Recognition and Equipment information
CLASS 15




Of the many orders placed under the Modernisation Plan pilot scheme, one was a contract to Clayton Equipment Co to build a fleet of 10 ( increased to 44) Type A (Type 1) 800hp locos for freight and branch line operation.
The fleet were powered by a Paxman 16YHXL engine driving British Thomson-Houston electrical equipment. The original order for 10 locos, allocated running numbers D8200-D8209, was made in November 1955 with building effected by the Yorkshire Engine Co in 1956-57. Subsequent orders were placed for identical machines in 1958-59 which led to a fleet of 44, running numbers for follow-on locos was D8210-D8243.
Construction of Nos. D8210-D8243 was carried out by Clayton. The first loco of the build was handed over to the BTC at Euston on November 18, 1957; after testing and proving it was allocated to Devons Road (Bow) shed and started operation around East London. However, after only a short time their operating range was extended by taking over some cross-London freights. When originally ordered this fleet was to be deployed in East Anglia, but due to London authorities demanding the implementation of the newly passed Clean Air Act, it was decided to use the fleet in London, allowing steam to be phased out from some areas.
In less than a year from introduction of No. D8200 the ten pilot order locos were all in service providing a good miles-per-casualty figure. The order for locos Nos D8210-D8243 began to appear in October 1959, with the final one taking to the rails in February 1961. The complete fleet of BTH Type 1s, as they became known, was deployed on ER London area freights and some empty stock duties, until the gradual decline in freight traffic in the late 1960s/early 1970s led to their withdrawal. Two locos soldiered on during the early 1970s for empty stock working in the Stratford-Liverpool Street area but the majority were sold for scrap. Under the BR numerical classification the fleet were Class 15, but none survived to receive their five figure TOPS numbers. When built the locos were painted in all over BR green , which was later altered to accommodate yellow warning ends.
After withdrawal from service, four locos were taken into departmental service as carriage pre-heating units. All have now been withdrawn. One Loco, No. D8233, has been saved by enthusiasts and is presently at The Railway Age, Crewe.






The pioneer loco of the build, No. D8200, viewed from the short cab end, in 'as delivered' condition. These locos were unusual in UK traction design in having a cab area slightly set in from one end and was only followed by one other production class (Class 16). CJM Collection.



Access to internal equipment on this design of locomotive with 'bonnet' sections is very easy, with a series of hinged and removable doors giving side access while the top sections of the roof over the power unit and generator were removable to allow complete extraction of the equipment. The small bonnet section is seen to house electrical and control equipment's. No. D8200 is illustrated with its No. 1 end on the left. CJM Collection.



BTH Type 1 front end layout. A-disc train reporting system, these were hinged on the horizontal axis to either show white or body colour, as will be seen by the disc bottom left, a white marker light was provided behind the bottom disc section, B-red tail light, C-vacuum brake pipe, D-through steam pipe, E-multiple control jumper socket, F-multiple control jumper cable, G-coupling, H-air control pipe, I-air control pipe. CJM Collection.