In the Whyte notation, a 2-8-2 is a railroad steam locomotive that has one leading axle followed by four powered driving axles and one trailing axle. This configuration of steam locomotive is most often referred to as a Mikadocite web| url=http://www.railway-technical.com/st-glos.shtml| title=Steam Locomotive Glossary| work=Railway Technical Web Pages| date=2007-06-28| accessdate=2008-02-08| ] (frequently shortened to Mike), but it is also referred to as a MacArthur.cite web| url=http://trains.com/trn/glossary/default.aspx?list=4&fl=m| title=Glossary Of Common Railroad Terms: M| publisher=Kalmbach Publishing| accessdate=2008-01-29| ] The 2-8-2 was particularly popular in North America, but was also used in continental Europe and elsewhere.

Other equivalent classifications are:

UIC classification: 1D1 (also known as German classification and Italian classification)

French classification: 141

Turkish classification: 46

Swiss classification: 4/6

The 2-8-2 arrangement allows the locomotive's firebox to be placed behind, instead of above, the driving wheels, allowing a large firebox that could be both wide and deep. This supported a greater rate of combustion and thus a greater capacity for steam generation, allowing for more power at higher speeds. Allied with the larger driving wheel diameter possible when they did not impinge on the firebox, this meant that the 2-8-2 was capable of higher speeds with a heavy train than a 2-8-0.


The very first 2-8-2 locomotive was built in 1884. They were originally named "Calumets" by Angus Sinclair, in reference to the 2-8-2 engines built for the Chicago & Calumet Terminal railroad. This name did not stick, though. [LeMassena, p. 6]

The class name "Mikado" originates from a group of 2-8-2 locomotives that were constructed in 1897 in the U.S. for the Nippon Railway of Japan. [ [http://www.jrtr.net/jrtr29/back.html Japan Railway & Transport Review No. 29] - retrieved 26th October 2006] In 1885, the Gilbert and Sullivan opera "The Mikado" premiered, so the name was on the minds of many in America, where the opera achieved great popularity.

The 2-8-2 was one of the more common configurations in the first half of the 20th century before dieselization. Nearly 2,200 of this type were constructed by ALCO, Lima and Baldwin based on designs of the USRA between 1917 and 1944. Of all of the USRA designs, the Mikado proved to be the most popular.

"Mikado" remained the class name until the Attack on Pearl Harbor in 1941. Seeking a more "American" name, MacArthur came into use to describe the locomotive type; this name is based on General Douglas MacArthur. Since the war, the class name "Mikado" has again become the most common name for this locomotive type. [http://www.steamlocomotive.com/mikado/ steamlocomotive.com - The Mikado Type Locomotive] - retrieved 26th October 2006]

Geographical distribution

United States

The 2-8-2 saw great success in the United States, mostly as a freight locomotive. It largely replaced the 2-8-0 "Consolidation" type as the heavy freight locomotive type in the second decade of the 20th century. Tractive effort was similar to the best 2-8-0s, but a developing requirement for higher speed freight trains drove the shift to the 2-8-2. The type was in turn pushed from the top-flight trains by larger freight locomotive arrangements such as 2-10-2, 2-8-4, 2-10-4 and articulated locomotives, but no successor type became ubiquitous and the "Mike" remained the most common road freight locomotive with most railroads until the end of steam. In excess of 14,000 of this type were built for North American service, which comprised approximately one-fifth of all locomotives in service at the time. The heaviest Mikados were Great Northern's class O-8, which also had the heaviest axle load (81,250 lb.) of any steam locomotive.

Almost all North American railroads rostered the type; notable exceptions included Boston and Maine Railroad, Delaware and Hudson Railway, St. Louis Southwestern Railway and Norfolk and Western Railway. The largest users included New York Central Railroad (715 examples), Baltimore and Ohio Railroad (610), Pennsylvania Railroad (579), Illinois Central Railroad (565), Milwaukee Road (500), and the Southern Railway (435). [http://www.steamlocomotive.com/mikado/ steamlocomotive.com - The Mikado Type Locomotive] - retrieved 26th October 2006]

United Kingdom

The 2-8-2 type saw little success on British rails. Sir Nigel Gresley of the London and North Eastern Railway designed two Mikado types of note; the P1 was a freight derivative of his famed A1 4-6-2s, inspired by the Pennsylvania Railroad's twin K4s 4-6-2s and L1s 2-8-2s. Two were built, but there was never really much call for their ability and they remained underutilised throughout their short existence. [ [http://www.lner.info/locos/P/p1.shtml LNER Encyclopedia - The Gresley P1 Mineral 2-8-2 (Mikado) Locomotives] - retrieved 26th October 2006]

Gresley's other class of Mikados was his P2 class. These were express passenger locomotives rather more inspired by European influences than American. They were built to haul heavy expresses north of Edinburgh in hilly terrain, where Gresley thought the extra tractive effort possible with a 2-8-2 might serve well. Unfortunately, poor self-centering on the leading truck meant that the lead driving wheels wore against the rails on tighter curves, being hard on both track and wheels. Gresley's successor Edward Thompson converted the P2s into (rather unattractive, by most opinions) Pacifics. [ [http://www.lner.info/locos/P/p2.shtml LNER Encyclopedia - The Gresley P2 Passenger 2-8-2 (Mikado) Locomotives] - retrieved 26th October 2006]

The Great Western Railway operated a class of 54 2-8-2 tank engines designed by C. B. Collett. As early as 1906 their then chief mechanical engineer, G. J. Churchward, planned a class of 2-8-2 tank engines to handle heavy coal trains in South Wales. However the plan was abandoned as it was feared they would be unable to handle the sharp bends found on Welsh mineral branches. Instead, Churchward designed the 4200 Class of 2-8-0 tank engines, of which nearly 200 were built. In the 1930s, coal traffic declined, and many of these engines stood idle; they could not be switched to other duties because of their limited operating range. Collett, as Churchward's successor, decided to rebuild some of the 4200 Class engines as 2-8-2s. The addition of a trailing axle increased the engines' operating ranges by allowing more coal and water storage. In all 54 engines were modified in this way. The 7200 Class tank engines as they were known remained in service until the end of steam in Britain in the early 1960s.


