b-class locomotives against a four-unit Electro-Motive Division (at that time, of General Motors
General Motors
General Motors Company , commonly known as GM, formerly incorporated as General Motors Corporation, is an American multinational automotive corporation headquartered in Detroit, Michigan and the world's second-largest automaker in 2010...
) F7
EMD F7
The EMD F7 was a Diesel-electric locomotive produced between February 1949 and December 1953 by the Electro-Motive Division of General Motors and General Motors Diesel . It succeeded the F3 model in GM-EMD's F-unit sequence, and was replaced in turn by the F9. Final assembly was at GM-EMD's La...
Diesel set. The tests indicated that fuel costs and similar items were roughly the same, and the test was considered a tie. However, eventually Diesels won out for lower maintenance and other operational costs.
Retrospective analyses of these tests have caused a few, even in published articles by knowledgeable historians, to assert that Diesel-locomotive-builder EMD and/or N&W used secretly-modified locomotives for these tests. If N&W's modified Y6b locomotive number 2197, in addition to its publicized improvements, had received secret upgrades that would not be appropriate for daily-use locomotives, then the claims of substantially upgraded performance were something of a fraud. However, the greater weight of evidence and analysis indicates that N&W did not cheat on these tests, and that the only improvements were the ones N&W publicized and later incorporated into many locomotives. Also, the major participants in this debate all appear to agree that N&W did ultimately modify most of its Y5, Y6, Y6a, and Y6b locomotives (including N&W 2156) with a new "intercepting/reducing valve" and ballast on the front engine, which significantly increased their tractive effort.
Operational history
Norfolk & Western used 2156 and the other Y6-class locomotives primarily for slower, heavy freight trains in the more mountainous districts. Although they were used throughout the N&W, their primary work occurred on the Pocahontas, Radford, and Shenandoah Divisions. They mostly hauled manifest freight and coal trains.When Diesel locomotives took over the main-line steam operations, the Y6-type locomotives spent their last two years mostly on mine and other coal-field runs. During this period, specifically in July 1959, N&W donated 2156 to the Museum of Transportation.
Current status
Today N&W 2156 is one of the attractions at the Museum of TransportationMuseum of Transportation
The Museum of Transportation of the St. Louis County, Missouri, United States Parks Department is a museum located in the Greater St. Louis area. It was first founded in 1944 by a group of individuals dedicated to preserving the past and has a wide variety of vehicles from American history...
in St. Louis. She sits cosmetically restored, but she has not operated in several decades. Although there is some sentiment for restoring 2156 to operational condition, doing so would be a massive undertaking that, even if possible, would probably cost millions of dollars and take years to complete.
External links
- builder's photo of N&W 2156, fireman's (left) side, Virginia Tech collection
- builder's photo of N&W 2156, front, Virginia Tech collection
- photo of N&W 2156 during operational period, front-quarter view of fireman's (left) side, Virginia Tech collection
- on display at the Museum of Transportation, July 22, 2007
