4-6-4 Hudson Steam Locomotive
The 4-6-4 tender locomotive was first introduced in 1911 and throughout the 1920s to 1940s, the wheel arrangement was widely used in North America and to a lesser extent in the rest of the world. The type combined the basic design principles of the 4-6-2 Pacific type with an improved boiler and larger firebox that necessitated additional support at the rear of the locomotive. In general, the available tractive effort differed little from that of the Pacific, but the steam-raising ability was increased, giving more power at speed. The 4-6-4 was best suited to high-speed running across flat terrain. Since the type had fewer driving wheels than carrying wheels, a smaller percentage of the locomotive's weight contributed to traction, compared to other types. Like the Pacific, it was well suited for high speed passenger trains, but not for starting heavy freight trains and slogging on long sustained grades, where more pairs of driving wheels are better.
The first 4-6-4 tender locomotive in the world was a four-cylinder compound locomotive, designed by Gaston du Bousquet for the Chemin de Fer du Nord in France in 1911. Since it was designed for the Paris-Saint Petersburg express, it was named the Baltic after the Baltic Sea, which was a logical extension of the naming convention that started with the 4-4-2 Atlantic and 4-6-2 Pacific.
The first 4-6-4 in the United States of America, the J-1 of the New York Central Railroad, was built in 1927 to the railroad’s design by the American Locomotive Company (ALCO). There, the type was named the Hudson after the Hudson River.
The world speed record for steam locomotives was held by a 4-6-4 at least twice. In 1934, the Milwaukee Road’s class F6 No. 6402 reached 103.5 miles per hour (166.6 km per hour) and, in 1936, the German class 05.002 reached 124.5 miles per hour (200.4 km per hour). That record was broken by the British 4-6-2 Pacific no. 4468 Mallard on 3 July 1938, when it reached 126 miles per hour (203 km per hour), still the world speed record for steam traction.
The 4-6-4T was also a fairly common wheel arrangement for passenger tank locomotives. As such, it was essentially the tank locomotive equivalent of a 4-6-0 tender locomotive, with water tanks and a coal bunker supported by four trailing wheels instead of in a tender. In New Zealand, all 4-6-4T locomotives were tank versions of 4-6-2 locomotives.
The first known 4-6-4 tank locomotive was rebuilt from a Natal Government Railways (NGR) K&S Class 4-6-0T which was modified in 1896 to enable it to run equally well in either direction on the Natal South Coast line, where no turning facilities were available at the time. This sole locomotive later became the Class C2 on the South African Railways (SAR). The first known locomotive class to be designed with a 4-6-4T wheel arrangement, the NGR’s Class F tank locomotive, was based on this modified locomotive and built by Neilson, Reid and Company in 1902. These became the Class E on the SAR in 1912.
The Chicago, Milwaukee, St. Paul and Pacific Railroad (Milwaukee Road) could have produced the first American 4-6-4 since its design work was done earlier than that of the NYC, but financial constraints delayed the project and the Milwaukee's locomotives only emerged in 1930. The Milwaukee called them Baltic, following the European practice started in France. The initial order of fourteen Class F6 locomotives was followed by eight more Class F6a locomotives in 1931 and, in 1938, the Milwaukee acquired six streamlined Class F7 Baltics with the shrouds. These took over the Milwaukee's crack Hiawatha express trains from the Class A 4-4-2 Atlantics and were among the fastest steam locomotives of all time. The schedules of many of these trains required extended running at 100 miles per hour (160 km per hour).
In addition to the Milwaukee’s streamlined Class F7, two other railroads ordered larger and faster 4-6-4 locomotives with 84 inches (2,134 mm) drivers in the late 1930s. These were the Atchison, Topeka and Santa Fe Railway (Santa Fe) with its 3460 Class and the Chicago and North Western (CNW) with its Class E-4. The Milwaukee and CNW locomotives were all streamlined, and only one of the Santa Fe locomotives, the 3460 Blue Goose.
In 1937, the Chicago, Burlington and Quincy Railroad (Burlington Route) needed backup locomotives for their streamlined diesel-hauled Zephyr passenger trains. Their solution was to streamline their Baldwin-built no. 3002 in their main Iowa shops. The locomotive was renumbered as no. 4000 and given the name Aeolus, after the mythical keeper of the winds. A second streamlined 4-6-4 was built for this purpose and numbered 4001.
There were also some once-off and experimental 4-6-4 locomotives. A number were rebuilt from 4-6-2 Pacific locomotives, or in some cases from other designs.
The Baltimore and Ohio Railroad (B&O) built four as experimental locomotives between 1933 and 1936, using Colonel Emerson’s water-tube fireboxes, but eventually turned to diesel-electric traction instead.
