British Diesels and Electrics: September 2023

Class 124 (BR Swindon Trans-Pennine 6-car)

The Class 124 was the most distinctive looking example of first generation diesel multiple unit built for British Rail. The class of 6-car (initially) units had large cab windows unlike any other DMUs though mechanically did share components with the Class 123 and 126. They were introduced into service in the early 1960s and used exclusively on trans-Pennine services where they reduced journey times by up to forty-five minutes.

In original configuration [2]

Information
Number built:	51 (8 6-car sets plus 3 spares)
Built:	1960
Builder:	BR Swindon
Motor:	2 Leyland Albion 6-cylinder diesels per power car
Power:	1, 840 hp (1, 360 kW)
Formation:	DMC (Driving Motor Composite)+MBSL (Motor Brake Standard Lavatory)+TSL (Trailer Sandard Lavatory)+TFLRB (Trailer First Lavatory Restaurant Buffet)+MBSL+DMC

In later years they often operated as 4-car units, in these cases the motors in the MBSLs were removed and they were reclassified TBS [1]. In the late 1970s they were moved to Western Region and merged with their sister class 123. They operated Reading services in 4-car hybrid units before final withdrawal in 1984. Unfortunately none were preserved.

[1] Colin J Marsden, DMUs (Ian Allan, 1982) p. 78

[2] "Trans-Pennine Diesel Sets", International Railway Journal (April 1961) p. 22

Class 17 (Clayton Equipment 900hp Type 1 Diesel-Electric)

One operational drawback with large steam locomotives is driver visibility, when the locomotive is operating smoke box first. The large boiler can make seeing signals and on-track obstacles difficult. The first batch of Type 1 diesel locomotives like the Class 15 and Class 20 shared this problem as they only had a single cab at one end. The Class 17, known as the "Clayton", was an attempt to alleviate this problem with a new standard Type 1 which had a cab sandwiched between 2 smaller and low profile diesel engines [1].

D8568 at Highley

Information
Number built:	117
Built:	1962-5
Builder:	Clayton Equipment
Engine:	2 Paxman 6ZHXL diesels (2 locos were fitted with Rolls Royce D diesels)
Power:	900 hp (672 kW)
Wheel arrangement:	Bo-Bo

As happened with a number of early British Rail diesel locomotives in the 1960s, amid a clamour to replace steam, series production was agreed and begun before much testing had taken place. In the event this was a real problem with the Class 17 as 117 of them had been built and they proved to be very unreliable. Availability of the fleet dropped to 50% (by comparison the Class 20 was about 90%) with numerous problems including cracked crankcases and oil leaks, some were put into storage straight from the factory.

As the reliability problems continued (even with a couple of examples retro-fitted with Rolls Royce engines), and the kind of light freight traffic they were designed for dropped post-Beeching, British Railways decided to withdraw them after only a few years of service. All were gone from revenue service by 1971.

No Class 17 saw ten years of BR revenue service though a couple remained in departmental service until the late 1970s [2]. One of these, D8568, survived long enough to make it into preservation.

D8568 in BR blue livery at Kidderminster Town

D8568 at Bewdley

Overhead view demonstrating the great driver position

D8568 brings a train into Chinnor

At Kidderminster Town, note how much of the loco length is taken up by the cab!

[1] Brian Haresnape, Production Diesel-Electrics Types 1-3 (Ian Allan, 1983) p. 74
[2] Colin J. Marsden, 25 Years of Railway Research (OPC, 1989) p. 79

London Underground 1960 Tube Stock

The 1960 Tube Stock was a small prototype class of stock for London Underground consisting of twelve Driving Motors (DMs). The stock ran in 4 car formations with the addition of two trailers from earlier tube trains, either Standard Stock or 1938 Tube Stock. The DMs were made from aluminium and have four motors each. Other innovations bought in by this stock included the first 300 volt motors used in service trains and the use of fluorescent instead of tungsten-filament emergency lighting.

Driving Motor [1]

Information
Number built:	12 Motor cars
Built:	1960
Builder:	Cravens
Motor:	4 LT113 motors per car (630v DC fourth rail)
Power:	480 hp (358 kW)
Formation:	Driving Motor (DM) + Trailer (T) + T + DM

The stock was introduced onto the Central Line and remained in service until 1994, though spending most of it's time on the Woodford to Hainault section of the line. The stock was used to help develop Automatic Train Operation, the first ATO equipped train entering service in 1964.

Despite the success of the 1960 Tube Stock, plans to produce 338 more cars in a production batch were abandoned due to delays and the pressing need for new stock. Instead London Underground built the 1962 Tube Stock based on the earlier 1959 Tube Stock. Features from the 1960 Tube Stock did get used by the Victoria Line's 1967 Tube Stock.

Two 1960 Tube Stock trains survive, one is used by London Underground as a Train Recording Train (with a 1973 Tube Stock trailer [2]). The other has been preserved.

Converted Trailer [1]

[1] "New prototype tube cars enter service on London Transport", International Railway Journal (January 1961) Vol.1 Issue 1 p. 28

[2] Kim Rennie, Underground and Overground Trains (Capital Transport, 2017) p. 63

Class 170 Turbostar

The Class 170 Turbostar was one of the largest fleets of new generation diesel multiple units which was built post-privatisation. The Class 170 typically operates on regional and long-distance (cross country) services and is a development of the Class 168 Clubman diesel multiple unit [1]. Indeed later built 168s and 170s have a very close resemblance (some Class 170s have been re-classified as Class 168/3s). The follow-on Turbostar DMUs Classes 171 and 172 also look near identical, meaning the Turbostar "look" is a very common one on British rails.

ScotRail 170 403 at Nairn

Information
Number built:	331 (122 2 and 3-car sets)
Built:	1998-2005
Builder:	ABB Derby / Bombardier Derby
Motor:	MTU 6R 183TD13H diesel per car
Power:	1, 266 hp (945 kW) / 844 hp (630 kW)
Formation:	Typically Driving Motor Standard Lavatory (DMSL)+Motor Standard (MS)+Driving Motor Composite Lavatory (DMCL) or DMSL+DMCL (170/3): DMCL+Motor Standard Lavatory Restaurant Buffet (MSLRB)+DMSL (170/4): DMCL+MS+DMCL

The Class 170 is used throughout the rail network, operated by ScotRail, Cross Country, Transport for Wales and East Midlands Railway. Previous operators include South West Trains [2], West Midlands Railway, Hull Trains and First TransPennine Express.