GWR Sir Daniel Class

The GWR Sir Daniel Class was a series of inside-cylinder 2-2-2 express passenger locomotives designed by Daniel Gooch and built at Swindon Works from 1851, representing a standard-gauge single-driver express type alongside the GWR's celebrated broad-gauge Iron Duke and Rover classes. While the broad-gauge fleet had the advantage of 8 ft driving wheels impossible on standard gauge, the Sir Daniel Class demonstrated that Gooch could produce capable standard-gauge single-driver express locomotives with driving wheels of 7 ft — the maximum practical on the narrower track — that gave respectable performance on the GWR's growing standard-gauge secondary routes.

The GWR was operating both broad gauge and standard gauge in this period, the latter on the secondary and absorbed lines that could not be practically converted to broad gauge. The Sir Daniel Class provided standard-gauge express capability for these routes, giving the GWR a single-driver express type that, while naturally less impressive than the broad-gauge Rover Class contemporaries, was competitive with the standard-gauge express locomotives of other railways.

The Sir Daniel Class worked standard-gauge express services on the GWR's secondary main lines through the 1850s and 1860s, before being superseded by Joseph Armstrong's more modern designs. None was preserved.