Initially as a possible replacement for the ever-present Douglas DC-3 the Convair CV-240 was an American airliner produced by Convair from 1947 to 1954. It brought a lot of new features that the DC-3 didn’t have, for example; a more modern design. The Convair 240 was able to make some inroads as a commercial airliner and also had a long development cycle which resulted in a number of civil and military variants.
Although being reduced in numbers by attrition, the “Convairliners” in its many forms continue to fly today, into the 21st century.
The design began life in a production requirement by American Airlines for an airliner to replace its Douglas DC-3s for many reasons.
Convair’s original design, the unpressurised Model 110 was a twin engine low wing monoplane of all metal construction, with seats for 30 passengers. The Convair CV-240 was powered by Pratt & Whitney R-2800 Wasp radial engines. It was also introduced with a tricycle landing gear, while the aircraft was fitted with a ventral airstair to aid passenger embarkation.
The Convair CV-240 first flew on July 8, 1946. But by the time, the American needs had changed the requirements to require pressurization deeming it to be too small. The first prototype was subsequently used by Convair for development work for the 240 series before being obsolete by 1947.
The Model 240 was followed into production by the Model 340 that had a longer fuselage, longer span wings and more powerful engines. The 340 first flew on October 5, 1951. In 1954, in an attempt to compete with turboprop-powered airliners like the Vickers Viscount, Convair produced the Model 440 Metropolitan, with more streamlined cowlings and new engine exhausts and improved soundproofing for the cabin. As the “Super 240” evolved into the CV-340 and CV-440 the limit of piston-engine performance was reached and the next developments centered on conversion to turboprop power.
The first delivery of a production Convairliner was to American on February 29, 1948. A total of 75 were delivered to American, with another 50 going to Western Airlines, Continental Airlines, Pan American Airways, KLM, Swissair, Sabena and Trans Australia Airlines.
Two Convair 580s of the Aspen, Colorado based Aspen Airways at Stapleton International Airport in Denver in 1986.
A CV-240 was the first private aircraft used in a United States presidential campaign. In 1960, John F. Kennedy used a CV-240 named Caroline (after his daughter) during his campaign. That aircraft is now preserved in the National Air and Space Museum.
After the aborted negotiations with TWA and Eastern for “Super 240” orders, the production of the 240 series was temporarily halted. In response to a United inquiry, however, Convair redesigned the Super 240, calling it the CV-340. United ordered 55, and more US orders came from Braniff, Continental, Delta, Northeast and National. Other orders came from abroad, and the CV-340 proved popular in South America. The CV-340 earned an enviable reputation for reliability and profitability, and was developed into the CV-440 Metropolitan, the final piston engined variant of the “Convairliners.”
Kelowna Flightcraft Air Charter, the major remaining operator of this model, currently holds the type certificate for this aircraft. Used price for a Convair 240 in 1960 was around £40,000…