4-6-4

Under the Whyte notation for the classification of steam locomotives, 4-6-4 represents the wheel arrangement of four leading wheels on two axles (usually in a leading truck), six powered and coupled driving wheels on three axles, and four trailing wheels on two axles (usually in a trailing truck).

Other equivalent classifications are:
UIC classification: 2C2 (also known as German classification and Italian classification)
French classification: 232
Turkish classification: 37
Swiss classification: 3/7
Russian classification: 2-3-2

The type is sometimes called the Hudson or Baltic.^[1]

Usage

The 4-6-4 tender locomotive is best seen as combining the basic nature of the 4-6-2 'Pacific' type with an improved boiler and larger firebox that required extra support at the rear of the locomotive. Generally the available tractive effort was little different from that of the Pacific, but steam-raising ability was increased, giving more power at speed. 4-6-4s were best suited to high-speed running across flat country. The type has fewer driving wheels than carrying wheels and thus a smaller percentage of the locomotive's weight is available for traction compared to other types. For starting heavy trains and slogging on gradients, a 4-6-4 really needs a booster engine, but for sustained long grades, more pairs of driving wheels are better.

The world speed record for steam locomotives was at least twice held by a 4-6-4; the Milwaukee Road's class F6 #6402 in 1934 with 103.5 mph (166.6 km/h), and German 05 002 in 1936 with 124.5 mph (200.4 km/h).^[2]

History (tender locomotives)

4-6-4 tender locomotives were first introduced in 1911 and were widely used throughout the 1920s, 30s and 40s.

France

The first examples in the world were the two four-cylinder compound locomotives designed by Gaston du Bousquet for the Chemin de Fer du Nord and built at the company's workshops in 1911. They were allegedly designed to pull the Paris - St Petersburg express, and hence the title Baltic. But the name was obviously a logical extension of the convention started with 'Atlantic' and 'Pacific'. Their most remarkable feature was perhaps the arrangement of the two low-pressure inside cylinders en echelon so as to accommodate the very large bore. One had a water-tube firebox. They were not multiplied, but gave place to the highly successful Nord Pacifics and Super-Pacifics which followed.^[3] One survives, in sectioned form in the Cité du train at Mulhouse in France. See http://www.railfaneurope.net/pix/fr/steam/misc_Nord/pix.html

France also produced some of the last Baltics. In 1938 Marc de Caso, the last Chief Mechanical Engineer of the Nord, originated the construction of eight Baltics, all delivered to the newly created SNCF, the nationalised French railway system. Of these eight, the four 232.S class locomotives were built as four-cylinder compounds, with rotary cam poppet valve gear, later replaced by Walschaerts gear driving oscillating cams; the three 232.R class locomotives were built as three-cylinder simples, also with rotary cam poppet valve gear. The compounds clearly outperformed the simples.

The eighth, and final, French Baltic completed in 1949 as 232.U.1, and is also preserved in Mulhouse. This was another four-cylinder compound with Walschaerts valve gear, but in this final form driving very large and light piston valves. It proved capable of more than 4000 ihp.^[4]

One of those engines was the theme of a fashion photoshot in Stanley Donen's movie Funny face (1957).

There would have been further classes of French 4-6-4s had either Chapelon's pre-war (four-cylinder compound) or post-war (three-cylinder compound) schemes gone ahead.^[5]

Indonesia

The C27 steam locomotive was introduced to Indonesia by the Dutch colonial administration, between the years 1916-1922. 39 locomotives were ordered from several manufacturers: Werkspoor, Amsterdam, Netherlands, Armstrong Whitworth Newcastle upon Tyne and SLM (Schweizerische Lokomotiv-und Maschinenfabrik) Winterthur, Switzerland. The class was designed to meet the requirements, among others, of a tractive force of at least 6,000 kg, to haul trains weighing 400 tons at a speed of 50 km/h on a 0.5 percent incline and bends with a radius of 180 m. The locomotives must also be able to turn corners with a sharp radius of 120 m at a speed of 80 km/h. The C27 class was used on railway lines around Jakarta, Bandung and Surabaya.

In the years 1925-1930 railway electrification was carried out around Jakarta. The C27 locomotives were moved to secondary lines, for example, in Banten (Merak-Tanah Abang), the lines around Kertosono-Blitar, and also between Purwokerto, Kutoarjo and Purworejo.

The C28 express passenger locomotive is one of the most popular in Indonesia, achieving speeds of up to 95 km/h. This steam locomotive was named the world's fastest locomotive for the narrow gauge (1067 mm) which is 110 km/h. In addition, proven reliability because these locomotives could travel at the same speed in both directions. It was used on the Jakarta-Bandung, Jakarta-Surabaya and Malang-Surabaya routes. During the Dutch colonial era the term 'VLUGGE VIER' was used for the Jakarta-Bandung route with the distance 175 km, runs 4 times a day and takes about 2 hours 45 minutes and the speed of 65 km/h. Express trains only stop for 1 minute at Karawang, Cikampek and Purwakarta. In addition, this locomotive has also been used on a series of express trains Java Nacht Express and Eendaagsche Express.

