to operate on major railroads in the United States were the 2-8-8-2 Y6b class of the Norfolk and Western Railway. After their final modifications in the 1950s, they were said to be capable of 170,000 lbs tractive effort in simple-expansion mode, although some have questioned this claim (the original design tractive effort was 152,206 lbs SIMPLE and 126,838 lbs COMPOUND). The last were retired in May 1960. As of 2008, there are two surviving 2-8-8-2 locomotives, both former Norfolk & Western. N&W 2050 is from the railroad's Y3a class; Alco's Richmond works built it in 1923 and it is displayed at the Illinois Railway Museum in Union, Illinois. N&W 2156, the strongest pulling extant steam locomotive in the world, is from the railroad's Y6a class; N&W's own Roanoke Shops built it in 1942 and it is owned by the National Museum of Transportation in St. Louis, Missouri. The 2156 was displayed at the Virginia Museum of Transportation in Roanoke, Virginia from 2015 to 2020. As of June 2020, it has returned to the Museum of Transportation in St. Louis. See also USRA 2-8-8-2 References External links builder's photo of N&W 2156, Virginia Tech collection picture of N&W 2156 in 1985 picture of N&W 2156 in 2007 Web Site of ToyTrains1 2-8-8-2 Articulated Steam Locomotives 88,2-8-8-2 Mallet locomotives