2-8-0 "Consolidation" Steam Locomotives in the USA

Class 551 (Locobase 16706)

Data from

Standard Consolidation built by Alco, Baldwin , and Lima for the US Army's Transportation Corps in World War II. See also Bob Lettenberger, "No. 557 fired up after 60 years", Trains Magazine, February 2026, pp. 44-45 and Engine 557 Restoration Company on the web at [], last accessed 16 January 2026. Baldwin's works numbers were 69636-69639, 69854-69855 in 1943 and 70480, 70478-70479, 70367, 70366, 70431 in 1944.

See Locobase 433 for a great deal of commentary on the S160 Consolidation design of which several builders turned out more than 2,000 during World War II Beginning in 1943, twelve were diverted from the US Army Transportation Corps roster to meet the Alaska Railroad's motive power needs. (The railroad had hoped for more 4-8-2s, but wartime production constraints dictated a resort to these smaller, but readily available locomotives.) They joined the slightly larger Lima-built sextet (Locobase 6426).

Little changed from the USATC spec, the engines used 10" (254 mm) piston valves, a generously scaled superheater, had three American Security arch tubes in the firebox and a Hulson rocking grate, but otherwise was a relatively austere, straightforward design.

Four arrived almost immediately, two more followed by the end of 1943. With the arrival of the 557 in late 1944, the Alaska had bought its last new steam locomotive. The ARR later obtained 558-562, which the US Army had never run, as war surplus. The class worked most kinds of service from freight to passenger traffic.

553 suffered a career-ending wreck in 1943 (i.e., not long after it entered service on the ARR). By the latter part of the 1950s, the ARR started phasing out the 551s by retiring 555 and 560 in April 1954. 551, 556, 561-562 left the roster in January 1956. Spanish mineral railway FC de Langero bought six of the engines (555, 560, 552, 554, 558, and 559) in January 1958.

557 handled the last steam-powered train in September 1959, after which it lay idle until bought in 1965 for display in a private museum in Everett, WA. Upon its return to Alaska in 2012, a group formed the Engine 557 Restoration Co and began reconditioning it to operate it. The lastest milestone was reached on 8 November 2025 when the team steamed up the boiler and found it fit.