British Rail Class 27

BRCW Type 2 British Rail Class 27
27001 at Bo’ness
Power type	Diesel-electric
Builder	Birmingham Railway Carriage and Wagon Company
Serial number	DEL190–DEL258
Build date	1961–1962
Total produced	69
Configuration	Bo-Bo
UIC classification	Bo'Bo'
Gauge	4 ft 8 1⁄2 in (1,435 mm) Standard gauge
Wheel diameter	3 ft 7 in (1.092 m)
Minimum curve	5 chains (100 m)
Wheelbase	39 ft 0 in (11.89 m)
Length	50 ft 9 in (15.47 m)
Width	8 ft 10 in (2.69 m)
Height	12 ft 8 in (3.86 m)
Locomotive weight	Originally: 72.50 long tons (73.7 t) 71-76 tonnes
Fuel capacity	685 imp gal (3,110 l; 823 US gal)
Prime mover	Sulzer 6LDA28-B
Traction motors	four GEC WT459 traction motors
Transmission	DC generator, DC traction motors
Multiple working	★ Blue Star
Top speed	90 mph (145 km/h)
Power output	Engine: 1,250 hp (932 kW) @750 rpm At rail: 933 horsepower (696 kW)
Tractive effort	Maximum: 42,000 lbf (187 kN) Continuous: 25,000 lbf (111 kN)
Train heating	As built, Steam generator subclass 27/2, Electric Train Heating, Houchin 120 kW alternator powered by Deutz 8-cylinder air-cooled diesel engine, type F8L413
Locomotive brakeforce	34 LTf (340 kN)
Train brakes	Vacuum, some later dual Air & Vacuum
Career	British Railways
Number	D5347–D5415; later 27001–27066
Axle load class	Route availability 6 (RA 5 from 1969)
First run	1961

British Rail's Class 27 comprised 69 diesel locomotives built by the Birmingham Railway Carriage and Wagon Company (BRCW) during 1961 and 1962. They were a development of the earlier Class 26; both were originally classified as the BRCW Type 2.

Usage

Original allocations were D5347 - 5369 to Glasgow Eastfield, D5370 - 5378 to Thornaby and D5379 - 5415 to London Cricklewood for Tilbury Boat trains and Cross-London freight services. In the period September to December 1963, some of the Cricklewood allocation were transferred to Leicester and in December 1965 the Thornaby allocation was also nominally transferred to Leicester to join them. Traffic changes combined with reallocation of class 25 led to the gradual transfer of the Leicester and Cricklewood locomotives to Scotland during 1969 thus concentrating the whole class within Scotland and being part of the replacement fleet that allowed the withdrawal of the poorly performing Clayton Class 17 locomotives from traffic. For many years they were extensively used on the West Highland Line. The last locomotives were withdrawn from service in 1987, being outlived by the older Class 26s, whose less powerful engines were more reliable.

Edinburgh-Glasgow

By the late 1960s, the Swindon-built Inter City DMUs operating the Edinburgh Waverley - Glasgow Queen Street express service were becoming unreliable. These trainsets are incorrectly described as Class 126 but the individual vehicles are numbered in the 79xxx series thus were never allotted a BR TOPS classification. Class 126 units are Swindon's later build of 3-car trainsets numbered in the 51xxx/59xxx/51xxx series allocated to Glasgow St Enoch (later Glasgow Central) - Ayrshire and Stranraer services. They were replaced in 1971 by specially adapted Class 27s fitted with push-pull equipment to “top and tail” rakes of six Mark 2 carriages which were specially fitted with air operated disc brakes. At one end would be a Class 27/1, at the other a Class 27/2 (which provided train heating). The very intensive 90 mph (140 km/h) “push-pull” service was demanding on the locomotives and reliability started to suffer. The 27/2s, especially, appeared prone to fire damage, especially from their electric train heating alternators. The push-pull sets were replaced in 1980 by single Class 47/7s at one end of a rake of Mark 3 carriages and a DBSO. The spare Class 27/1s were then transferred for use on Edinburgh-Dundee semi-fast passenger services, until their replacement by Class 150 Sprinter DMUs in 1987, whilst the 27/2 subclass was largely used on freight. Their ETH supply was no longer used.

Preserved locomotives

Eight examples of the class have been preserved at various heritage railways in Great Britain.

Numbers (current in bold)				Livery	Location
D5347	27001			BR Blue	Bo'ness and Kinneil Railway
D5351	27005			BR Blue	Bo'ness and Kinneil Railway
D5353	27007			BR Green	Mid-Hants Railway
D5370	27024			BR Green (Yellow Warning Panels)	Lakeside and Haverthwaite Railway
D5394	27050	27106	5394	BR Blue	Strathspey Railway
D5401	27056	27112		BR Green	Great Central Railway
D5410	27059	27123	27205	BR Green	Severn Valley Railway
D5386	27066	27103	27212	BR Blue	Dean Forest Railway

27066 on the Dean Forest Railway

D5401 (27056) at the Great Central Railway

References

Literature

• Harris, Roger (2nd Edition 1985). The Allocation History of BR Diesels and Electrics. Bromsgrove: Roger Harris. 
• Marsden, Colin J. (1981). Motive power recognition:1 Locomotives. Shepperton: Ian Allan Ltd. ISBN 0 7110 1109 5. 
• Oakley, Michael (1981). BR Class 26/27 Diesels. Truro: D Bradford Barton. ISBN 0 85153 418 X. 
• Tayler, A.T.H (1984). BR Locomotives:2 Sulzer Types 2 and 3. Ian Allan Ltd. ISBN 0 7110 1340 3. 
• Williams, Alan; Percival, David (1977). British Railways Locomotives and Multiple Units including Preserved Locomotives 1977. Shepperton: Ian Allan Ltd. ISBN 0 7110 0751 9. 
• Ian Allan ABC of British Railways Locomotives, 1983 edition

External links

• Scottish Railway Preservation Society home to 27001 and 27005
• Mid Hants Railway home to 27007
• Caledonian Railway Diesel Group, owners of 27024
• Owners of 27056 based at the Great Central Railway
• Severn Valley Railway home to 27059
• Owners of 27066 based at the Dean Forest Railway