NCC Class U2

Class U2 was numerically the largest class of locomotives on the NCC, only being equalled when the last of the Class WT 2-6-4 tank engines was delivered in 1950. The first of the class was built in 1924 and construction continued over the following thirteen years until the last engine was outshopped in 1937.

The Class U2 engines can be divided into four sub classes as follows:

• 7 New engines built by the North British Locomotive Company, Glasgow
• 3 New engines built by the NCC at York Road works, Belfast
• 4 Renewals of Class A engines
• 4 Rebuilds of Class U engines

The renewals were an accounting device to avoid the capital charges associated with building new engines; it is unlikely that much of the original engines was incorporated into the resulting U2s.

The engines were simples, i.e. not compound, with two 19 in × 24 in (483 mm × 610 mm) inside cylinders. Their boilers were rated at 170 pounds per square inch (1.17 MPa) and were fitted with Schmidt superheaters. All eighteen engines, though differing slightly in appearance had, until 1945, the same power output. The only dimensional difference was caused by six boilers, identical with the others, except that the opportunity had been taken for the first time with a Derby boiler to use the broader Irish gauge to full advantage for a wider firebox. The first two of these G7S boilers were fitted to Class A "Heavy Compounds" Nos.67 and 59 when they were renewed as Class U2 in 1934.

Two years later, four more of this type of boiler were ordered when No.87 was constructed out of Class A No.63 and Nos.72 and 73 were rebuilt from Class U to U2. The remaining boiler was presumably to have a been a spare one to enable speed shopping of engines but in the event it was immediately fitted to No.78. This engine was the last of the NBL engines to be built in 1924 but she had run a considerably greater mileage (442,681 miles or 712,430 kilometres) than other members of the class by the time she received the new boiler in October 1936.

No.70 did not have its footplate altered when it was rebuilt from Class U to U2; the short footplate made it unpopular with locomotive crews as the cab became very warm in summer and the position of some of the controls, especially the reversing lever, was cramped. It had the same nominal weight, 51 long tons 10 cwt (115,400 lb or 52.3 t), as the rest of the class,

The new locomotives were supplied with Fowler-type flush-sided tenders with a capacity of 5 tons of coal and 2,500 imperial gallons (11,000 l; 3,000 US gal) of water. The rebuilt locomotives were coupled to the original BNCR-type six-wheeled tenders which could carry 6 tons of coal and 2,690 imperial gallons (12,200 l; 3,230 US gal) of water.

Apart from a slight difference in the cab, the superb external finish of the NBL engines appears to have given them an advantage in prestige among the crews over the three Belfast-built engines. Although less than half of the class had been built in Glasgow, the U2s gained the general nickname of "Scotch Engines".

Eleven of the engines were named after Ulster castles and a twelfth, No.87, carried the name Queen Alexandra.

The U2s provided the top-link workings on the NCC until the arrival of the Class W Moguls in 1933. The fastest timing for the Portrush expresses that the U2s worked in 1932 was 82 minutes for the 58.3 miles (93.8 km) from Greenisland to Portrush, over half of the route being over a single line. They also worked the Larne Harbour boat trains, being allowed 30 minutes for the 24⅓ miles, again over a route with a significant proportion of single track.

While most of the class were based at Belfast, Nos.70, 73 and 80 were at one time assigned to Larne shed and Nos.74 and 81 were at Coleraine. In later years, No.77 was also based at Coleraine and would be one of the last engines to work a train over the Derry Central line before it closed.

The U2s performed sterling service during the busiest years of World War II. A typical job was to take over a military train at Antrim that had been worked through from the GNR(I). Having hauled eight bogie coaches from Antrim to the summit of the NCC main line, a stop would be made at Ballyclare Junction to attach carriages that had arrived from Derry or Cookstown on a previous train before travelling on to Larne Harbour where it was common to see trains of twelve or more bogie coaches arriving.

In 1945–1946, Nos.71 and 81 had the diameters of their cylinders reduced from 19–18 in (483–457 mm). It is possible that the cylinders fitted to No.72 came from Class U1 engine No.3 which had just been withdrawn. Originally fitted with Fowler pattern chimneys that had capuchons, some the class, such as No.76, later received a Stanier type and it was said by their crews that they never steamed as well after this alteration.

