The Urie locomotives (hitherto referred as N15s rather than King Arthurs) were also given names connected with Arthurian legend and were referred to as "Urie Arthurs"; the Maunsell batches of N15s were nicknamed the "Eastleigh" and "Scotch Arthurs". Operational details The N15 class was intended to haul heavy expresses over the long LSWR mainlines between Waterloo, Weymouth, Exeter and Plymouth. Locomotives were changed at before the upgrading of the South Western Mainline in 1922, when fast running through to Exeter was possible. The Southern Railway's motive power re-organisation following the Grouping of 1923 saw the class allocated to sheds across the network and used on to cross-country trains. Operations were expanded to more restricted Central and Eastern section mainlines in 1925, and suitably modified class members hauled commuter and heavy boat trains from to and expresses to . In 1931, No. E780 Sir Persant hauled the inaugural Bournemouth Belle Pullman train from Waterloo to . In peacetime, the class was occasionally used on fast freights from Southampton Docks, although it was common to see them at the head of freight and troop trains during the Second World War. Ten "Urie Arthurs" were transferred to the London and North Eastern Railway (LNER) in October 1942, and were based at Heaton shed for use on freight and occasional passenger trains in the north east and southern Scotland. They returned to the Southern Railway in July 1943 after the introduction of United States Army Transportation Corps S160 class 2-8-0s into service. From 1945 the King Arthur class regularly deputised for Bulleid's new Pacifics, which were experiencing poor serviceability due to mechanical failures. The entire class came into British Railways ownership in 1948: they could be found in most areas of the Southern Region on medium-length expresses and stopping trains on the ex-LSWR mainline. Smoke deflector experiments In 1926 the N15 class became the first in Britain equipped with smoke deflectors, with several designs tested. Experiments were undertaken throughout 1926 and included the fitting of a curved plate above the smokebox of No. E753 Melisande to channel air from below the chimney to lift the exhaust above the locomotive when on the move. Nos. E450 Sir Kay and E753 Sir Gillemere had air scoops attached to the chimney, whilst E772 Sir Percivale was fitted with large, square German-type smoke deflectors. Finally, No. E453 King Arthur was fitted with small, rectangular smoke deflectors fitted to