Franco-Crosti boilered 9F 2-10-0 No 92021 with a Toton to Brent coal train seen approaching Elstree & Brehamwood on the fast line, October 1, 1955.
Peter Kerslake says "The Second Standard "9F" introduced in 1955 with the Franco Crosti boiler not long having entered service and allocated to Wellingborough depot in company with the other nine of the sub-class. Intended to burn poor quality coal the ten engines experienced problems with smoke and fumes entering the footplate, together with additional maintenance requirements . This resulted in their conversion to the more conventional design with effect from September 1959, beginning with 92026, the conversion programme taking three years to complete."
Photo: K.L. Cook/Rail Archive Stephenson