C28 locomotive in Indonesia there are 58 units made by three different manufacturers, namely Henschel, Sächsische Maschinenfabrik and Maschinenfabrik Esslingen in Germany). Locomotive C28 was also instrumental in helping to move the entourage of Ir. Soekarno to Yogyakarta on 3 January 1948.

North America

The first example in North America was built in 1927 by ALCO for the New York Central Railroad, and to the NYC's design. The locomotive proved very successful and was named the Hudson type after the Hudson River. The NYC and its Boston & Albany, Big Four and Michigan Central, subidiaries acquired 275 Hudsons, the largest fleet in North America, of several different types.

The Milwaukee Road could have produced the first American 4-6-4; its design was earlier than the NYC's, but financial constraints delayed the project, and Milwaukee's locomotives emerged later. The Milwaukee called them Baltics, following European practice started in France. The initial order of 14 class F6 locomotives was joined by 8 more of class F6a a year later in 1931, and in 1938 the road acquired 6 streamlined F7 Baltics with shrouds designed by noted industrial designer Otto Kuhler. These took over the Milwaukee's crack Hiawatha expresses from the class A 4-4-2 Atlantics, and were among the fastest steam locomotives of all time. Schedules of many of these trains required extended running at 100 mph (160 km/h).

The second-largest buyer of the type in North America was the Canadian Pacific Railway, which bought 65 (numbered 2800-2864). designated "H1" class and were highly successful in improving service and journey times on the CPR's transcontinental routes. The newer CPR Hudsons were called Royal Hudsons (numbered 2820-2864) and were semi-streamlined. Royal permission was given for these locomotives to bear the royal crown and arms after locomotive 2850 hauled King George VI across Canada in 1939. A total of five CPR Hudsons survive today, Canadian Pacific 2816 (H1b) is the sole remaining non-streamlined CPR Hudson remaining. 2816 is operational and pulls excursions for CP and was repatriated to CP in 1998. The other remaining H1 Hudsons are the famed royal hudsons. As of 2008 numbers 2839, 2850, and 2858 are on display in museums in California (2839), Quebec (2850) and Ontario (2858). 2860, the first CPR Hudson built Royal, is operational and based in British Columbia. The CP Hudsons are, as of 2008, the only Hudsons operational in North America.

Twenty railroads in North America owned 4-6-4s; these include, as well as the foregoing, the Santa Fe (16 locomotives), Baltimore and Ohio Railroad (4), Canadian National (5), Chesapeake & Ohio (18), Burlington (14), Chicago & North Western (9), Lackawanna (5), Illinois Central (1 — the only example of a Hudson designed for freight haulage), Maine Central (2), Ferrocarriles Nacionales de México (National Railways of Mexico — 10), New Haven (10), Nickel Plate (8), Frisco, and Wabash (7).^[6]

Many 4-6-4s were similar in concept to the NYC's Hudsons, with 79–80-inch (2.007–2.032 m) driving wheels, but most of these were a little larger than the NYC's locomotives. Included in this group are the Milwaukee's F6 and F6a, the Canadian National K-5-a and Canadian Pacific locomotives, the Burlington's S-4, the New Haven's I-5, and the Lackawanna's 1151 class.

In the late 1930s three railroads ordered larger, faster 4-6-4s with 84-inch (2.1 m) drivers: Milwaukee's F7, the Santa Fe's 3460 class, and the Chicago and Northwestern's class E-4. The Milwaukee and CNW locomotives were all streamlined, while one of the Santa Fe's was.

The other main grouping of North American 4-6-4s are the lightweights, which include the Nickel Plate's L-1 class locomotives, the Maine Central's class D, and the Nacionales de México class NR-1. In these, the extra wheels were used to reduce the axle load in comparison to a 4-6-2 "Pacific".

Finally, there were many one-off and experimental 4-6-4s. A number were rebuilds from Pacifics, or in some cases other designs. Baltimore & Ohio built four examples as experimentals, using Colonel Emerson's water-tube fireboxes, but eventually turned to diesels instead.^[7] The Illinois Central rebuilt a 2-8-4 into its only Hudson; Illinois Central No. 1 was not a success, and was not repeated. The Wabash had rebuilt its class P1 from 2-8-2 Mikados

Because the 4-6-4 design was really only good for express passenger trains, which dieselized early, Hudsons were early candidates for withdrawal and scrapping. None of the NYC's locomotives survive; neither do the Milwaukee's. Five Canadian Pacific Hudsons survive, these include four Royal Hudsons, along with the non-streamlined Canadian Pacific 2816 which was restored by the Canadian Pacific railway in 2001. Four of the Burlington's, two each of the Santa Fe's and Canadian National's, and single examples from the C&O, NdeM and Nickel Plate. While the Pennsylvania Railroad did not have any 4-6-4 steam locomotives the PRR had a fleet of 4-6-4 electrics classified P5a.

