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
Regional airliner and British Aerospace ended production of their BAe Jetstream 41 after 100 delivered. By 2006 only the ATR 42/72 models and the Dash 8 remained in production. Turboprop airliner deliveries are correlated with oil prices with a lag of a few years. Another reason for the downturn in the turboprop market was the introduction of the first regional jets. Although a number of small jets entered service in the 1950s and 60s, notably the Sud Aviation Caravelle, Fokker F28 Fellowship and DC-9, these could not compete in terms of cost of operation with the turboprop designs, and were suitable for