Regional airliner were replaced by progressively longer-range designs. In the immediate post-war era these were typically Douglas DC-3s, although even the De Havilland Dragon Rapide biplane airliner remained in service for some time. This "hand-me-down" process of supplying aircraft continued with designs like the Convair 440, Douglas DC-6 and Vickers Viscount also serving in this role while the first jets were introduced. By the mid-1950s, demand for even more economical designs led to the production of the first custom feederliners. These were almost always turboprops, which had fuel economy on par with piston engine designs, but had far lower maintenance costs. Often
Vickers River Tyne. Armstrongs shipbuilding interests became the "Naval Yard", those of Vickers on the west coast the "Naval Construction Yard". Armstrong Whitworth Aircraft was not absorbed by the new company. In 1928 the Aviation Department became Vickers (Aviation) Ltd and soon after acquired Supermarine, which became the "Supermarine Aviation Works (Vickers) Ltd". In 1938, both companies were re-organised as Vickers-Armstrongs (Aircraft) Ltd, although the former Supermarine and Vickers works continued to brand their products under their former names. 1929 saw the merger of the acquired railway business with those of Cammell Laird to form Metropolitan Cammell Carriage and Wagon (MCCW);