Norfolk and Western A class
Norfolk & Western No. 1206 at the New York World's Fair on June 17, 1939
Type and origin Power type Steam Builder N&W's Roanoke Shops Serial number 266–267, 273–280, 332–346, 353–362, 380–387 Build date 1936–1950 Total produced 43
Specifications Configuration: ​  • Whyte 2-6-6-4  • UIC (1′C)C2′ h4g Gauge 4 ft 8+1⁄2 in (1,435 mm) standard gauge Leading dia. 33 in (838 mm) Driver dia. 70 in (1,778 mm) Trailing dia. 42 in (1,067 mm) Wheelbase Loco & tender: 108.27 ft (33.00 m) Length 121 ft 9+1⁄4 in (37.1 m) including tender[1] Width 11 ft (3.35 m) Height 15 ft 10 in (4.83 m) Axle load 72,000 lb (33,000 kilograms; 33 metric tons) Adhesive weight 433,350 lb (196,560 kilograms; 196.56 metric tons) Loco weight 573,000 lb (260,000 kilograms; 260 metric tons) Tender weight 378,600 lb (171,700 kilograms; 171.7 metric tons) Total weight 951,600 lb (431,600 kilograms; 431.6 metric tons) Fuel type Coal Fuel capacity 30 short tons (27 t) Water cap. 22,000 US gal (83,000 L; 18,000 imp gal) Fuel consumption 7 short tons (6.4 t) of coal per hour 13,906 US gal (52,640 L; 11,579 imp gal) of water per hour Firebox: ​  • Grate area 122 sq ft (11.3 m2) Boiler 106 in (2,692 mm) Boiler pressure 300 lbf/in2 (2.07 MPa) Heating surface: ​  • Firebox 587 sq ft (54.5 m2) Superheater: ​  • Type Type E  • Heating area 2,703 sq ft (251.1 m2) Cylinders Four Cylinder size 24 in × 30 in (610 mm × 762 mm) Valve gear Baker
Performance figures Maximum speed Over 70 mph (110 km/h)[1] Power output 5,400 hp (4,030 kW) Tractive effort 114,000 lbf (507.10 kN)[1] Factor of adh. 3.8
Career Operators Norfolk and Western Class A Numbers 1200–1242 Retired 1958–1959 Preserved (No. 1218) Disposition One preserved, remainder scrapped

The Norfolk and Western A was a class of 43 2-6-6-4 simple articulated steam locomotives built by the railroad's own Roanoke Shops between 1936 and 1950 and operated until the late 1950s. The locomotives hauled fast and heavy freight trains for the railroad and only one has been preserved, No. 1218.

Upon delivery on the class starting in 1936, starting with 1200 and 1201, they were tested and proved successful. The railroad was satisfied with the class and bought eight more the following year. During testing, N&W officials were very impressed with their performance, as they were capable of pulling 4,800 tons at 25 mph on a 0.5% grade and 7,500 tons at 64 mph on level track. During World War II, the railroad built 25 more "A"s between 1943 and 1944 and finally eight more between 1949 and 1950. They were some of the last mainline steam locomotives to be put into service.^[2]

The locomotives had a cast-steel frame and Timken roller bearings on nearly every surface. The last five had McGill MultiRol roller bearings in the side and main rods, making them the only articulateds to take such friction-reducing measures. They were assigned to freight service and have pulled slower heavy freight trains as well as fast time freight. They were rated at 13,000 tons of drag freight between Williamson, West Virginia and Portsmouth, Ohio, and could reach speeds up to 42 mph pulling such a load. Between Portsmouth and Columbus, Ohio, they were rated at 5,200 tons of fast freight and could reach 65 mph. On passenger runs, they could reach 70 mph. Over the Kenova District, the railroad increased the "A"'s slow freight tonnage ratings from 13,000 to 14,500 tons. To reduce the amount of stops for water, they ran with auxiliary tenders with capacities of up to 20,800 gallons of water. This also increased gross ton-miles per train hour (GTM) 31% on the 112-mile Kenova District between Williamson and Portsmouth, Ohio.

In 1952, the N&W tested one of the "A"s 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, diesels eventually won out for lower maintenance and other operational costs. As successful as the class was, diesels eventually replaced them. Retirement started in 1958 and by 1959, all of the "A"s had been retired.^[3]

Only one "A" class has been preserved, No. 1218. It was retired in 1959 and on the same year, it was purchased by the Union Carbide Co. in Charleston, West Virginia, where it was used as a stationary boiler at a chemical plant.^[4] In 1965, it was repurchased by New England millionaire F. Nelson Blount for his locomotive collection at Steamtown, U.S.A. in Bellows Falls, Vermont.^[4] Three years later, its former owner Norfolk & Western did a cosmetic restoration on 1218 at their East End Shops in Roanoke, Virginia (the same place where it was built).^[4] After that, it was put on display at the Roanoke Transportation Museum in 1971.^[4] It was restored and operated in excursion service for the Norfolk Southern steam program between 1987 and 1991 and went for an overhaul. The program was then canceled in 1994 and the locomotive was eventually put back on display at the Virginia Museum of Transportation in Roanoke, Virginia. It is the only surviving 2-6-6-4 steam locomotive in the world.

• King, Ed (1991). The A: Norfolk & Western's Mercedes of Steam First Edition (1st ed.). Trans-Anglo Books. ISBN 0-870460-96-X.
• Wrinn, Jim (2000). Steam's Camelot: Southern and Norfolk Southern Excursions in Color (1st ed.). TLC Publishing. ISBN 1-883089-56-5.