India

There were two classes of 4-6-4 tender engines in India, both very early in the history of the configuration, and also of unusually narrow gauge. The 2-foot-6 gauge Barsi Light Railway G class were nine locomotives built by Nasmyth, Wilson & Co. (5 in 1928, 2 in 1930) and W. G. Bagnall (2 in 1939). The 2-foot gauge Scindia State Railway ND class were four locomotives built in 1928 by Kerr, Stuart & Co.

British Isles

The only 4-6-4 tender locomotive in Great Britain was LNER No. 10000, built in 1930 as an experimental high-pressure compound locomotive with an experimental high-pressure water-tube boiler, and known as the "hush-hush" locomotive on account of the great secrecy with which it was built. The experiment proved much less successful than hoped, and in 1936 it was rebuilt along the lines of a streamlined LNER Class A4 Pacific, though it retained its unique wheel arrangement. It was the only locomotive of Class W1. Its trailing wheels were arranged uniquely; instead of being in one 4-wheel trailing truck, the first pair were instead a Cartazzi axle, as typical of LNER Pacific practice, being mounted in a rigid frame but allowed sideways deflection against a centering force. The second pair were in a two-wheel trailing truck. After its rebuild, the W1 was easily distinguishable from an A4 at a glance, without looking for the extra trailing wheels, by the fact that it was never named; it was therefore known to train spotters as "the no-name streak". (The proposed name Pegasus was never issued.)

However the London Midland and Scottish Railway seriously considered a 4-6-4 development of its Coronation Pacific for Anglo-Scottish services in the years just before the Second World War. This would have had 300 psi boiler pressure, four cylinders, mechanical stoking and many features in common with a 4-8-4 fast freight engine. But the advent of the war prevented this entirely practical proposition from ever seeing the light of day.^[8]

Germany

In addition to a number of 4-6-4 tank locomotives (the best known being the K.P.E.V. T18, later numbered as class 78), three 4-6-4 tender locomotives were built in 1935. Classified as Class 05, they were designed for high speed running; they were 3-cylinder locomotives, with giant 90½ inch driving wheels and powerful clasp brakes on all wheels. The first two locomotives, 05 001 and 05 002 were conventional locomotives, but the third, 05 003 was built as a cab forward, burning pulverised coal. All were built streamlined, in shrouds that covered the locomotives almost to the railhead. In 1936, 05 002 set a world speed record of 124.5 mph (200.4 km/h) which soon afterwards was beaten by the LNER's famous Mallard.

All three survived World War II and were rebuilt as conventional, unstreamlined locomotives in 1950 with new boilers, in which form they worked until 1957 when electric locomotives took over the high-speed routes. The first locomotive, 05 001, was restored to its original streamlined configuration and placed into a museum in 1961.

Soviet Union

Only 3 prototype Hudsons were built in the former Soviet Union in 1937-1938. They all were streamlined, the only streamlined series of the Soviet steam locomotives, although a later postwar P36 series was semi-streamlined. 2 were built in Kolomna (2-3-2K series, internal designation P12, chief designer Lev Lebedyanskii) and were used to haul "Red Arrow" passenger train between Moscow and Leningrad. There were plans to build up to 10 2-3-2K locomotives to haul all express passenger trains between Moscow and Leningrad, but these plans were interrupted by World War II. Their power was up to 3,070 hp (2,290 kW). One was built in Voroshilovgrad (2-3-2V locomotive, number 6998). This locomotive was never used for the mainline service. All were scrapped in the fifties.

Japan

The Japanese National Railways built three classes of rather advanced, American style 3 ft 6 in (1,067 mm) gauge Hudsons, classes C60 (47 built), C61 (33 built) and C62 (49 built), between 1947 and 1953. The C60 and C61 were smaller and the C62 was a larger locomotive, filling the small Japanese loading gauge. All were officially rebuilt from earlier locomotives of different arrangement, but it is believed that this was for accounting purposes rather than any real cost saving; the parts re-used appear to have been minimal. They were all equipped with disk drivers and much in the way of American-style appliances, although they had British-style smokebox doors.

