Overview
The GWR had favoured pannier tank locomotives since 1911 when they had started rebuilding saddle tank locomotives built between 1870 and 1905 into this style. By 1929 these older locomotives were in need of replacement.
The first 5700s were almost identical in appearance to several of the older converted locos (e.g. classes 645, 1701, 1854, 2721) and had round spectacles (windows) in the cab front, but those built after 1933 from no. 8750 onwards had rectangular windows and a slightly different cab profile virtually identical to the style introduced with the 5400 Class in 1931. Whilst they can be viewed as a simple update of the 2721 Class, the Collett improvements were worthwhile and the class became as synonymous with the GWR as Castles and Kings, lasting until the end of steam on the Western Region of British Railways.
The size of the class demanded that the 5700 class locomotives were spread across several series of numbers.
- 3600 - 3699
- 3700 - 3799
- 4600 - 4699
- 5700 - 5799
- 6700 - 6779
- 7700 - 7799
- 8700 - 8799
- 9600 - 9682
- 9701 - 9799
Most were built at Swindon Works, but about 25% were built by private builders:-
- Armstrong Whitworth – 7775–7799 (25)
- W. G. Bagnall – 6700–6724, 8725–8749, 8400–8449 (100)
- Beyer, Peacock & Co. – 8700–8724 (25)
- Kerr Stuart - 7700–7724 (25)
- North British – 5700–5749, 7725–7749 (75)
- Yorkshire Engine Co. – 6725–6749 (25)
Read more about this topic: GWR 5700 Class