Propliner

A propliner is a large, propeller-driven airliner. Typically, the term is used for piston-powered airliners that flew before the beginning of the jet age, not for modern turbine-powered propeller airliners. With the notable exception of the de Havilland Albatross (1937), which was largely fabricated of wood, propliners featured all-metal wings and structural members, retractable landing gear, and generally two or four engines.

The first propliner was the Boeing 247 (1933), with the Douglas DC-1 and DC-2 closely following. The most successful is the Douglas DC-3, which was produced in the thousands, and is still in widespread use. Other American-designed propliners included the Douglas DC-4, DC-5 and Martin 2-0-2s. None of these models featured cabin pressurization, although it was offered as an option upon the Douglas DC-4.

With the earlier introduction of the Stratoliner, a second generation of Propliners ensued. These technologically more modern aircraft featured cabin pressurization systems allowing greater comfort by allowing aircraft to fly higher and above much of the lower altitude weather. Although it was not until the Lockheed Constellation, followed by the DC-6 and DC-7 were introduced for this design advance to become common.

By the 1950s the traveling public were increasingly finding themselves being transported upon long range pressurized propliners with aerial names like the; , Lockheed Super Constellation, or Starliner, or shorter ranged twin engined; 4-0-4s, and Convair CV-240, CV-340, and CV-440 aircraft.

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