Australia

Seventy R class "Hudson" 4-6-4 tender locomotives, the only class of this configuration in Australia, were introduced by the Victorian Railways in 1951 for mainline express passenger operations. However, the introduction in 1952 of B class diesel electric locomotives saw the R class almost immediately relegated to secondary passenger and freight use, with many put into storage at depots around the state. A number were preserved and some of these continue to operate on special excursion trains.^[9]

With the privatisation of regional passenger operations in Victoria in the mid-1990s, two R class locomotives were brought into normal revenue service for regularly scheduled mainline passenger trains between Melbourne and Warrnambool. The locomotives featured a number of modifications to allow for reliable high speed operation, including dual Lempor exhausts, oil firing, and the addition of a diesel control stand for multiple unit operation. The use of these R class locomotives on the Warrnambool line did not continue after the demise of the private operator in 2004.^[10]

Tank locomotives

The 4-6-4T was also a fairly common wheel arrangement for a passenger tank locomotive. As such it was essentially the equivalent of a 4-6-0 locomotive with the tender replaced by a tank and bunker carried by a four-wheel truck.

South Africa

The first 4-6-4T tank locomotive was rebuilt from a Natal Government Railways K&S Class 4-6-0T in 1896. The sole locomotive later became the South African Railways Class C2. The new design was later used as the basis of the Class E, supplied by Neilson, Reid and Company in 1902. In 1904 the Central South African Railways introduced the Class F, built by the Vulcan Foundry. In 1905 the Vulcan Foundry also supplied two rack railway locomotives to South Africa.^[11]

Later 4-6-4T locomotives included the Class J built by Nasmyth Wilson and Company and the Class K built by the North British Locomotive Company in 1915.^[12]

British Isles

A number of 4-6-4T tank locomotives were built for various British railway companies. The first and longest-lived were two built by Nasmyth Wilson in 1904 for the narrow-gauge County Donegal Railways. Both later superheated, one lasted (derelict) until 1967.^[13]

The first standard-gauge examples were Robert Harben Whitelegg's design for the London, Tilbury and Southend Railway in 1912, although not delivered until after the LT&SR had been taken over by the Midland Railway, where they were the 2100 class. The London, Brighton and South Coast Railway built seven L (Remembrance) class tank locomotives between 1914 and 1922. The first examples suffered from instability problems until rebuilt with well-tanks. These high-speed tank locomotives hauled the famous Southern Belle until electrification of the Brighton Main Line in 1933, after which they were converted into N15X class 4-6-0 tender locomotives, remaining in service until 1957.^[14]

The Lancashire and Yorkshire Railway, Furness Railway, Belfast and County Down Railway and the Glasgow and South Western Railway (Whitelegg's second attempt) also had classes of this wheel arrangement. Of these the LYR examples were very rare in having four cylinders, but were too large and too complex for the duties they performed; the BNCR unsuperheated tanks were spectacularly unsuccessful because of poor valve settings; while the Furness tanks, also unsuperheated and almost uniquely with inside cylinders, were very popular with their crews.^[15]

Netherlands

The Nederlandse Spoorwegen (Dutch State Railways) had ordered six 4-6-4T locomotives from Beyer, Peacock and Company in 1913. A follow-up order for 34 locomotives was only partly delivered when, during a down-turn in traffic caused by World War I, the Dutch authorities cancelled the remainder of the order. Fourteen undelivered locomotives were sold to the War Department for use on the Western Front, where air-braked passenger locomotives were in short supply. They were assigned Railway Operating Division numbers 1–12, 14 and 15 and were used on ambulance and troop trains as well as civilian passenger trains in the British sector. After the war they were sold to the Chemin de fer du Nord, who numbered them 3.871 to 3.884. All fourteen passed to the SNCF who renumbered them 232.TB.1 to 232.TB.14. Two were withdrawn in 1946, but the remainder lasted until 1950–1951. They were outlasted by the 26 in service with the NS, twenty of which were still in service in 1952. They had been renumbered 6001–6026, from the original 1201–1240 series.^[16]

Canada

The Grand Trunk Railway had six K2 class 4-6-4T locomotives built by Montreal Locomotive Works in September 1914 for suburban service. Numbered 1540 to 1545, after being absorbed by Canadian National Railways, they were classified as X-10-a, and renumbered 45 to 50. Three are preserved: GT 1541 (CN 46), GT 1542 (CN 47), at Steamtown National Historic Site, Scranton, Pennsylvania, and GT 1544 (CN 49) at the Canadian Railway Museum, Delson, Quebec.

Australia

The 4-6-4T tank locomotive configuration was a popular type with the Western Australian Government Railways. The D class and its successors, the Dm and Dd Class all featured this arrangement.

In fiction

In the anime Galaxy Express 999, the legendary express's locomotive, C6250, is a 4-6-4, based on a JNR C62. Also, in the SpongeBob SquarePants episode "The Great Patty Caper", the loco that hauls The Oceanic Express train is a 4-6-4 tender locomotive.

See also

• Category:4-6-4 locomotives

References

External links

• 4-6-4 or Hudson
• German Wikipedia on 4-6-4 class 05
• Anatomy of West Coast Railway's "Super" R Class