LSWR G16 Class

The LSWR G16 Class was a series of four outside-cylinder 4-8-0 heavy shunting tank locomotives designed by Robert Urie and built at Eastleigh Works in 1921, specifically constructed for hump shunting duties at the newly built Feltham marshalling yard in west London — one of the largest and most modern freight marshalling yards in Britain at the time of its construction. The G16 Class was unusual in British railway practice for the 4-8-0T wheel arrangement, with eight coupled driving wheels giving the maximum adhesion required for pushing heavy rakes of wagons up the hump at Feltham against considerable resistance.

Feltham marshalling yard had been built by the LSWR in 1920–21 as a central sorting facility for the railway's freight traffic, using the gravity hump shunting method in which wagons were pushed over a hump and rolled down into their appropriate sorting sidings under gravity with minimal locomotive effort. The hump locomotive's task was specifically to push the rakes of loaded wagons up the hump at a controlled, slow speed, requiring enormous tractive effort at very low speeds rather than the sustained running demanded of main-line locomotives. For this duty the eight coupled wheels of the 4-8-0T gave unmatched adhesion.

Urie designed the G16 with outside cylinders and his characteristic Eastleigh features — stovepipe chimney, prominent outside steam pipes, and the austere but functional appearance that distinguished his designs from the more elaborately finished Adams and Drummond locomotives. All four G16s remained at Feltham essentially throughout their working lives, serving the Southern Railway and then British Railways on hump shunting duties until the late 1950s. None was preserved, though the G16 Class represents a fascinating and highly specialised corner of British locomotive engineering seldom encountered outside the history of marshalling yard operation.