In 1937, the Illinois Central Railroad (IC) rebuilt a 2-8-4 Berkshire into its only Hudson, the Illinois Central No. 1, which was not a success and was not repeated.
The Wabash Railroad rebuilt its seven Class P1 Hudsons from their unsuccessful K-4 and K5 Class 2-8-2 Mikado locomotives.
The second-largest user of the 4-6-4 type in North America was the Canadian Pacific Railway with 65 H1a to H1e class locomotives, numbered 2800 to 2864 and built by Montreal Locomotive Works (MLW) between 1929 and 1940. They were highly successful and improved service and journey times on the CPR's transcontinental routes. The third and later batches of CPR Hudsons, H1c to H1e numbers 2820 to 2864, were dubbed Royal Hudsons and were semi-streamlined. Royal permission was given for these locomotives to bear the royal crown and arms after locomotive No. 2850 hauled King George VI across Canada in 1939.
Five CPR Hudsons survived. H1b class No. 2816 Empress is the sole remaining non-streamlined CPR Hudson. It was repatriated from static display at Steamtown in Scranton, Pennsylvania, to the CPR in 1998 and was restored and converted to oil-burning to haul excursions for CPR. The other remaining H1 class locomotives are all Royal Hudsons. As of 2008, three were on display in museums, No. 2839 in California, No. 2850 in Quebec and No. 2858 in Ontario, while No. 2860, the first oil-burning Royal Hudson of the class, was operational and based in British Columbia. By 2008, the CPR Hudsons were the only operational Hudsons in North America.
The Grand Trunk Railway (GTR) had six K2 class 4-6-4T locomotives, built in September 1914 by MLW and acquired for suburban service. Numbered 1540 to 1545 on the GTR, they were reclassified as X-10-a and renumbered 45 to 50 after being absorbed by the Canadian National Railway (CN) in 1923. Three of them are preserved, numbers GT 1541 (CN 46) and GT 1542 (CN 47) at the Steamtown National Historic Site in Scranton, Pennsylvania, and GT 1544 (CN 49) at the Canadian Railway Museum in Delson, Quebec.
North American production list
Altogether 21 railroads in North America owned 4-6-4s. Many were similar in concept to the NYC Hudsons, with 79 to 80 inches (2,007 to 2,032 mm) driving wheels, but most were a little larger than the NYC locomotives, such as the F6 and F6a classes of the Milwaukee Road, the K-5-a class of the Canadian National, the Canadian Pacific locomotives, the S-4 class of the Burlington Route, the I-5 class of the New Haven and the 1151 class of the Lackawanna. There were also the lightweights, which include the L-1 class of the Nickel Plate Road, the class D of the Maine Central and the class NR-1 of the Ferrocarriles Nacionales de México (NdeM). On these, the extra axle was used to reduce the axle load in comparison to a 4-6-2 Pacific locomotive.
Because the 4-6-4 design was really only optimally suited to express passenger trains, which were dieselized early, the Hudsons were early candidates for withdrawal and scrapping. None of the NYC locomotives survived and neither did any of the Milwaukee locomotives. Five Canadian Pacific Hudsons survive, including four Royal Hudsons and the non-streamlined Canadian Pacific 2816. Five of the Burlington Route locomotives survive, including the Aeolus. Other surviving Hudson locomotives are two each of the Santa Fe and Canadian National, and single examples from the Chesapeake and Ohio Railway, N de M and Nickel Plate Road.
North American 4-6-4 locomotives (in order of introduction)
Railroad: Qty: Class: Road numbers: Builder: Build years: Notes:
Railroad: MC (NYC)
Railroad: MC (NYC)
Railroad: MC (NYC)
Railroad: B&A (NYC)
Railroad: B&A (NYC)
Railroad: B&A (NYC)
Railroad: CCC&StL (NYC)
Railroad: CCC&StL (NYC)
The New York Central Railroad's iconic streamlined Hudson 4-6-4 steam locomotive at the New York Worlds' Fair. Library of Congress.
Classic Streamliners - TRAINCYCLOPEDIA
Diagram of the 4-6-4 Wheel Arrangement: two leading wheels, three large driving wheels joined together with a coupling rod, and two small trailing wheels.
Non-streamlined NYC Hudson No. 5249.
Text: wikipedia.org. Images: Public Domain; http://www.commons.wikimedia.org (unless otherwise specified) and 17 U.S. Code § 107 fair use. References: Lewis, Robert G. The Handbook of American Railroads. New York: Simmons-Boardman Publishing Corporation, 1951, 2nd Edition 1956. Site Map Contact webmaster HERE.
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