ninety vehicles. Engines At present O&K Nos. 1 and 3 are the operational steam locomotives. 1875-built 0-6-0 tank engine, GSWR No.90, delivered to Downpatrick on Sunday 30 September 2007, is Ireland's oldest steam engine capable of operation. Two E Class diesels, Nos. E421 and E432, were acquired in 1986, with E421 working the Society's first passenger trains. However, the E Class could not start from cold and thus three G Class diesels arrived at the railway to facilitate shunting and works trains - one was purchased privately by a volunteer from Westrail, and two are on long-term loan from the Irish Traction Group (ITG). The ITG also loans three mainline diesels to the railway - CIÉ A class No.A39R (arrived 22 November 2009), 141 class No. 146 (arrived 27 November 2010) and 201 Class No. C231. (arrived 7 June 2014). Railcars Sligo, Leitrim and Northern Counties Railway Railcar B, built in 1947, was donated to the railway by Iarnród Éireann in 2006. This railcar arrived in poor condition and it will be some time before the DCDR can return it to operational condition. Prototype BR-Leyland railbus, RB3, which was modified in the early 1980s to run on Irish metals and was used for a period by Northern Ireland Railways, was acquired by DCDR in 2001, with the hope of using it to run midweek trains as it did not require as large a crew as locomotive-hauled trains. However, due to several faults inherent with the prototype Railbus' design, this did not come to fruition. Three more ex-NIR railcars are owned by DCDR, comprising the last 450 Class, 458 ''Antrim Castle'', which arrived in 2014 and has been converted to a buffet train, and two 80 class railcars which arrived in 2018. Carriages There are four main 'carriage rakes'. These are: Old Buffet: Conventional 1950s carriages formerly used as the buffet train and Santa's Grotto during the Autumn and Winter months. Shown in pink on the tables below. New Buffet: A 450 Class railcar and DBSO used as the buffet train during the Spring and Summer months. Shown in blue on the tables below. Everyday Running Set: 1950s carriages used during most running days. Shown in green on the tables below. Vintage Running Set: Antique carriages (Edwardian period or earlier) normally on display in the Carriage Gallery, but brought into service for special events. Shown in brown on the table below.