The Ulster Transport Authority (UTA) arranged a massive sale of withdrawn locomotives in January 1956 which included the first U2s to be withdrawn. These were Nos.70, 79, 82 and 83 at Carrickfergus and Nos.71 and 77 brought up from Ballymena. The remainder of the class were withdrawn over the following seven years. The last to go in June 1962 was No.74 Dunluce Castle which was destined for preservation.

Building and withdrawal data

The following table summarises the building and rebuilding history of the Class U2 locomotives:

U2 No.	Builder	Date built	Name	Orig. Class	Orig. No.	Re-No./ Date	Rebuilt as U2	Date rebuilt	Withdrawn	Notes
70	MR, Derby	Jul 1914		U	70		NCC, York Rd	Nov 1924	Jan 1956
71	MR, Derby	Jul 1914	Glenarm Castle	U	69	71 / 1923	NCC, York Rd	Mar 1927	Jan 1956
72	MR, Derby	Dec 1922		U	14	72 / 1923	NCC, York Rd	Feb 1937	Dec 1961
73	MR, Derby	Dec 1922		U	15	73 / 1923	NCC, York Rd	Dec 1937	Jun 1956
74	NBL, Glasgow	Jul 1924	Dunluce Castle						Jun 1962	Preserved
75	NBL, Glasgow	Jul 1924	Antrim Castle						Jun 1956
76	NBL, Glasgow	Jul 1924	Olderfleet Castle						Sep 1959
77	NBL, Glasgow	Jul 1924							Jan 1956
78	NBL, Glasgow	Jul 1924	Chichester Castle						Mar 1960
79	NCC, York Rd	Aug 1925	Kenbaan Castle						Jan 1956
80	NCC, York Rd	Nov 1925	Dunseverick Castle						Dec 1961
81	NCC, York Rd	Dec 1925	Carrickfergus Castle						Aug 1957
82	NBL, Glasgow	May 1925	Dunananie Castle						Jan 1956
83	NBL, Glasgow	May 1925	Carra Castle						Jan 1956
84	NCC, York Rd	May 1905	Lissanoure Castle	A	20	as renewed	NCC, York Rd	Dec 1929	Dec 1961
85	MR, Derby	Jun 1908		A	67	as renewed	NCC, York Rd	May 1934	Mar 1960
86	NCC, York Rd	Aug 1906		A	59	as renewed	NCC, York Rd	Sep 1934	Mar 1960
87	MR, Derby	May 1905	Queen Alexandra*	A	63	as renewed	NCC, York Rd	May 1936	Aug 1957

• The name Queen Alexandra was transferred from Class A No.34 to No.63 in November 1932.

Preserved.

No.74 Dunluce Castle was restored to LMS (NCC) livery at the UTA's Duncrue Street workshops during late 1962 and in April 1963 was transferred to the Belfast Transport Museum. This locomotive is the only preserved NCC tender engine and can now be seen in the Ulster Folk and Transport Museum, Cultra, Holywood, Co. Down. BT18 0EU.

• Arnold, R.M. (1973). NCC Saga. Newton Abbot: David & Charles. ISBN 0-7153-5644-5.
• Arnold, R.M. (1973). Supplement to NCC Saga. Whitehead: Railway Preservation Society of Ireland.
• Ellis, Hamilton (1970). London Midland & Scottish, A Railway in Retrospect. Shepperton: Ian Allan Ltd. ISBN 0-7110-0048-4.
• London Midland and Scottish Railway (Northern Counties Committee). Class U2 Nos.74,75,76,77,78,79,80,81,82,83 general arrangement drawing. Belfast: LMS (NCC). [New engines]
• London Midland and Scottish Railway (Northern Counties Committee). Class U2 Nos.70,71,72,73,84,85,86,87 general arrangement drawing. Belfast: LMS (NCC). [Rebuilt engines]
• Morton R.G. (1962). Standard Gauge Railways in the North of Ireland. Belfast: Belfast Museum and Art Gallery.