German 2-8-2s were built in both passenger and freight types. The passenger locomotives were used mainly in mountainous terrain (BR 39). Although eclipsed by the success of German 2-10-0 designs, many successful 2-8-2 freight locomotives were also built, all of type BR 41. The third type of German 2-8-2 locomotive was the tank locomotive (BR 86, BR 93).


The 4-cylinder compound class 470, developed in 1914 by Karl Gölsdorf, was built for express trains on mountain lines. From 1927 some the locomotives were rebuilt to 2-cylinder overheated steam locomotives class 670. Numbered class 39 from 1938 on, they remained in service until 1957.


France built a fairly large number of 2-8-2s, both tender-hauling and tank locomotives.

141 R

The American and Canadian-built 141 R were the most widespread locomotives France has ever had, with 1340 units ordered and 1323 operated (sixteen engines were lost at sea in a storm off the coast of Newfoundland "en route" to France, one was lost in Marseille harbour). They were praised for being easy to maintain and have proved very reliable, that is why they served until the very end of the steam era (1975). Today, twelve locomotives have been preserved.

141 P

The most powerful French Mikado was the 141 P. At about 3,300 drawbar hp, these engines were among the most efficient steam locomotives in the world thanks to their Compound design [Westwood, J.N. 1977. Locomotive designers in the age of steam. ] . They could burn 30 % less fuel and 40 % less water than their "R" counterparts, but could not compete when it comes to reliability. Every unit has been scrapped.


Italy built two 2-8-2 types, the Gruppo 746 for heavy passenger trains and the Gruppo 940, a tender engine for freight and mountain service. Gruppo 740 was more a 2-8-0 with an extra bissel to support the coal bunker and it was indeed the tank version of the 2-8-0 Gruppo 740 tender locomotive.


The need to build locomotives that could be converted from 5 ft 3 in (1600 mm) broad gauge to RailGauge|ussg standard gauge operation without major reengineering led to the introduction of Mikado locomotives by Victorian Railways in the 1920s. Whereas previous 2-8-0 "Consolidation" type locomotives featured long, narrow fireboxes between the frames that made gauge conversion impractical, the N class light lines and X class heavy goods locomotives both featured a wide firebox positioned behind the driving wheels and above the frames. [Pearce et al, p. 14]
South Australian Railways employed no fewer than four distinct classes of 2-8-2 locomotive, the locally designed 700 and 710 class, the 740 class (originally built by Clyde Engineering for China, but purchased by SAR after the order was cancelled in the wake of the Chinese Communist Revolution) and the 750 class (a group of ten surplus VR N class locomotives). [ [http://www.natrailmuseum.org.au/exhibits/nrm_752.html National Railway Museum - Port Adelaide] 752 page - retrieved 21st October 2006]

American-design Mikado locomotives, such as the Baldwin-built NSWGR D59 class and the QR AC16 class, were also introduced after World War II to assist with the postwar rebuilding of Australian railways.

The last new class of mainline steam locomotive introduced in Australia, WAGR's V class heavy freight locomotive of 1955, was a 2-8-2. [ [http://www.csse.monash.edu.au/~ajh/cgi-bin/viewtrains.py John Hurst Railway Pages] - retrieved 26th October 2006]

New Zealand

Only one 2-8-2 locomotive ever operated on New Zealand's national rail network, and it was not even ordered by the New Zealand Railways Department, who ran almost the entire network. The locomotive was ordered in 1901 from Baldwin by the Wellington and Manawatu Railway Company (WMR) for use on their main line's steep section between Wellington and Paekakariki and entered service on 10 June 1902 classified as No. 17. At the time, it was the most powerful locomotive in New Zealand and successfully performed its intended tasks. When the WMR was incorporated into the national network in 1908, the Railways Department reclassified No. 17 as the solitary member of the BC class, BC 463, and the locomotive continued to operate on the Wellington-Paekakariki line until it was withdrawn on 31 March 1927.

South Africa

The narrow gauge, two feet or 610 mm, line from Port Elizabeth to Avontuur operated 21 locomotives of the NG15 class from 1960 onwards. These locomotives had been moved to the line after the narrow gauge, 600 mm, Otavi Railway in South West Africa had been replaced by a Cape standard gauge, 42 inches or 1067 mm, railway.

The NG15s had been built in five batches from 1931 to 1957 specifically for service on the Otavi Railway and were a development of a design dating from 1912.


Canadian National Railway operated a few Mikado locomotives:

* R-1 class - 1 (#3000)
* R-2 class - 29 (#300-329)
* S-1/S-4 class - ? (#3198-4097)

Canadian Pacific used Mikado locomotives for passenger and freight trains throughout Canada. Mostly in the Rocky Mountains where the standard 4-6-2 Pacifics and 4-6-4 Hudsons could not provide enough traction to handle the steep mountain grades. A perfect example of a preserved Canadian Pacific Mikado is Canadian Pacific 5468, on display in Revelstoke BC.

See also

* USATC S200 Class - a class of 2-8-2 that was built by American manufacturers for use in Europe during World War II
* USATC S118 Class



External links

* [http://www.steamlocomotive.com/mikado/ Mikados]

Wikimedia Foundation. 2010.