British Rail Class 15

Infobox Locomotive
name = BTH Type 1
British Rail Class 15
powertype = Diesel-electric


caption = Sole surviving Class 15 no D8233 seen at Baron Street Loco Shed, East Lancashire Railway, February 2006
roadnumber = D8200–D8243
totalproduction = 44
builder = British Thomson-Houston at Clayton Equipment Company
builddate = 1957–1961
gauge = RailGauge|ussg|lk=on|al=on
primemover = Paxman 16YHXL
transmission = DC generator, DC traction motors
generator = BTH RTB10858
tractionmotors = BTH 137AZ, 4 off
whytetype = Bo-Bo
uicclass = Bo'Bo'
wheeldiameter = convert|3|ft|3+1/2|in|m|3|abbr=on
minimumcurve = convert|3.5|chain|m|lk=in
trainbrakes = Vacuum
locobrakeforce = convert|31|LTf|kN|abbr=on|lk=in
wheelbase = convert|31|ft|0|in|m|2|abbr=on
length = convert|42|ft|0|in|m|2|abbr=on
width = convert|9|ft|2|in|m|2|abbr=on
height = convert|12|ft|6|in|m|2|abbr=on
weight = convert|69|LT|sigfig=3|lk=on
topspeed = convert|60|mph|0|abbr=on|lk=on
poweroutput = "Engine:" convert|800|hp|0|abbr=on|lk=on
"At rail:" convert|627|hp|abbr=on
tractiveeffort = "Maximum:" convert|37500|lbf|kN|1|abbr=on|lk=on
fuelc
convert|400|impgal|abbr=on|lk=on
trainheating =
multipleworking = ★ Blue Star
axleloadclass = RA 4
railroad = British Railways
retiredate = 1968–1971The British Rail Class 15 diesel locomotives, also known as the BTH Type 1, were designed by British Thomson-Houston, and built by the Yorkshire Engine Company and the Clayton Equipment Company, between 1957 and 1961.

Design History

Following the British Railways Modernisation Plan, ten of the class were ordered for evaluation under the 'pilot scheme'. Like other locomotives designed to the 'Type 1' specification, they were intended for use on local freight and empty coaching stock trains. The design and manufacture was a collaboration between several companies. BTH (the main contractor) provided electrical equipment, Paxman supplied the power units, and Clayton supplied bogies and superstructure, with the frame construction and final assembly taking place at Yorkshire Engine's Sheffield works. These ten locomotives, numbered D8200–D8209, entered service between November 1957 and November 1958.

The design showed sufficient promise for a repeat order for 34 more locomotives to be placed soon afterwards. These locomotives, numbered D8210–D8243 and built by Clayton at Hatton, Derbyshire, were delivered between October 1959 and February 1961.

Technical

* Engine: Paxman 16YHXL
* Cylinder bore: 7 in (178 mm)
* Piston stroke: 7¾ in (197 mm)
* Traction motors: 4 x BTH 137BZ, nose suspended, with single reduction gear drive
* Main Generator: BTH RTB10858
* Auxiliary Generator: BTH RTB7420

Working Life

The first ten locomotives were delivered to the London Midland Region's Devons Road depot in Bow, East London, where they were evaluated against the contemporary North British Type 1 and English Electric Type 1 designs. Soon, however, the entire class was allocated to depots on the Eastern Region, where they remained until withdrawal. The second block of ten was originally allocated to March depot in East Anglia, however due to the Clean Air Act 1956 the locomotives were quickly re-allocated to East London, allowing the replacement of steam locomotives in that area. Thereafter, the type was allocated exclusively to Stratford, Finsbury Park and Ipswich depots.

The class were troubled by several reliability problems, notably with the engines which were found to require excessive maintenance. The layout, with a single cab positioned part-way down the body like a North American road-switcher, gave the crew poor forward visibility in both directions of travel, although this was initially tolerated as it was no worse than the visibility from a steam locomotive cab. Despite these problems the class were more successful than the contemporary Type 1 locomotives of Class 16 and the later Class 17.

With a decline in freight duties in the London area, and as a relatively small and non-standard class, the type was considered surplus to requirements by the late 1960s. All were withdrawn from capital stock between April 1968 and March 1971. All but four had been broken up for scrap by the end of 1972.

A Reprive

The four that survived were converted into non-powered electric train pre-heating units at Doncaster Works, these duties keeping the locomotives employed for another ten years, until they were again made redundant and withdrawn.

Preservation

One of the former train heating units, D8233, was purchased for preservation in 1984 and is now the only survivor of the type. It was originally kept at the South Yorkshire Railway in Sheffield, moving in 1986 to the East Lancashire Railway, and in 1988 to the Mangapps Farm Railway, where it remained until 1993. D8233 then moved to Crewe following an agreement with the Waterman Heritage Trust. Since its initial preservation the locomotive had received little work apart from cosmetic attention. Some work was carried out by the Waterman Heritage Trust, however the locomotive's restoration remained dormant until the end of 2005, when a reformed owning group, alongside the WHT, agreed the time was right to accelerate the locomotive's return to service. With an active plan for work agreed, the locomotive returned to the East Lancashire Railway in February 2006, where its restoration to working order is now underway.

Models

To date, no ready-to-run models of the Class 15 have been produced. However, Heljan have announced plans for a OO gauge ready-to-run model.

References and Sources

References

Reflist

ources

*cite book | last = Stevens-Stratten | first = S.W. | coauthors = Carter, R.S. | title = British Rail Main-Line Diesels | publisher = Ian Allen Ltd | date = 1978 | location = Shepperton | isbn = 0 7110 0617 2
*cite book | last = Williams | first = Alan | coauthors = Percival, David | title = British Railways Locomotives and Multiple Units including Preserved Locomotives 1977 | publisher = Ian Allen Ltd | date = 1977 | location = Shepperton | isbn = 0 7110 0751 9
*cite book | title = British Railways Locoshed Book 1977| publisher = Ian Allen Ltd | location = Shepperton | isbn = 0 7110 0752 7
*cite book | last = Sugden | first = S.A. | title = Diesel & Electric Loco Register (3rd edn) | publisher = Platform 5 | location = Sheffield | isbn = 1 872524 55 9
*cite book | last = Grindlay | first = Jim | title = British Railways Locomotive Allocations 1948-1968 (Part 6 - Diesel & Electric Locomotives) | publisher = Modelmaster Publications | location = Troon | isbn = 978 0 9544264 6 0

External links

* [http://www.d8233.org.uk Class 15 Preservation Society, Owners of sole surviving Class 15, D8233]