BCDR 4-6-4T

At the end of the First World War the BCDR directories decided they would like some more powerful locomotives, and were impressed by the LB&SCR L class 4-8-4T "Brighton Baltics" on the London to Brighton line, and Petterson considered a requirement to procure a similar type imposed upon locomotive superintendent R. G. Miller.[2] When the locomotives arrived in 1920 from Beyer Peacock they were inherited by Miller's successor Crossthwait. The BCDR locomotives had smaller dimensions: 19x26in cylinders as opposed to 21x28in; driving wheels 5 ft 9&nbspin[lower-alpha 1] as opposed to 6 ft 9&nbspin.[2] At oven 81 tons the locomotives were noted for being very heavy.[2] They were the only locomotives of the 4-6-4 in Ireland apart from two on the narrow gauge Londonderry and Lough Swilly Railway.[2]

Allocated the numbers 22 to 25 they were to be allocated to heavy commuter trains on the 12+1⁄4 miles (19.7 km) Belfast Queen's Quay to Bangor line.[5][lower-alpha 2] In service the class was reliable but performance was mediocre and coal consumption was very high.[2] Boocock has described them as "handsome" and "well-liked" and suggests the problem may have been due to short-travel piston valves rather than drafting.[7]

The BCDR was absorbed into the Ulster Transport Authority (UTA) on 3 September 1948, the class being renumbered 222 to 225.[8][3] Class WT 2-6-4T were transferred to the Bangor line from summer 1949 and their performance was substantially better, and they began to replace the BCDR engines,[9] with UTA MED diesel railcars, the Bangor line losing all steam working by 1953.[10] Only one worked past 1952,[3] No. 222 surviving[lower-alpha 3] on the former Northern Counties Committee network with the remainder lying withdrawn at Queen's Quay sidings.[9] All were disposed for scrap in 1956.[9]