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].
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| 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.
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| D8568 in BR blue livery at Kidderminster Town | 
| D8568 at Bewdley | 
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| 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