High Quality Content by WIKIPEDIA articles! The LSWR N15 class was a British 2–cylinder 4-6-0 express passenger steam locomotive designed by Robert W. Urie. The class has a complex build history spanning three sub-classes and eight years of construction from 1919 to 1926. The first batch of the class was constructed for the London and South Western Railway (LSWR), where they hauled heavy express trains to the south coast ports and further west to Exeter.